ML19323A875
ML19323A875 | |
Person / Time | |
---|---|
Site: | Pilgrim, 05000471, 05000472 |
Issue date: | 04/30/1980 |
From: | Richard Anderson, Mogolesko F, Scotton L BOSTON EDISON CO. |
To: | |
Shared Package | |
ML19323A869 | List: |
References | |
NUDOCS 8005060160 | |
Download: ML19323A875 (200) | |
Text
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- g Re!cted to Cperation cfAtyimlictica l SEMI-ANNUAL REPORT NUMBER 15 JANUARY 1979 - DECEMBER 1979 l
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BOSTON EDISON COMP NY ' NUCLEAR ENGINEERING DEPARTMENT l ENVIRONMENTAL SCIENCES GROUP E F6d MUMsi
s ~ ~ MARINE ECOLOGY STUDIES RELATED TO OPERATION OF PILGRIM STATION E E ~ SEMI-ANNUAL REPORT NO.15 P REPORT PERIOD: JANUARY 1979 THROUGH DECEMBER 1979 L DATE OF ISSUE: APRIL 30,1980 Compiled and Reviewed by: 'b Robert D. Anderson Senior Marine Fisheries Biologist [ ' tl 21 Lewis N. Scottod ~ { Senior Marine Fisheries Biologist Approved by: /U' 4 . 2 Dr. Fred J.MogolesKo [ Environmental Sciences Gruup Leader [ Nuclear Engineering Department [ Boston Edison Company 800 Boylston Street Boston, Massachusetts 02199 [ [ [
I TABLE OF CONTENTS SECTION I Summary II Introduction III Marine Biota Studies IIIA Marine Fisheries Studies Progress Report on Studies to Evaluate Possible Effects of the Pilgrim Nuclear Power Station on the Marine Environ-ment, Project Report No. 28 (July - December 1979) (Mass. Dept. of Fisheries, Wildlife and Recreational Vehicles; Divi-sion of Marine Fisheries) IIIB Benthic Studies Benthic Studies in the Vicinity of Pilgrim Station, September
- December 1979 (Taxon, Inc.)
IIIC Plankton Studies IIIC.1 Progress Report on Investigations of Entrainment of Ichthyoplankton at Pilgrim, January - December 1979 (Marine Research, Inc.) IIIC. 2 Investigations of Larval Winter Flounder in the Plymouth Harbor - Duxbury Bay Estuary, Spring 1979 (Marine Research, Inc.) IIID Impingement Studies I Impingement of Organisms at Pilgrim Nuclear Power Station: January - December 1979. (Boston Edison Company) IV Fish Surveillance 3tudies ! IVA Overflights Summary Report: Fish Spotting Overflights in Western Cape Cod Bay in 1979. (Boston Edison Company) IVB Barrier Net Summary Report: 1978-1979 Inspections of Pilgrim Dis-charge Canal end Fish Barrier Net. (Boston Edison Company) I V Find Report on Reproduction and Spawning Population Struc-ture of Anadromcus Rainbow Smelt, Osmerus mordax (Mitchell), in the Jones River, Massachusetts. February 1980 (Mass. Dept. of Fisheries, Wildlife and Recreational Vehicles; Division of I Marine Fisheries) VI Minutes of Meetings 44 and 45 of the Administrative-Technical l Committee, Pilgrim Nuclear Power Station l 8
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I
SUMMARY
I Highlights of the environmental surveillance and study program results obtained over this reporting period (January - December 1979) are presented below: I Marine Fisheries Studies:
- 1. Irish moss landing statistics for 1979 compared to 1978 in-dicate that landings declined 3.9%, effort declined 1.9% and harvest rate declined 2.i t. Harvest rate from Area 5 (Pil-grim Station - 186.9 lbs/hr) increased 26.4% from 1978, but Area 1 (control) harvest rate (225.3 lbs/hr) decreased 1.2%
below the 1978 rate. This indicates Pilgrim Station opera-tion had no adverse impact on the Irish moss species.
- 2. Winter flounder, skate spp. , yellowtail flounder, ocean pout, windowpane and longhorn sculpin accounted for 96.5% of the January - December 1979 benthic fish catch. Mean catch l
per unit of effort (CPUE) for all species increased substan- ! tially in 1979 compared to 1978, from 27.0 to 73.2. CPUE increased from 1978 for winter flounder (10.6 to 32.0), yellowtail flounder (4.1 to 11.6), skate spp. (5.4 to 14.4), windowpane (2.5 to 7.7), ocean pout (0.9 to 2.2) and long-horn sculpin (1.1 to 3.2). Pelagic fish mean catch (232.5 l fishes / set) increased from 1978 when 202.0 fishes / set were taken. Pollock (37.4%), Atlantic herring (24.1%) and cunner (16.6%) accounted for 78.1% of the total catch. Pollock I-1
l 1 CPUE decreased from 91.3 to 86.9, Atlantic herring in- i creased 22.3 to 56.0 and cunner declined 44.0 to 38.6 compared to January - December 1978. It was concluded
)
that Pilgrim Station operation had no detrimental effect i on benthic and pelagic fish studied in 1979. l
- 3. Adult lobster mean monthly catch rate per pot haul in May - -
November 1979 was 0.47 lobsters. In the Pilgrim Station ; immediate discharge area the legal lobster catch rate (0.44) was comparable to the average of all other areas com-bined (0.48). Overall catch rate (legals plus sublegals) I was 2.2 for the discharge area and slightly less (2.0) for all other areas. I
- 4. In April - October 1979 fish observational dive surveys seven species were observed in the thermal plume area. I Cunner and pollock were among the most numerous species seen. Other than 2 lethargic winter flounder and I lethargic tautog in the thermal plume in April and September respectively, no other fish showed abnormal behavior and no gas bubble disease symptoms were observed. Most spe- I cies were in greatest concentrations at stations in the di-rect path of the thermal plume, indicating attraction to the Pilgrim Station thermal effluent.
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- 5. The dissoived nitrogen gas saturation values for the dis-charge effluent exceeded 115% approximately 59.0% of the I-2
I I. time in March - November 1979. Mean nitrogen saturation values were generally 100-105% at the intake and increased I in the discharge with a mear high of 119% in March. Mean monthly nitrogen gas saturation levels in the discharge canal exceeded 115% during most months although no mor-talities due to gas bubble disease were recorded. I 6. During two backwash operations at Pilgrim Station, on 3 May and 28 August, 4 dead cunner and 4 dead crabs were recorded in the intake embayment, respectively. They may potentially have died from the sudden rise in, temperature associated with backwashes. In July, 75 dead short-finned squid and a number of mutilated silversides were noted in the intake embayment not associated with any backwashes, and they possibly died as a result of natural predation. I Impingement Studies:
- 1. The mean January - December 1979 impingement collection rate was 3.24 fish /hr. The rate ranged from 0.14 fish /hr (July) to 9.79 fish /hr (April) with Atlantic silverside com-prising 73.3% of the catch, followed by rainbow smelt at 5.4% and windowpane at 2.9%.
I
- 2. March and April Atlantic silverside impingement accounted for 71.1% of all fishes sampled from January - December 1979. This high impingement of Atlantic silversides was I I-3 lI L
the ninth largest fish mortality incident in Pilgrim Station operational history, but most likely insignificant to this species prolific population levels. I
- 3. The mean 1979 invertebrate collection rate was 18.44/hr with the blue mussel accounting for 92.2% and sand shrimp 2.3% I of the catch.
- 4. Two American lobsters were sampled for a rate of 36 lobsters / year assuming 100% operation of Pilgrim Station.
Fish Surveillance Studies:
- 1. Fish overflights in 1979 spotted five major species categories:
herring. Atlantic menhaden, pollock, Atlantic mackerel and baitfish. Herring (probably alewife and/or blueback herring) and pollock were observed (several thousands of pounds) within the Pilgrim intake embayment in July and May, re-spectively. Also, tens of thousands of pounds of Atlantic menhaden were noted within a few hundred yards of the discharge canal from late-July through early-September. However, no incidents occurred involving these species.
- 2. Dive inspections of the fish barrier net at the end of the I
l Pilgrim discharge canal revealed it was operating success-l l fully in excluding fishes during 1978 and 1979. Several species of biota that were resident in the discharge canal, 1 or could pass the barrier net's 2" mesh were noted I-4
'I I upstre.am of it. No live individuals observed appeared stressed or showed gas bubble disease symptoms. Many herring and sportfish were in evidence downstream (seaward) of the barrier net as indicated by sportfishermens' catches and a herring kill in August 1978. j Smelt Reproduction:
- 1. Rainbow smelt spawning activity in the Jones River in 1979 commenced on 22 March at a water temperature of 45 F and terminated on 28 April at a water temperature of 59 F.
Spawning activity was only apparent at night and 12,597 l smelt were collected with a sex ratio of 8.86 males to 1.00 ; females. I 2. Predominant among the five age classes of smelt collected were two-year old fish, accounting for 64.8% of the total run.
- 3. Mean egg density for the 1979 smelt spawning run in the Jones River was 51,808.32 eggs /ft2 which is over 100 times greater than the optimum egg density (487/ft2 ) reported in the literature for maximum egg survival.
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- 4. Total smelt egg production for 1979 in the Jones River was 4.7 x 10 which compares favorably and is well within an order of magnitude of the value used in the Pilgrim Station 316 Demonstration (1977) smelt model.
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- 5. Pathological examination of smelt revealed that 16.5% and 97.1% were infected by Glugea and piscine erythrocytic necrosis (PEN), respectively. These infections have been reported to at least weaken and debilitate fishes.
Benthic Studies:
- 1. Faunal community composition indicated there was no major difference between the effluent site and controls.
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- 2. Faunal studies indicate thermal addition may be responsible for the slightly abnormal faunal community structure at the effluent 10' rock site.
- 3. Thermal loading appears to be influencing densities of three faunal species in the effluent area.
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- 4. Algal studies showed that Chondrus and total algal biomass values fluctuated more widely at the effluent than at the two control stations.
Plankton Studies:
- 1. Entrainment
- a. A total of 37 species of fish eggs and/or larvae were found in the 1979 entramment collections.
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- b. Egg collections for 1979 were dominated by Atlantic cod (January - March, November - December), American plaice (April), labridae - Limanda group (May - August), j tautog and cunner (April - August), windowpane, rockling and hake (late August - October).
I
- c. Larval collections for 1979 were dominated by rock
,I gunnel (January - April), sand lance (January - April and December), winter flounder (April - May), grubby (January - April), and cunner (June - August), rockling, windowpane, menhaden and tautog (September), rockling, silver hake, hake and window-pane (October), and Atlantic herring (November). 1
- d. One lobster larva was collected in the entramment samples for 1979.
I 1
- 2. Winter Flounder Larvae I a. Ichthyoplankton tows for larval winter flounder (Pseudopleuronectes americanus) at eight stations in Plymouth Harbor - Duxbury Bay (PHDB) yielded lower abundance in 1979 than in 1978.
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- b. By the end of the sampling period (May 31 - June 1) it was evident that flounder larvae abundance estimates for the four years, 1976 - 1979, were essentially indistinguishable.
- c. Entramment at PNPS was generally very low in the 1979 samples. Entramment rates appear to bear little relation to PHDB stocks over the 1976 - 1979 period.
I
- d. Adult winter flounder catch per tow near PHDB sug-gests a decline in flounder populations from 1970 -
1975 and increasing abundance from 1976 - 1979. I I I I ! I I I I I I-8
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1 1 I INTRODUCTION I j i 1 A. Scope and Objective This is the fifteenth semi-annual report on the status and results l of the environmental surveillance and study programs related to the operation of Pilgrim Nuclear Power Station (PNPS). The study programs discussed in this report relate specifically to the Cape Cod Bay ecosystem with particular emphasis on the Rocky l Point area. This is the third semi-annual report in accordance with the environmental monitoring and reporting requirements of the PNPS Unit 1 (#MA0003557) and Unit 2 (#MA0025135) NPDES permits from the U.S. Environmental Protection Agency. I multi-year (1969-1977) report incorporating marine fisheries, A l 1 1 benthic, plankton-entramment and impingement studies was sub- ' mitted to the NRC in July 1978 as required by the PNPS Ap-pendix B, Tech. Specs. Programs in these areas have been continued under the PNPS NPDES permits. I . The objectives of the Environmental Surveillance and Study Pro-gram are to determine whether the operation of PNPS results in measurable effects on the marine ecology and to evaluate the sig-nificance of any observed effects. If an effect of significance is detected, Boston Edison Company has committed to take steps to correct or mitigate any adverse situation. These studies are guided by an Administrative-Technical Committee which is chaired by a member of the Massachusetts Division of Marine Fisheries .I II-1
I and whose membership includes representatives from the Univer-sity of Massachusetts, the Mass. Division of Water Pollution Con-trol, the National Marine Fisheries Service, the U.S. Bureau of Sport Fisheries and Wildlife, the U.S. Environmental Protection Agency and Boston Edison Company. Copies of the Minutes of the Pilgrim Station Administrative-Technical Committee meetings held during this reporting period are included in Section VI. B. Marine Biota Studies
- 1. Marine Fisheries Studies A marine fisheries study initiated in 1969 is being conducted I by the Commonwealth of Massachusetts, Division of Marine Fisheries (DMF).
I In the marine fisheries study, submersible thermographs were employed to obtain near-continuous temperature re-cords off the site. A hydrographic buoy (location shown in Figure 1) was established at a distance of approximately one-half mile offshore from Pilgrim Station in June,1970 as part of the pre-operational surveillance program and was maintained during the post-operational studies to provide direct comparisons of water temperature before and after plant operation. Temperature records were obtained from three depths in the water column. This program was dis-continued in 1979 as its NRC Tech. Spec. requirements r had axpired, and a substantial body of data had been accumulated. l II-2
1 1 I The occurrence and distribution of fish around Rocky Point and at sites outside the area of predicted temperature increase are being studied. Groundfish and pelagic species
, are sampled using trawl and gill net collections (Figure 1) made at approximately two-week intervals. In 1979, 2 ad-ditiual trawl stations were added to the existing 3 stations with less . "
sampling. I Studies have been conductei since early 1970 of local lob-ster stock catch statistics for areas off Rocky and Manomet Points . Catch statistics (Figure 2) continue to be collected approximately weekly throughout the fishing seasori. I The recording of total landings of Irish moss harvested in the study area began in 1971. To facilitate comparisons of the amount of moss harvested in the immediate discharge area with control areas, the coastline was divided into eight monitoring zones (Figure 3). The total weight of moss harvested end the effort expended within each monitoring zcae by each raker is recorded daily. I ,g Since March 1975 Pilgrim intake and discharge waters have
- g been analyzed every week for dissolved gases. In 1979, weekly gas monitoring was initiated only in Spring through Fall seasons. A Weiss saturometer is used in situ, to meas-ure total partial pressure of dissolved gases, and percent saturation of nitrogen, oxygen and total gas are determined.
1 l l ] II-3 I
I A finfish observational dive program was initiated in June 1978. SCUBA gear is utilized on biweekly dives from April-October in the PNPS thermal plume area. I Results of the marine fisheries studies during the reporting period are presented in Section IIIA.
- 2. Benthic Studies I
The studies described in this report were conducted by Taxon, Inc. , Salem, Massachusetts. l The benthic flora and fauna were sampled along three transects extending perpendicular to the shoreline at depths ranging from the intertidal to 20 feet (MLW) (Fig-ure 1). Quantitative (sand and rock substrata) and qual-itative (rock substratum) samples were collected, and the dominant 'lora and fauna in each plot were recorded. Sampling was conducted four times per year to determine biotic changes, if any. Results of the benthic surveys reported during this period are discussed in Section IIIB. l , 5
- 3. Plankton Studies Since August 1973, Marine Research, Inc. (MRI) of Falmouth, Massachusetts has been studying entrainment in Pilgrim Sta-I tion cooling water of fish eggs and larvae, and lobster lar-vae (from 1973-1975 phytoplankton and zooplankton were also studied). Since 1976, MRI has studied abundance of II-4
I winter flounder larvae in PHDB (Figure 4). Information generated through these studies has been utilized to make l periodic modifications in the sampling program to more ef-ficiently address the question of the potential effect of entrainment. These modifications have been developed by ) the contractor, and reviewed and approved by the Pilgrim 1 A-T Committee on the basis of the program results. I Plankton studies in 1979 emphasized consideration of ; i ichthyoplankton entrainment, as well as distribution and abundance of winter flounder larvae. Results of the ichthyoplankton entrainment and winter flounder larvae studies for this reporting period are dis-cussed in Sections IIIC.1 and IIIC.2, respectively.
- 4. Impingement Studiac The Pilgrim 1 impingement program commenced in November I 1972 to speciate and quantify the organisms carried onto i
the four intake traveling screens. Through June 1976 the Mass. Division of Marine Fisheries reported on collections by private contractors. In January 1977 Marine Research Institute began both collecting and reporting on results of this program. Since January 1979, Marine Research, Inc. , has been conducting impingement sampling with results being reported on by Boston Edison Company. lI lI II-5
I Results of the impingement program for this reporting pe-riod are discussed in Section IIID. 3 C. Fish Surveillance Studies 5 In Spring 1976 regular fish spotting overflighn were commenced as part of a continuing effort to monitor the times when large concentrations of fish might be expected in the Pilgrim vicinity. Since September 1976, and regularly from May-October since 1978, dive inspections have been conducted of the Pilgrim dis-charge canal in order to evaluate fish barrier net durability, and effectiveness in excluding fishes from the discharge canal. I Summary reports for these efforts for 1979 are presented in Sections IVA and IVB respectively. I D. Smelt Reproduction As a result of the impingement mortality of approximately 6,200 rainbow smelt in December 1978, a smelt reproduction and spawn-ing study was conducted in Spring 1979. A final report for 1979 is included in Section V. E. Station Operation History The daily average reactor th;rmal power levels from July through December 1979 are shown in Figure 5, and for July 1972 - December 1979 in Figure 6. I I ( II-6
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L . e L PROGRESS REPORT OtC:' STUDIES TO EVALUATE POSSIBLE EFFECTS [ OF THE PILGRIM NUCLEAR POWER STATION ON THE MARINE ENVIRONMENT r L [
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E Project Report No. 28 (July-December, 1979) Summary Report No. 9 E [ [ by Robert P. Lawton, Phillips Brady, ( Christine Sheehan, and Mando Borgatti [ [ [ February 29, 1980 Massachusetts Department of Fisheries { Wildlife and Recreational Vehicles Division of Marine Fisheries 100 Cambridge Street Boston, Massachusetts 02202 { [ [
TABLE OF CONTENTS n I L L^11 [ L_ INTRODUCTION 1 LOBSTER CATCH 2 IRISH MOSS HARVEST 7
, OTTER TRAWL 13 r-GILL NET 41 UNDERWATER FINFISH OBSERVATIONS 54 GAS SATURATIONS 63
{
SUMMARY
73 ACKNOWLEDGEMENTS 76 _ LITERATURE CITED 77 APPENDIX A-1 m [ i
I LIST OF TABLES Table Page
- 1. Total yaarly lobster pot catch, 1970-1979. 4
- 2. Average legal lobster catch "er pot haul per 5 5 month for all quadrates combined.
- 3. Irish moss landing statistics frca 9 the vicinity of PNPS, 1971-1979.
4 Check list of finfish species (following classification of American 16 Fisheries Society, 1970) collected er observed in the adjacent waters l
=
of Pilgrim Station, January - December, 1979. Sa. Trawl catch data at stations 1-3, 1979 18 Important commercial species Winter flounder (Pseudocleuronectes americanus) 5b. Trawl catch data at stations 4 and 5, 1973 21 Important commercial species Winter flounder (Pseudopleuronectes americanus)
- 6. Mean annual catch per 20 minute tow for winter 23 flounder at stations sampled in the adjacent g waters of PNPS. g
- 7. Trawl catch data, 1979 25 Dominant community species Station 1 (Warren Cove)
- 8. Trawl catch data, 1979 27 Pominant community species Station 2 (30' Contour)
- 9. Trawl catch data, 1979 29 l Ccminant community species 5 Station 3 (40' Contour)
- 10. Trawl catch data, 1979 31 i Dominant community species Station 4 (Rocky Point)
- 11. Trawl catch data, 1979 32 Dcminant community species Station 5 (White Horse)
- 12. Mean annual catch per 20 minute tcw for skate spp, at statiens sampled in the adjacent wa- E ters of PNPS. g l 11
LIST OF TABLES (cont.) E Table Page 13a. Trawl catch data at stations 1-3, 1979 34 { Important commercial species Yellowtail flounder (Limanda ferruginea) [ 13b. Trawl catch data at stations 4 and 5, 1979 Important commercial species 37
, Yellowtail flounder (Limanda ferruginea) 14 Mean annual catch per 20 minute tow for yellow- 39 tail flounder at stations sampled in the adja-cent waters of PNPS.
- 15. Mean annual catch per 20 minute tow for window- 40
{ pane at stations sampled in the adjacent waters of PNPS.
- 16. Mean annual catch per 20 minute tow for long- 42 horn sculpin at stations sampled in the adja-cent waters of PNPS.
- 17. Mean annual catch per 20 minute tow for ocean 43 peut at stations sampled in;the adjacent wa-ters of PNPS.
( 18. Numerical rank, number, and percent composition of finfish taken in the vicinity of PNPS by gill 45 net (five panels of 3.8 - 8.9 cm mesh) in 1979.
- 19. Gill net collections, 1979 48 Selected species ;
Rocky Point, Plymouth j
- 20. Mean annual catch per standard gill net (five panels of 3.8 - 52 8.9 cm mesh) set (CPUE) for selected species collected in the vicinity of PNPS, 1971 - 1979.
{
- 21. Occurrence of finfish species at 56 each observational station from 24 April through 17 Octobers 1979.
- 22. Approximate numbers of finfish species that occurred 57 at each observational station from 24 April through
(. 17 October, 1979. (
-111 ~
t LIST OF TABLES (cont.) i f Table Page , l
- 23. Dissolved gas analyses at PNPS, March-November, 1979. 64 24 Percent distribution of saturation levels of 71 total dissolved gas, nitrogen plus argon, and
, oxygen at PNPS, March-November, 1979. l \ I I I l I l I 8 I I I I I iv
u LIST OF FIGURES S Figure g
- 1. Distribution of lobster 3 pots sampled in 1979.
- 2. Irish moss harvest areas. 8'
- 3. Annual mean harvest rates for area 1 (---), 11 area 5 ( -), and pooled area data ( ),
1971 - 1979. 4 Benthic fish trawl station . 14 locations in Pilgrim vicinity. ~
- 5. Gill net station location 44 Rocky Point, Plymouth.
- 6. Finfish observational diving 55 stations at PNPS.
- 7. Monthly ranges and mean saturation values of total 67 dissolved gas (Stot), PNPS, March-November, 1979.
- 8. Monthly ranges and mean saturation values of dissolved 68 nitrogen plus argon (SN +Ar), PNPS, March-November, 1979.
- 9. Monthly ranges and mean saturation values of dissolved 69 oxygen (SO ), PNPS, March-November, 1979.
2 [ [ b [ [ - V
INTRODUCTION This report summarizes data collected January-December, 1979 by the Division of Marine Fisheries (DMF) in the environs of Pilgrim Nuclear Power Station (PNPS). Studies are conducted to detect and evaluate non-radiological impact of PNPS-Unit I operation on marine resources in off-site waters of Cape Cod Bay. Numerical tabulations, plots and computed indices of abundance are compared spatially and temporally to identify basic data trends and rela-tionships. Unless indicated, sampling methods and materials are consistent with prior investigations. J L 4 0 1
I LOBSTER CATCH During 1979, 2,820 1.obster pots were sampled, bringing the study total to 31,007. Data were obtained for 5,596 lobsters of which 1,325 were of legal I size (> 81 mm carapace length). Distribution of total pots sampled by area is shown in Figure 1. A summary of catch data by quadrat is included as an appendix to this report. Due to a delay in lobster pot deployment and changes in project personnel, sampling was not initiated until 31 May and was reduced in effort during September and October. However, total sample size (i.e. number of pots and lobsters sampled) was consistent with past postoperational years (Table 1). Care was taken to minimize sampling bias by utilizing established landmarks to determine quadrat location. Mean monthly catch rates of legal lobsters (pooled spatial data), for 1970-1979, are presented in Table 2. Monthly rates, reflecting past seasonal trends, declined during ecdysis and increased with heightened lobster activity following the molt. Seasonal (May-November) mean catch per pot haul (catch rate) of legal lobsters was 0.47, the second lowest value obtained since sampling commenced. Overall catch rate (pooled legal and sublegal data) was 2.0 - the lowest level for the entire study (Table 1). . However, this reduction in catch rate, which infers declining lobster catch and/or increased harvesting pressure, may be an artifact of sampling. Of the total pots sampled in 1979,28.0's were examined in May-June, when legal catch rates were at their lowest, whereas in September and October, the number of pots sampled comprised only 16.7% of the study total. The level of samp-ling in these latter months was 40.2% lower than that for May and June. When compared to mean values (0.81 - September, 0.79 - October) for all previous I I 2
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[ Figure 1. Distribution of lobster pots sampled in 1979. [ . [A total of 16 pots in quadrats T-ll(8) and S-10(8) were sampled [ further south and east.] 3
Table 1. Total yearly lobster pot catch, 1970-1979. Overall Overall No. of Total Sub- Catch Legals Year Pots Catch Male remale Legals legals Eggers Per Pot Per Pot 1970 3200 11399 4950 6449 1889 9334 195 3.6 0.59 (43) (51) (17) (82) (2) 1971 4376 15158 6543 8615 2855 12043 260 3.5 0.65 (43) (57) (19) (79) (2) 1972 3449 12f n 5484 7051 2522 9849 166 3.6 0.73 (44) (56) (20) (79) (1) 1973 2762 7821 3456 4363 1490 6267 68 2.8 0.54 (44) (56) (19) (80) (1) 1974 2762 8386 3838 4558 1922 6426 41 3.0 0.70 (46) (54) (23) (77) (0.5) 1975 2762 8210 3757 4443 1306 6884 20 3.0 0.47 (46) (54) (16) (84) (0.2) 1976 2959 9179 4308 4871 1352 7819 8 3.1 0.46 (47) (53) (15) (85) (0.1) 1977 3485 7694 3646 4078 2050 5596 27 2.2 0.59 (47) (53) (27) (73) (0.4) 1978 2432 7717 3432 4285 1535 6147 35 3.2 0.63 (44) (56) (20) (80) (0.5) 1979 2820 5596 2339 3257 1325 4214 57 2.0 0.47 (42) (58) (24) (75) (1) (Percent of total catch is shown in parenthesis) m M M M W M M M M W W W W _ M W W W M gj
I Table 2. Average legal lobster catch per pot haul per month for all quadrates combined. 8 March April May June July Aug Sept Oct Nov 1970 - - 0.41 0.30 0.54 0.75 0.61 0.68 0.80 (330) (351) (627) (667) (571) (691) ( 72) 1971 0.68 0.46 0.62 0.32 0.68 0.86 0.77 0.70 - ( 95) (331) (681) (591) (723) (730) (668) (668) I 1972 - 0.59 (428) 0.55 (248) 0.31 (519) 0.66 (718) 0.80 (707) 1.30 (477) 0.88 (352) 0.41 0.74 0.56 0.82 I 0.46 1973 - 0.39 0.60 - (135) (646) (634) (625) (295) (279) (151) 1974 - - 0.38 0.33 1.00 0.51 1.09 0.64 - (309) (341) (544) (595) (499) (455) 1975 - 0.32 0.23 0.26 0.64 0.58 0.81 0.70 0.65 (322) (525) (555) (314) (299) (278) (269) (233) 1976 - - 0.27 0.21 0.69 0.59 0.34 1.11 0.63 (438) (541) (641) (554) (570) ( 37) ( 17 8 ) 1977 - 0.48 0.46 0.29 0.55 0.47 0.72 0.86 - (379) (417 ) (203) (555) (663) (604) (664) 1978 - - 0.41 0.30 0.63 0.62 1.09 0.71 (374) (571) (441) (775) (279); (162) 1979 - - 0.31 0.29 0.54 0.59 0.50 0.42 0.58 (130) '359) (797) (491) (200) (272) (271) (number of pots hauled) i I I
- I 1
1
I years, monthly legal catch rates for September and October, 1979, were sub-stantially reduced (Table 2). Decreased sampling during these months may have biased catch rate data and resultant catch rate calculations thus depressing the final yearly figure. Monitoring lobster catch was undertaken to assess long-term impact of PNPS operation on the local lobster population and fishery. Natural variability, seasonal fluctuations in lobster activity and unequal sample size of pots by quadrat contribute to a "casking" effect when assessing population changes. In contrast with former years, one of the participating lobstermen concentrated more of his fishing effort in quadrats south of Manomet Point. A total of 1,234 pots representing 43.8% of the annual total, was located in this southern region, i.e. quadrats N, 0, P, Q, R, S and T (Figure 1). This contrasts with the 263 pots in 1977 cnd 460 pots in 1978 sampled from this region. The effect of this spatial shift in fishing concentration was not determined. However, legal catch rate (pooled 1979 data) for this southern region was 0.48, which is similar to that (0.50) of the northern quadrats, D through M (Table 1). Catch rate of legal lobsters from the discharge area (quadrats I-12, I-11, H-11 and H-12) was 0.44 as compared to 0.48 for all other quadrats com-bined. Total catch rate (including legal and sublegals) forthis surveillance area was 2.2, which is slightly higher than the 2.0 for all other areas ccabined (Appendix). A total of 57 ovigerous females was sampled (Table 1). These individuals represented 1.0% of total catch and 1.8% of all captured females. The former value (1.0%) is the highest obtained since 1973. Lobsters in Cape Cod Bay require a minimum of five years to reach har-vestable size (Mass. Division of Marine Fisheries 1973). The stock, currently I l I 6
I being exploited in the vicinity of FNPS, consists in part of individuals hatched the year PNPS began co :mercial operation. As a result of extended plant outages during postoperational studies, a possible lag phencmenon may affect the reaction time of local lobsters to possible plant effects. This, in effect, may extend the time interval required for detection of possible population alterations due to impact of PNPS operation. Decline in the total and legal catch rates in 1979 may reflect a decreasing population and/or expanded commercial fishing effort. Continued examination of pot catch data for possible trends will aid in determination of population 5 alterations. I IRISH MCSS HARVEST Tor the ninth consecutive year, landings of Irish moss (Chondrus crispus) were recorded in an ongoing effort to examine impact of PNPS on this resource. Harvesting of Irish moss commenced this year on 6 June and terminated on 3 September. Harvest areas are depicted in Figure 2. Landing statistics for 1971-1979 are summarized in Table 3. Figure 3 compares annual harvest rates for Areas 1 (reference) and 5 (surveillance) and for pooled data from 1971-1979. During 1979, rakers expended 1,337.7 hrs and harvested 227,293 lbs (wet weight) of moss at a mean rate of 169.9 lbs/hr from the study area. Totals exclude 12,765 lbs collected from the Ellisville area and landed at White Horse Beach and 3,085 lbs raked from the study area on 29 July for which effort records are lacking. Adverse weather conditions prevented raking on 27 days during the harvesting season. A total of 425 boat trips was made in 64 work-days involving 1-18 craft per day. Pooled area data indicated a slight decline in harvesting parameters frem I I 7
ee I B E llI
-. a. - . s ~ o e.r . . . .._.g. .
0 1/2 1 N L=-%~ = - a SCALE IN MILES , loy Brach - PL YMOUTH MARBOM .
\ /
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/ g ~\ s -
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,e L g*w N 4.,,,,, c .. ,.
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_- [ Pomt l Figure 2. Irish moss harvest areas, I l O l l l l l I l
i n J 1 O W FM MM M M M 'NW R f L.__]R F Table 3. Irish moss landing statistics from the vicinity of PflPS, 1971-1979. Landings (1bs-wet weight) Area 1971 1972 1973 1974 1975 1976 1977 1978 19794 1 92,637 133,402 57,045 105,110 79,652 72,950 68,045 54,685 56,240 l 2 78,060 110,246 45,310 91,290 89,614 125,140 129,235 110,668 76,297 3 10,719 17,295 4,140 11,730 16,487 25,250 16,680 12,824 12,830 4 23,252 31,402 7,695 10,795 14,317 7,010 16,275 9,864 13,037 5 82,724 78,567 18,815 28,515 72,557 56,330 65,595 34,870 37,582 6 39,925 56,881 24,995 17,230 74,417 24,280 29,145 10,580 31,237 7 14,727 17,004 30 215 10,517 2,230 - 2,215 70 8 33,429 28,368 605 25 3,252 235 1,025 660 - 375,473 473,165 158,635 264,910 360,813 313,515 326,000 236,366 227,293
- Does not include 3,0851bs from study area for which effort was not recorded. .
/
I. Table 3. Irish moss landing statistics frem (cent.) the vicinity of PNPS, 1971-1979. Effort (hours) Area 1971 1972 1973 1974 1975 1976 1977 1978 1979 1 411.4 573.1 343.4 446.4 339.2 373.3 291.8 239.8 249.6 e' 2 44').7 776.3 345.8 391.9 562.8 840.3 959.2 721.5 551.7 ' 3 55.7 90.6 22.8 77.8 83.0 149.6 145.3 56.0 102.2 4 113.6 155.9 41.3 39.7 47.9 47.8 100.0 59.1 99.0 5 406.8 374.9 102.3 139.7 290.7 284.2 322.5 236.0 201.1 6 170.7 233.9 128.8 79.0 219.5 88.7 137.5 42.5 133.6 7 87.6 80.3 0.1 1.3 27.8 11.2 - 5.8 0.5 " 8 119.7 108.1 1.4 0.3 13.9 1.2 3.3 2.8 - 1809.2 2393.1 985.9 1176.1 1584.8 1796.8 1959.6 1363.5 1337.7 Harvest Rate l (1bs/hr) 5 Area 1971 1972 1973 1974 1975 1976 1977 1978 1979 1 225.2 232.8 166.1 235.5 234.8 195.4 234.4 228.0 225.3 2 175.9 142.0 131.0 232.9 159.2 148.8 134.7 153.4 138.3 3 192.4 190.9 181.6 150.8 198.6 158.8 114.8 229.0 125.5 4 204.7 201.4 186.3 271.9 298.9 146.8 162.8 166.9 131.7 5 203.4 209.6 183.9 204.1 249.6 198.2 203.4 147.8 186.9 6 233.9 243.2 193.7 218.1 339.0 273.8 212.0 248.9 233.8 7 168.1 211.8 300.0 165.4 378.3 207.8 - 381.9 140.0 8 79.3 262.4 432.1 83.3 234.0 201.5 307.5 235.7 - R* 207.5 197.7 160.9 225.2 227.7 174.5 166.4 173.4 169.9
- R = mean harvest rate 10
M M M M M M M M M M M - E R fl FMR TR i figure 3. Annual mean harvest rates for area 1 (---),
- area 5 ( - ), and pooled area data ( ),
1971 - 1979. 250-
" ~ . -\ /
s~~~-*n-s . - s .
,es _ ' ~ . . - -- AREA1 N \
s ,.- N*. '
,' (control) s -
- r. ,
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200-
.'s 3, / / 's,/ (........ \* . .# * .. AREA 5 g ...*/
s / . .- (surveillance) ss '/ liarvest Rate
.. ^ Pooled area . ,.- data (lbs/hr) 150- .*
U 100-l 50- . l l I 5 3 3 3 3 I I 1971 .1972 1973 1974 1975 1976 1977 1978 1979 Years
I that of 1978: total landings (3.9%), total effort (1.9%), and mean harvest rate (2.0%). Percent distributions of landings by month were: June (34.8%), July I (47.5%), August (16.2%), and September (1.4%). Landings are influenced by harvesting effort. Decline in effort through August into early September was similar to findings for 1977 and 1978. As the harvesting season progressed, cropping of moss decreased stock availability which dampened raker enthusiasm. It was noted at the commencement of this harvesting season that a species of brown alga (Laminaria spp. ) inhabited tracts of bottom previously dominated by Irish moss. The effect of this possible replacement phenomenon on landings was undetermined. For the fifth consecutive year, highest annual landings and greatest effort were recorded from Area 2, the landing site (White Horse Beach). How-ever, harvest rate there averaged only 138.3 lb/hr, which was fifth in effi-ciency for all areas. Apparently, this reflects extensive harvesting pressure at this location. Effort was 2.2 times greater than in Area 1 (reference) and 2.7 times greater than in Area 5 (surveillance). Second highest landings and harvest rate occurred in Area.1. Area 5 was third in both landings and harvest rate. A comparison with 1978 data revealed that in 1979, harvest rate declined 1.2% in Area 1 but increased 26.4% in Area 5. Harvest rate in Areas 1 and 5 comprised 98.4% and 90.5% of respective preoperational averages. Although harvest rates approached pre-operational levels, landings decreased by approximately 50%. Effort for both areas however, had decreased by 49.3% and 65.8%, respectively, from preoper-ational levels. Similarity in harvest rates both spatially and temporally suggests com-i 12
I I parable moss densities but does not necessarily imply parity in total production. Factors which influence landings include harvesting effort, available habitar, stock abundance, localized plant growth and accessibility of areas to rakers. Since 1973, annual landings and effort have been icwest in Areas 7 and 8 (southern edge of Warren Cove). In 1979, no harvesting was conducted in Area 8, while Area 7 was worked for approximately 30 minutes, yielding 70 lbs of moss. Low utilization of Areas 7 and 8 may be due to two factors: poorer marketable quality moss resulting from stunted growth and high degree of epi-phyti:ation, and their greater distance from the landing site. Pakers preferred I to work proximately to the landing area despite seasonal stock declines from intense harvesting. Areas 4, 5 and 6 are adjacent to PNPS. Preoperational landings (1971 and 1972) for these areas (pooled data) represented 38.9% and 35.3%, respect-ively, of the total seasonal harvests. This year, landings for the afore-mentioned areas comprised 36.1% of the total harvest. Similarity in temporal production, and an increase in harvest rate of 26.4% from 1978 for Area 5 indi-cates that PNPS operation had no adverse effect on the local Irish moss resource. I OTTER TRAWL A trawl survey of benthic finfish populations was conducted in the en-virons of PNPS throughout the year. Five stations were sampled utilizing standard 20 minute tows (Figure 4). Stations 4 and 5 were added to the sampling regime in 1979 to expand spatial coverage of the study area and to provide additional reference sites for comparison with the existing surveillance station (Station 2). Single tows were generally made at each station because of time constraints. Whenever possible, to improve precision, a second tow .I 13 l
3 I 70038' l v I 'n )lf \\ p V __A.20 ,
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, e-ee mr-p5 ' g naa m a n m a E l b ~ " " "'I TRAWL STAT ION S"i g nouncar snes o i i o i z n k l ' u 1 I "-~" i::::i: J' n ;i c e :n a . I l
5 I
, I
I was conducted at Station 2 or at other locations. We did not lengthen our sampling day because possible diel effects could bias our results. Severe ice conditions in February prevented sampling the entire study area. No collections were made in April because of vessel haulage for annual maintenance. Trawl data for numerically dominant species were summarized. Abundance estimates were derived from catch per unit effort (CPUE) data, i.e. mean catch (number of fish) per tow. A species checklist of all finfish collected by trawl and gill net or observed in diving operations is presented in Table 4 A total of 8,126 fish comprising 27 species was collected in 111 tows. I A threespine stickleback was captured for the first time in the study. Six taxa: rinter flounder (43.8%), skate spp. (19.1%), yellowtail flounder (15.8%), windowpane (10.5%), longhorn sculpin (4.3%), and ocean peut (3.0%) accounted for 96. 5% of total catch. An identical dominance pattern to that observed in 1977 and 1978 occurred this year in the study area. Rank of abundance for dominant groundfish remained unchanged, and percent catch composition was similar. However, mean annual CPUE of all species combined for pooled stations increased substantially from 37.0 in 1977 and 27.0 in 1978 to 73.2 for 1979. Winter flounder ranked first in total catch. CPUE data indicate that annual abundance was greatest at Station 1 and lowest at Station 2 (Tables 5a and b ) . In 1979, mean CPUE increased at sites (Stations 1-3) also sampled in 1978 (Table 6). Overall, CPUE (pooled stations' data) increased from 10.6 in 1978 to 32.0 in 1979. The latter index value represents the largest study area mean recorded during postuperational years. As an index of relative abundance, our data reflect increased stock den-sity of winter flounder in the study area for 1979. A. B. Howe (pers. commun.)1 , l 1 A .B. Howe, Massachusetts Division of Marine Fisheries, 18 Heritage Professional Building, Rte 6A, Sandwich, Massachusetts 02563. I
~
15
I Table 4 Check list of finfish species (following classification of American Fisheries Society, 1970) collected or observed in the adjacent waters of Pilgrim Station, January - December, 1979. Class: Chondrichthyes l Order: Squaliformes W Family: Carcharhinidae - requiem sharks Mustelus canis (Mitchill) - smooth dogfish Order: Rajiformes Family: Pajidae - skates Raja sg . - skate spp. Class: Osteichthyes Order: Clupeiformes Family: Clupeidae - herrings g Alosa aestivalis (Mitchill) - blueback herring 3 Alosa sapidissima (Wilson) - American shad
~
Alosa pseudoharenzus (Wilson) - alewife Brevoortia tyrannus (Latrobe) - Atlantic menhaden Clupea harengus harengus (Linnaeus) - Atlantic herring Order: Salmoniformes Family: Osmeridae - smelts Osmerus mordax (Mitchill) - rainbow smelt g Order: Lophiiformes g Family: Lophiidae - goosefishes Lophius americanus (Valenciennes) - goosefish Order: Gadiformes Family: Gadidae - codfishes 3 Gadus morhua (Linnaeus) - Atlantic cod Merluccius bilinearis (Mitchill) - silver hake g Microgadus toccod (Walbaum) - Atlantic tomcod Pollachius virens (Linnaeus) - pollock Urophycis sg . - hake spp. Family: Zoarcidae - eelpouts Macro::carces americanus (Bloch and Schneider) - ocean pout Order: Gasterosteiformes Family: Syngnathidae - pipefishes and seahorses Svngnathus fuscus (Storer) - northern pipefish Family: Gasterosteidae - sticklebacks Gasteresteus aculeatus (Linnaeus) - threespine stickleback I 16
Order: Atheriniformes r Family: Atherinidae - silversides L Menidia menidia (Linnaeus) - Atlantic silverside Order: Perciformes { Family: Percichthyidae - temperate basses Morone saxatilis (Walbaum) - striped bass - f Family: Pomatomidae - bluefishes L Pomatomus saltatrix (Linnaeus) - bluefish Family: Scombridae - mackerels and tunas ( Scomber scombrus (Linnaeus) - Atlantic mackerel Family: Sparidae - porgies Stenotomus chrysops (Linnaeus) - scup { Family: Sciaenidae - drums Cynoscion regalis (Bloch and Schneider) - weakfish Family: Labridae - wrasses Tautoga onitis (Linnaeus) - tautog Tautogolabrus adspersus (Walbaum) - cunner Family: Pholidae - gunnels Pholis g el bs (Linnaeus) - rock gunnel Family: Stromateidae - butterfishes Peprilus triacanthus (Peck) - butterfish [ Family: Triglidae - searobins Prionotus carolinus (Linnaeus) - northern searobin Family: Cottidae - sculpins Hemitripterus americanus (Gmelin) - sea rabin Myoxocephalus aenaeus (Mitchill) - grubby Myoxocephalus octodecemspinosus (Mitchill) - longhorn sculpin Family: Cyclopteridae - lumpfishes and snallfishes Cyclopterus lumpus (Linnaeus) - lumpfish Liparis atlanticus (Jordan and Evermann) - ceasnail Order: Pleuronectiformes Family: Bothidae - lefteye flounders Paralichthys obloncus (Mitchill) - fourspot flounder Scophthalmus aquesus (Mitchill) - windowpane Family: Pleuronectidae - righteye flounders Limanda ferruginea (Storer) - yellowtail flounder Pseudopleurorectes americanus (Walbaum) - winter flounder ( Hippoglossoide.s, platessoides (Fabricius) - American plaice N [ f --
i i Table Sa. Trawl catch data at stations 1-3, 1979 Important commercial species Winter flounder (Pseudopleuronectes americanus) Station 1 (Warren Cove) Station 2 (30' Contour) Station 3 (40' Contour) Tow # Size Tow # Size Tow # Size Date # Fish Range (mm) Mean(mm) # Fish Range (mm) Mean(mm) # Fish Range (mm) Mean(mm) 1/10 1 1 317 317.0 1 0 1 8 251-418 332.8 2 2 319-332 325.5 3/1 1 3 347-389 367.0 1 3 290-340 313.3 1 4 281-466 361.0 2 1 279 279.0 i 3/22 1 8 82-395 209.6 1 13 100-353 263.3 1 17 92-445 299.3 2 12 122-337 267.8 e) 5/1 1 12 120-378 257.4 1 12 100-375 252.2 1 5 105-241 164.4 2 18 120-370 5/15 1 29 86-345 263.6
- 1 5 135-349 197.2 5/22 1 21 215-346 269.7 1 11 179-350 286.4 1 10 92-313 205.1 2 9 122-329 252.2 6/15 1 77 133-363 272.4 1 44 135-405 275.6 1 40 121-328 249.2 2 31 126-374 255.4 ,
I 6/21 1 111 115-370 256.0 1 31 138-320 272.0 1 16 106-336 200.8 2 61 160-372 257.5 2 35 118-357 260.8 7/10 *
- 1 24 125-312 239.2 2 26 137-325 238.9 m W W M M M M W M M M M M M M M W W W
Table Sa. Trawl catch data at stations 1-3, 1979 (cont.) Important commercial species Winter flounder (Pseudopleuronectes americanus) Station 1 (Warren Cove) Station 2 (30' Contour) Station 3 (40' Contour) Tow # Size Tow # Size Tow # Size Date # Fish Range (mm) Mean(mm) # Fish Range (mm) Mean(mm) # Fish Range (mm) Mean(mm) 7/24 1 75 148-332 254.0
- 1 53 118-355 238.4 2 88 116-328 231.0 2 57 115-341 239.0 8/7 1 64 136-359 269.4
- 1 11 135-291 236.0 2 60 171-336 258.1 2 29 160-296 217.7 35 156-331 272.5 *
- 8/20 1 2 29 160-306 250.1 "o
8/21
- 1 32 190-312 269.7 1 16 172-316 249.2 2 44 223-332 265.5 9/10 *
- 1 11 182-468 309.0 2 7 150-340 201.9 9/26 1 64 215-358 287.0 1 31 140-366 281.3 1 40 172-362 284.0 s 2 87 172-359 288.5 2 24 202-341 289.6 10/19 1 76 77-332 284.1 1 15 278-356 311.5 2 66 190-369 284.8 2 15 253-341 291.5 10/29 1 143 166-340 296.1 1 42 181-370 307.6 2 36 190-361 300.1 10/31 1 115 163-369 298.6
- 1 24 180-366 279.2 2 81 194-396 299.7 2 34 255-347 293.1 11/8 1 27 229-365 305.0 1 27 166-400 312.0 1 45 176-472 298.7 2 25 186-418 315.6
Table Sa. Trawl catch data at stations 1-3, 1979 (cont.) Importa :t commercial species Winter flounder (Fseudopleuronectes americanus) Station 1 (Warren Coves Station 2 (30' Contour) Station 3 (40' Contour) Tow # Size Tow # Size Tow # Size Date # Fish Range (mm) Mean(mm) # Tish Range (mm) Mean(mm) # Fish Range (mm) Mean(mm) 11/19 1 21 200-361 306.7 1 22 281-382 301.1 1 16 270-329 291.6 2 18 201-362 293.6 2 11 270-341 299.6 . 12/5 1 7 276-342 299.9 1 13 205-397 305.8 1 21 281-386 303.5 Total 26 1379 26 535 24 543 Catch / tow 53.0 20.6 22.6
's
- No sample taken because of sea conditions or interference with commercial lobster gear.
m M M M M M m m m' a m m m e m mm e m Table 5b. Trawl catch data at stations 4 and 5, 1979 Important conanercial species Winter flounder (Pseudopleuronectes americanus) Station 4 (Rocky Point) Station 5 (White llorse) Tow # Size Tow # Size Date # Fish Range (nm) Mean(mm) # Fish Range (mm) Mean(mm) 1/10 1 0 1 2 190-305 247.5 3/1 1 3 305 305.0 1 2 258-315 286.5 3/22 1 16 77-380 198.9 1 5 100-485 302.0 5/1 1 13 118-410 262.7 1 18 118-323 224.0 5/15 1 24 95-335 240.0
- 5/22 1 15 144-381 267.3 1 11 148-345 217.2 6/15 1 59 111-360 257.6 1 34 130-382 247.0 6/21
- 1 31 108-340 256.7 7/10
- 1 51 134-338 225.8 2 54 135-304 216.0 7/24
- 1 37 158-281 229.3 2 58 135-318 221.0 8/7 1 49 154-311 230.0 2 68 145-290 237.4 8/21
- 1 41 112-308 216.9 2 26 146-304 217.9
Table 5b. Trawl catch data at stations 4 and 5,:1979 (cont.) Important commercial species Winter flounder (Pseudopleuronectes americanus) Station 4 (Rocky Point) Station 5 (White Horse) Tow # Size Tow #, Size Date # Fish Range (mm) Mean(mm) # Fish Range (mm) Mean(mm) 9/10 1 35 245-371 286.0 1 53 163-360 264.9 2 24 175-326 281.1 2 44 136-357 267.3 9/26
- 1 70 112-370 284.0 10/19 1 44 165-343 289.2
- 10/29 1 77 220-340 297.9
- _y 10/31 1 62 180-374 293.1
- 11/8 1 31 181-336 '89.5 1 15 263-335 292.4 11/19 1 16 148-341 282.7
- 12/5 1 12 115-355 277.9 1 0 Total 15 431 20 669 Catch / tow 28.7 33.5 l
- No sample taken because of sea conditions or interference with commercial lobster gear.
M M M M M M M M M M M M M m M W W W W
I Table 6. Mean annual catch per 20 minute tow for winter flounder at stations sampled in the adjacent waters of P!GS. I Station I #1 #2 Warren Cove 30' Contour
#3 #4 #5 40' Contour Rocky Point White Horse Pooled Year # Tows Mean # Tows Mean # Tows Mean # Tows Mean # Tows Mean # Tows Mean 1970 42 85.0 42 32.7 39 26.7 - - - - 123 48.7 1971 43 77.0 42 30.1 42 16.8 - - - - 127 41.6 1972 41 41.2 41 26.0 41 19.9 - - - - 123 29.0 I 1973 22 41.2 22 18.4 22 11.9 - - - - 66 23.8 '
1974 44 12.5 40 7.8 42 8.7 - < - - - 126 9.8 1975 45 10.9 38 10.7 45 6.4 - - - - 128 9.3 l'976 39 23.3 28 8.1 39 8.5 -- - - - 106 13.8 j 1977 31 27.7 21 8.5 30 9.6 - - - - 82 16.0 I 1978 35 11.4 23 8.0 37 11.5 - - - - 95 10.6 1979 26 53.0 26 20.6 24 22.6 15 28.7 20 33.5 111 32.0 I I I 'I I ,I l I ' I I e
I in a coast-wide DMF trawl assessment of fish stocks, supported our findings. From combined spring and fall cruise data, collected in the vicinity of PNPS, he found a CPUE weight increase of 56% and numerical increase of 39% from I 1978 to 1979. Total catch and annual mean CPUE for skate spp. were similar at Stations 1 and 2 (Tables 7-11). Relative abundance was highest at these stations. CPUE by station and for combined stations increased from 1978 levels and were the highest values obtained since the study's inception (Table 12). Stock density estimates increased from 5.4 (1978) to 14.4 (1979) - an increase of 167%. The 1979 stock index exceeds the mean (3.5) for preoperational years (1970-1972) by a factor of 4.1. Supportive of our findings, A.B. Howe, mentioned above, reported an increase in CPUE of 110% by weight and 243% by number from 1978 to 1979. l Largest catches of yellcwtail flounder were obtained from Station 3 (Tables 13 a and b). Mean pooled CPUE had declined frem 5.3 in 1977 to 4.1 in 1978 but increased in 1979 to 11.6, which is the second highest value recorded for this species in the entire study (Table 14). In contrast to our findings, A.B. Howe reported virtually no change in yellowtail flounder abun-dance indices for that area from 1978 to 1979. Total catch of windowpane was highest at Station 1 followed by Station 2 (Tables 7-11). Mean CPUE by station increased from 1978 levels (Table 15). Overall, annual CPUE rose from 2.5 (1978) to 7.7 (1979). Prior to 1979, our data indicate that windowpane relative abundance did not appreciably change throughout the study area. However, our work and that of A.B. Howe's for 1979 reflect an overall increase in CPUE of 208% and 189%, respectively from 1978 levels. I I 24
i Table 7. Trawl catch data, 1979 Dominant community species Station 1 (Warren Cove) I Windowpane Ocean pout Skates Longhorn sculpin (Scophthalmus (Macrozoarces (Raja (Myoxocephalus 'g E Date Tow aquosus) americanus) g .) octodecemspinosus) 0 0 0 1/10 1 0 0 0 0 3/1 1 0 1 4 1 3/22 1 0 3 3 3 5/1 1 9 0 5 6 5/15 1 8 0 37 1 5/22 1 11 0 6 0 6/15 1 3 ! 6/21 1 28 0 60 5 2 5 1 17 2 7/10
- 7/24 1 0 1 52 15 )
13
,g 2 2 0 34 l
5 7 0 50 6 ) 8/7 1 2 1 0 17 3 0 44 0 8/20 1 18 2 13 0 42 0 8/21
- 0 37 0 9/26 1 22 2 9 0 14 0 0 14 5 10/B 1 13 4
2 10 0 9 0 10 7 10/29 1 11 12 0 22 2 10/31 1 0 25 5 2 21 0 0 4 11/8 1 15 I I 2e
l Table 7. Trawl catch data, 1979 (cont.) Dominant community species Station 1 (Warren cove) Ocean peut Skates Longhorn sculpin I Windowpane (Scophthalmus (Macrozoarces (Raja (Myoxocephalus Date Tow aquosus) americanus) sg. ) octodecemspinosus) 32 0 0 2 11/19 1 34 0 1 2 2 14 0 3 0 12/5 1 Total 26 298 6 506 86 Catch / tow 11.5 0.2 19.5 3.3
- No sample taken because of sea conditions or interference with commercial lobster gear.
i I I I I I I I i I I I e I
I Trawl catch data, 1979 l Table 8. Dominant community species Station 2 (30' Contour) Windowpane Ocean pout Skates Lenghorn sculpin i (Raja (Myoxocephalus (Scophthalmus (Macrozoarces iI I Date Tow acuosus) americanus) spp.) octodecemspinosus) l l I 1/10 1 2 0 2 0 0 0 0 0 0 3/1 0 I 1 0 0 0 . 2 0 0 0 0 l l 3/22 1 0 1 2 2 2 1 0 8 0 5/1 1 8 63 5 3 . 2 10 35 9 5 43 l 5/22 1 8 15 5 2 11 47 44 6 l '" 6/15 1 13 2 56 5 2 7 1 58 10 6/21 1 0 6 40 11 l 2 4 0 46 7 l 7/10
- i 7/24
- I i
8/7
- l 8/20 * )
8/21 1 12 0 46 0 2 12 0 54 0 lI 9/10
- I 9/26 1 18 0 15 1 10/19 1 13 0 17 10 2 13 0 13 7 30 0 13 7 10/29 1 2 17 0 15 5 7 0 a 3 1 11/8 1 2 19 2 8 6 l
!I lI 27 l
I: i Table 8. Trawl catch data, 1979 (cont.) Dominant community species Station 2 (30' Contour) I Windowpane Ocean peut Skates Longhorn sculpin (Scophthalmus (Macrozoarces (Raja (Myoxocephalus 3 Date Tow aquosus) americanus) sg. ) octodecemspinosus) 5 j 11/19 1 10 2 15 2 1 2 21 2 16 2 12/5 1 11 0 0 0 Total 26 246 176 527 97 Catch / tow 9.5 6.8 20.3 3.7
- No sample taken because of sea conditions or interference with commercial lobster gear.
I I I I I I ! I l. ,- g I
l i I I Table 9. Trawl catch data, 1979 Dominant community species Station 3 (40' contour) Windowpane Ocean peut Skates Longhorn sculpin 1 l (Scophthalmus (Macrozoarces (Raia (Myoxecechalus l Date Tow aquesus) americanus) g. ) octodecemspinosus) 1 I 1/10 3/1 1 1 0 0 0 0 0 0 1 0 l l 3/22 1 1 1 0 2 5/1 1 0 5 0 2 l 5/15 1 0 3 1 6 5/22 1 1 1 16 5 6/15 1 1 2 8 12 l 6/21 1 0 0 9 7 7/10 1 0 0 1 4 I 7/24 2 1 2 0 2 0 2 6 7 14 1 l 2 1 1 9 13 8/7 1 0 0 3 5 2 0 1 0 4 8/20
- 8/21 1 2 0 23 1 9/10 1 0 0 7 1 2 0 0 4 1 9/26 1 23 0 19 0 2 4 0 21 1 10/19
- 10/31 1 5 3 23 0 2 1 4 15 6 11/8 1 5 7 5 9 11/19 1 17 0 4 1 I -
lI 2e
i
! Table 9. Trawl catch data, 1979 (cont.)
Dominant community species Station 3 (40' Contour) I Windowpane Ocean pout Skates Longhorn sculpin Date Tow (Scophthalmus (Macrozoarces (Raja (Myoxocephalus aquosus) americanus) sg. ) octodecemspinosus) 12/5 1 12 2 7 0 = Total 24 75 32 183 102 I' Catch / tow 3.1 1.3 7.6 4.2
- No sample taken because of sea conditions or interference with commercial l lobster gear.
l I I I I I i 3 I I I I 3 I
I Table 10. Trawl catch data, 1979 Dominant community species Station 4 (Rocky Point) I Windowpane Ocean pout Skates Longhcrn sculpin (Scophthalmus (Macrozoarces (Raja (Myoxocephalus Date Tow aquosus) americanus) g. ) octodecemspinosus) 1/10 1 0 0 0 1 3/1 1 0 0 0 0 3/22 1 0 0 1 1 5/1 1 4 18 0 2 5/15 1 1 0 6 0 5/22 1 5 7 17 1 6/15 1 0 2 8 17 6/21 7/10
- 7/24
- 7/21
- 9/10 1 18 0 16 1 2 11 0 16 0 9/26
- 10/19 1 31 0 18 7 10/29 1 12 0 10 8 10/31 1 12 0 34 4 11/8 1 16 0 0 7 l 11/19 1 22 1 2 3 12/5 1 7 0 3 2 l lI
- s. _ _, -
l Total 15 139 ?- 131 54 Catch / tow 9.3 1.9 8.7 3.6 i
- I
- No sample taken because of sea conditions or interference with commercial lobster gear.
31 .I
Il Table 11. Trawl catch data, 1979 l m Dominant community species Station 5 (White Horse) Windowpane Ocean pout Skates Longhorn sculpin l Date Tow (Scophthalmus (Macrozoarces (Raja (Myoxocephalus aquosus) americanus) spo.) octodecemscinosus) 1/10 1 0 0 0 0 3/1 1 0 0 0 0 3/22 1 0 0 0 0 5/1 1 4 0 5 5 5/22 1 5 2 50 0 6/15 1 8 0 31 0 6/21 1 11 0 36 0 7/10 1 12 0 3 1 2 7 0 2 0 7/24 1 16 0 18 0 2 8 0 6 0 8/7 1 6 0 1 0 l 2 5 0 1 0 W 8/21 1 0 0 13 0 g 2 1 0 20 0 5 9/10 1 2 0 3 1 2 0 0 8 0 9/26 1 4 0 4 0 10/19
- 11/8 1 5 0 5 5 11/19
- 12/5 1 3 0 0 0 i Total 20 97 2 206 12 l Catch / tow 4.8 0.1 10.3 0.6
- No sample taken because of sea conditions or interference with commercial lobster gear. ;
*l l
32
I Table 12. Mean annual catch per 20 minute tow for skate spp. at stations sampled in the adjacent wa-ters of PNPS. Station
#1 #2 #3 #4 #5 Warren Cove 30' Contour 40' Contour Rocky Point White Horse Pooled # Tows Mean # Tows Mean # Tows Mean # Tows Mean Year # Tows Mean # Tows Mean 42 3.8 42 4.7 39 2.4 - - - - 123 3.7 1970 42 42 2.7 - - - - 127 3.7 1971 43 3.4 5.1 41 3.6 41 1.8 - - - 123 3.1 1972 41 3.8 22 2.7 22 0.5 - - - - 66 2.0 1973 22 2.7 44 40 1.8 42 1.4 - - - - 126 2.7 1974 4.8 45 3.9 38 2.2 45 1.1 - - - - 128 2.4 1975 39 28 3.1 39 1.7 - - - - 106 3.6 1976 6.0 21 4.7 30 4.7 - - - 82 7.9 1977 31 13.1 -
35 6.0 23 3.6 37 6.0 - - - - 95 5.4 1978 26 19.5 26 20.3 24 7.6 15 8.7 20 10.3 111 14.4 I 1979 I I I I I I I I 33
Table 13a. Trawl catch data at stations 1-3, 1979 Important commercial species Yellowtail flounder (Limanda ferruginea) Station 1 (Warren Cove) Station 2 (30' Contour) Station 3 (40' Contour) Tow # Size Tow # Size Tow # Size Date # Pish Range (mm) Mean(mm) # Tish Range (mm) Mean(mm) # Fish Range (mm) Mean(mm) 1/10 1 0 1 0 1 0 2 1 362 362.0 3/1 1 0 1 0 1 0 2 0 3/22 1 2 120-175 147.5 1 1 190 190.0 1 1 362 362.0 2 0 Y 5/1 1 3 295-357 334.7 1 5 120-368 263.6 1 2 349-414 381.5 2 4 204-346 291.2 5/15 1 9 86-374 248.0 1 2 137-235 186.0 5/22 1 12 75-288 158.2 1 7 122-338 236.3 1 4 83-310 182.8 2 5 146-320 267.4 6/15 1 13 100-335 236.5 1 34 103-362 207.0 1 13 120-340 231.3 l 2 36 108-325 186.6 ! 6/21 1 22 122-305 233.8 1 19 110-344 168.3 1 23 91-318 197.9 2 15 116-303 159.3 2 23 103-296 155.8 7/10 *
- 1 26 111-350 228.4 2 48 119-324 210.3 7/24 1 24 115-315 211.3 !* 1 95 111-320 204.3 2 19 110-300 176.3 2 109 125-423 203.7 i
l l l E _ _
M M M M M M M M m M M M M M M M M M Table 13a. Trawl catch data at stations 1-3, 1979 (cont.) Important commercial species Yellowtail flounder (Limanda ferruginea) Station 1 (Warren Cove) Station 2 (30' Contour) Station 3 (40' Contour) Tow # Size Tow # Size Tow # Size Date # Pish Range (mm) Mean(mm) # Pish Range (mm) Mean(mm) # Pish Range (mm) Mean(mm) 8/7 1 39 129-333 245.1
- 1 57 128-331 234.4 2 35 132-329 2 25 116-337 209.7 8/20 1 2 270-293 281.5 *
- 2 0 8/21
- 1 15 175-315 258.3 1 8 140-280 182.6 2 16 156-327 231.3
- N 9/10
- 1 5 125-167 152.6 2 7 137-181 157.0 9/26 1 6 175-335 237.7 1 11 160-335 272.4 1 12 147-385 253.0 2 4 205-313 238.0 2 14 150-330 206.6 10/19 1 12 206-331 283.8 1 1 240 240.0
- 2 11 187-337 300.0 2 0 10/29 1 17 183-390 301.4 1 12 195-392 266.9 2 5 112-350 221.5 10/31 1 24 233-412 312.3 1 1 192 192.0 2 27 200-375 297.7 2 5 194-238 208.8 11/8 1 4 262-444 345.3 1 23 175-345 287.2 1 6 76-340 235.8 2 23 210-375 282.9 11/19 1 7 251-356 326.9 1 5 172-338 268.6 1 3 181-237 213.3 2 4 202-265 228.3 2 1 332 332.0
Table lla.t Trawl catch data at stations 1-3,1979 (cont. ) Important commercial species Yellowtail flounder (Limanda ferruginea) Station 1 (Warren Cove) Station 2 (30' Contour) Station 3 (40' Contour) Tow # Size Tow # Size Tow # Size Date # Pish Range (mm) Mean(mm) # Fish Range (mm) Mean(mm) # Fish Range (mm) Mean(mm) 12/5 1 3 242-358 317.3 1 3 316-353 331.0 1 6 174-313 230.8 Total 26 314 26 250 24 472 Catch / tow 12.1 9.6 19.7
$
- No samples taken because of sea conditions or interference with commercial lobster gear.
i
m M M M M M M M M M M M M M M M M M M Table 13b. Trawl catch data at stations 4 and 5, 1979 Important commercial species Yellowtail flounder (Limanda ferruginea) Station 4 (Rocky Point) Station 5 (White Horse) Tow # Size Tow # Size Date # Fish Range (mm) Mean(mm) # Fish Range (mm) Mean(mm) 1/10 1 0 1 1 178 178.0 3/1 1 0 1 0 3/22 1 3 88-180 121.7 1 1 215 215.0 5/1 1 2 114-223 168.5 1 3 118-389 292.3 g 5/15 1 7 98-384 171.3 5/22 1 3 110-148 126.3 1 14 121-326 247.7 6/15 1 14 115-330 154.4 1 9 118-285 237.2 6/21
- 1 11 132-320 270.0 7/10
- 1 33 164-382 270.0 2 15 147-327 247.7 7/24
- 1 15 170-310 212.6 2 18 175-285 231.1 8/7
- 1 8 172-290 232.4 2 6 172-232 194.0 8/21
- 1 1 220 220.0 2 7 202-275 245.4 9/10 1 4 191-204 197.5 1 8 190-319 288.6 2 4 166-210 183.3 2 3 200-301 240.7
Table 13b. Trawl catch data at stations 4 and 5, 1979 (cont.) Important commercial species Yellowtail flounder (Limanda ferruginea) Station 4 (Rocky Point) Station 5 (White Horse) Tow # Size Tow # Size Date # Fish Range (mm) Mean(mm) # Fish Range (mm) Mean(mm) 9/26
- 1 11 217-341 281.6 10/19 1 7 211-322 271.3
- 10/29 1 1 256 256.0 10/31 1 7 198-425 278.9 11/8 1 6 215-426 279.0 1 14 22E-360 304.2 S 11/19 1 9 82-369 237.1
- 12/5 1 2 112-209 160.5 1 1 356 356.0 Total 15 69 20 179 Catch / tow 4.6 9.0
- No samples taken because of sea conditions or interference with commercial lobster gear.
M M M M M M M M M M M M M M M M M M M
! 1 ll ! l i i I Table 14 Mean annual catch per 20 minute tow for yellow- !lW tail flounder at stations sampled in the adja-cent waters of PNPS. , I Station
#1 #2 #3 #4 #5 Warren Cove 30' Contour 40' Contour Rocky Point White Horse Pooled Year # Tows Mean # Tows Mean # Tows Mean # Tows Mean # Tows Mean # Tows Mean 1970 42 6.8 42 7.1 39 8.6 - - - -
123 7.5 1971 43 5.2 42 14.5 42 16.4 - - - - 127 12.0 1972 41 4.0 41 4.0 41 7.9 - - - - 123 5.3 1973 22 2.8 22 5.1 22 7.8 - - - - 66 5.3 l l 1974 44 1.5 40 1.8 42 5.9 - - - - 126 3.1 1975 45 2.2 38 6.6 45 5.8 - - - - 128 4.8 l I 1976 39 4.7 29 9.2 39 11.3 - - - - 106 8.3 I i 1977 31 4.6 21 2.5 30 8.0 - - - - 82 5.3 1978 35 2.2 23 3.6 37 6.2 - - - - 95 4.1 1979 26 12.1 26 9.6 24 19.7 15 4.6 20 9.0 111 11.6 I I .I I (I 'I lI 39
I l Table 15. Mean annual catch per 20 minute tow for window- ll pane at stations sampled in the adjacent waters = of PNPS. Stat i on I
#1 #2 #3 #4 #5 Warren Cove 30' Contour 40' Contour Rocky Point White Horse Pooled Year # Tows Mean # Tows Mean # Tows Mean # Tows Mean # Tows Mean # Tows Mean 1970 42 4.4 42 3.6 39 1.9 - - - -
123 3.3 1971 43 4.9 42 2.9 42 1.8 - - - - 127 3.2 1972 41 4.3 41 3.7 41 1.4 - - - - 123 3.1 1973 22 4.0 22 3.0 22 1.3 - - - - 66 2.7 1974 44 2.6 40 1.9 42 1.5 - - - - 126 2.0 1975 45 4.4 38 3.7 45 2.4 - - - - 128 3.5 1976 39 7.1 28 2.7 39 2.5 - - - - 106 4.3 1977 31 5.3 21 2.3 30 3.1 - - - - 82 3.7 1978 35 3.8 23 2.0 37 1.5 - - - - 95 2.5 26 1.5 24 3.1 15 9.3 20 4.8 111 7.7 I 1979 26 11.5 I I I I I. l I I 4e I
I Abundance distribution of longhorn sculpin was similar at all stations except Station 5 (Tables 7-11). CPUE had declined in the postoperational years of 1973-1977 but increased in 1978 and again in 1979 (Table 16). Ocean peut were more abundant at Station 2 than at other sites (Tables 7-11). Overall abundance declined from the beginning of the study in 1970 through 1977. CPUE decreased 97% during that period but increase.J slightly in 1978 and 1979 (Table 17). In summation, no adverse PNPS effect is evident for 1979 from the afore-mentioned analyses of groundfish data. In fact, CPUE generally increased for dominant species at all stations sampled. I GILL NET As sea conditions allowed, biweekly overnight gill net sets were made on station (Figure 5). From January to mid-August, pelagic fish and groundfish frequenting the ledges bracketing PNPS were sampled employing identical gear and me thodolc ;y used in past years. To more representative 1y sample larger fish which would further reduce gear selectivity, we added two 30.5 m (100 ft) panels of larger mesh sizes to our experimental gill net in late August. This increased the overall length of the net to 213.4 m (700 ft). Mesh sizes now include: 3.8, 5.1, 6.4, 7.6, 8.9, 11.4, and 15.2 cm (1 1/2, 2, 2 1/2, 3, 3 1/2, 4 1/2 and 6 incbi-stretch measure. Records were initially differentiated by mesh size. Data were later pooled for the 3.8-8.9 cm panels to allow inter-year comparisons with past records. Lengths of fish are recorded as total length (TL) or fork length (FL). A total of 4,418 fish comprising 26 species was collected from 19 sets of the net (Table 18). An additional 78 fish were captured in the 11.4 and 15.2 l I em panels (pooled data) from the end of August through December. Two new l l l 1 1 ' I
I'
~
Table 16. Mean annual catch per 20 minute tow for long-horn sculpin at stations sampled in the adj a-cent waters of PNPS. Station I
#1 #2 #3 #4 #5 Warren Cove 30' Contour 40' Contour Rocky Point White Horse Pooled Year # Tows Mean # Tows Mean # Tows Mean # Tows Mean # Tows Mean # Tows Mean 1970 42 3.4 42 7.8 39 20.0 - - - -
123 10.2 1971 43 2.5 42 5.8 42 10.0 - - - - 127 6.1 1972 41 4.8 41 6.5 41 9.5 - - - - 123 7.0 1973 22 2.3 22 3.7 22 10.0 - - - - 66 5.3 1974 44 1.7 40 2.0 42 3.8 - - - - 126 2.5 1975 45 0.8 38 0.9 45 1.5 - - - - 128 1.1 1976 39 0.5 28 0.2 39 1.5 - - - - 106 0.8 1977 31 0.3 21 0.1 30 1.3 - - - - 82 0.6 19'/8 35 0.6 23 0.9 37 1.6 - - - - 95 '.1 1979 26 3.3 26 3.7 24 4.2 15 3.6 20 0.6 111 3.2 I I I I I I I
I Tabic 17. Mean annual catch per 20 minute tow for ocean peut at stations sampled in the adjacent wa-- ters of PNPS. I Station
#1 #2 #3 #4 #5 Warren Cove 30' Contour 40' Contour Rocky Point White Horse Pooled Year # Tows Mean # Tows Mean # Tows Mean # Tows Mean # Tows Mean # Tows Mean 1970 42 12.5 42 25.4 39 9.8 - - - -
123 16.0 1971 43 9.5 42 17.1 42 6.6 - - - - 127 11.1 1972 41 4.2 41 8.8 41 5.5 - - - - 123 6.2 1973 22 2.9 22 10.1 22 3.9 - - - - 66 5.6 126 2.9 I 1974 44 2.2 40 4.0 42 2.7 - - - - 1975 45 1.6 38 4.3 45 2.2 - - - - 128 2.6 1976 39 0.7 28 3.7 39 0.9 - - - - 106 1.6 1977 31 0.2 21 1.0 30 0.5 - - - - 82 0.5 I 1978 35 0.1 23 2.9 37 0.5 - - - - 95 0.9 1979 26 0.2 26 d6.8 24 1.3 15 1.9 20 0.1 111 2.2 I I I I I I I 43 I - - - - - - - - - - - - - -
- _ . _ _ _ ._ i 4
I Gurnet Pt. I Plymouth Bay , I. Cape Cod Bay Il
's Warren Rocky Point
- Cove PNPs Pancmet I
Point g g \ Legend 3 SCALE g
----- Gill Net Station ' - Power Plant . . . .W 0 1/2 1 2 . .aurical F.i1es N . Figure 5. Gill net station location Rocky Point, Plymouth. gl 3
l l
1 I g , W Table 18. Numerical rank, number, and percent composition of finfish taken in the vicinity of PNPS by gill net (five panels of 3.8 - 8.9 cm mesh) in 1979.
. Percent of Rank Species No. total catch
- 1. pollock 1,652 37.4
- 2. Atlantic herring 1,064 24.1
- 3. cunner 734 16,6 4 Atlantic menhaden 154 3.5
- 5. Atlantic cod 124 2.8
- 6. blueback herring 93 2.1
- 7. alewife 90 2.0
- 8. Atlantic mackerel 70 1.6 1
- 9. northern searobin 65 1.5
- 10. bluefish 61 1.4
- 11. tautog 58 1.3
- 12. Atlantic tomcod 35 0.8
- 13. sea raven 34 0.8 14 smooth dogfish 32 0.7
- 15. rainbow smelt 31 0.7
- 16. longhorn sculpin 30 0.7 I 17.
18. winter flounder butterfish 24 23 0.5 0.5 hake spp. 23 0.5
- 19. grubty 7 0.2 j 20. striped bass 4 0.1 skate spp. g 0.1 l
i
- 21. American shad 3 0.1 I
45
Table 18. :;umerical rank, number, and percent composition (cont.) of finfish taken in the vicinity of PNPS by gill net (five panels of 3.8 - 8.9 cm mesh) in 1979. Percent of Rank Species No. total catch
- 22. northern pipefish 1 American plaice 1 weakfish 1 0.1 Total 4,418
~
I I l I I I I I I l 5 I 46
I species - weakfish and American plaice, were captured this year. Pollock (37.4%), Atlantic herring (24.1%), and cunner (16.6%) were numerically domi-nant representing 78.1% of total catch. Mean catch per set (CPUE) for all species combined was 232.5, a 15% increase from last year's CPUE of 202.0. Pollock ranked first in total catch. Although collected in every month except March, their abundance was lowest January-April (Table 19). Only juveniles (119-458 mm FL), according to Steele (1963), were sampled in the vicinity of PNPS. Annual abundance estimates of pollock, derived from CPUE data, apparently reflect natural population fluctuations (Table 20). Arith-metic mean CPUE declined slightly from 91.3 in 1978 to 86.9 in 1979. Highest CPUE for pollock (141.8) was recorded in 1977, a postoperational year. Atlantic herring was the second most abundant species sampled (Table 18). Herring, ranging in size from 112-335 mm FL, were collected every season of the year but were less abundant from May-August (Table 19). As evidenced in Table 20, mean annual CPUE has fluctuated throughout the study. Abundance apparently declined in 1972 (preoperational) to a study low and peaked in 1976 (postoperational). Mean annual CPUE more than doubled from 1978 to 1979. Cunner ranked third in overall numerical importance (Table 18). Individuals, ranging in size from 105-302 mm TL, were collected from April-December (Table 19). Total catch and mean catch (Table 20) generally increased during the post-operational years of 1973-1978. However, mean annual CPUE declined frem 44.0 I in 1978 to 38.6 in 1979. The latter was nevertheless double the value of abun-dance estimates for preoperational years (1971-1972). Atlantic menhaden of 153-340 mm FL were captured from May-December (Table 19). CPUE has fluctuated throughout the study with the highest value recorded, to date, in 1979 (Table 20). lI .I !W 47
I Table 19. Gill net collections, 1979
& elected species Rocky Point, Plymouth pollock Atlantic herring cunner Size Size Size a Date No. Range (mm) No. Range (mm) No. Range (mm) 1/23-24 2 221-225 33 165-297 0 -
2/28-3/1 2 230-240 18 160-279 0 - 3/28-29 0 _ 4 252-262 0 - 4/11-12 6 180-235 27 210-320 1 180 5/8-9 239 202-280 0 - 3 140-204 5/21-22 86 119-285 0 - 46 115-210 6/4-5 93 230-442 2 125 83 121-289 6/21-22 35 240-458 4 235-289 94 105-288 7/2-3 80 203-440 0 - 81 113-302 7/16-17 40 139-318 1 307 80 125-283 8/8-9 29 148-310 0 - 37 123-203 8/20-21 73 150-327 0 - 116 126-240 9/u-5 41 147-348 3 231-262 38 111-250 9/20-21 122 149-355 66 179-318 75 120-219 10/2-3 83 153-351 1 262 29 121-181 10/15-16 130 150-405 206 168-335 37 121-220 11/1-2 116 152-405 362 112-320 9 125-165 11/20-21 163 159-385 162 154-334 4 122-143 12/10-11 312 163-395 175 194-306 1 175 Total 1652 -119-458 1064 112-335 734 105-302 Catch / set 86.9 56.0 38.6 I I 48 l
I i Table 19 . Gill net collections ,1979 (cont. ) Selected species Rocky Point, Plymouth I Atlantic menhaden Atlantic cod alewife Size Size Size Date No. Range (mm) No. Range (mm) No. Range (mm) 1/23-24 0 - 0 - 0 - 2/28-3/1 0 - 0 - 0 - 3/28-29 0 - 1 263 0 - 4/11-12 0 - 4 220-325 1 206 5/8-9 2 265-280 11 151-493 11 235-275 5/21-22 4 240-277 10 175-323 25 160-280 6/4-5 0 - 6 335-337 28 142-271 6/21-22 2 285-340 9 270-332 7 135-210 7/2-3 1 262 7 332-565 3 135-150 7/16-17 0 - 2 366 0 - 8/8-9 0 - 4 362-377 7 143-172 8/20-21 23 153-306 5 244-360 0 - 9/4-5 0 - 9 340-538 0 - 9/20-21 2 262-288 13 310-740 0 - 10/2-3 0 - 9 370-699 2 164-213 10/15-16 11 239-279 17 285-732 2 168-298 , 13/1-2 12 237-291 9 290-605 1 260 11/20-21 87 200-290 8 328-586 1 304 12/10-11 10 210-256 0 - 2 142-151 Total 154 153-340 124 151-740 90 135-304 Catch / set 8.1 6.5 4.7 l I l 49 ! l
I Table 19 Gill net collections,1979 (cont. ) Selected species Rocky Point, Plymouth blueback herring Atlantic mackerel tautog Size Size Size Date No. Range (mm) No. Range (mm) No. Range (mm) 1/23-23 0 - 0 - 0 - 2/28-3/1 0 - 0 - 0 - 3/28-29 0 - 0 - 0 - 4/11-12 0 - 0 - 0 - 5/8-9 0 - 0 - 2 246-343 5/21-22 0 - 1 387 3 186-271 6/4-5 0 - 12 261-403 0 - 6/21-22 0 - 31 252-448 6 206-292 7/2-3 0 - 0 - 0 7/16-17 1 194 0 - 8 229-308 8/8-9 0 - 1 256 3 228-240 8/20-21 4 148-180 0 - 10 220-479 9/4-5 0 - 0 - 12 220-328 9/20-21 0 - 0 - 11 231-470 10/2-3 0 - 0 - 2 259-420 10/15-16 0 - 2 410-415 1 236 11/1-2 0 - 2 252-272 0 - 11/20-21 87 75-236 17 240-403 0 - 12/10-11 1 162 4 315-400 0 - Total 93 75-236 70 240-448 58 186-479 Catch / set 4.9 3.7 3.0 I l 50
1 1 Table 19 . Gill net collections, 1979 (cont.) Selected species Rocky Point, Plymouth I northern searobin bluefish rainbow smelt Size Size Size Date No. Range (mm ) No. Range (mm) No. Range (mm) 1/23-24 0 -- 0 - 8 190-220 2/28-3/1 0 - 0 - 13 185-209 3/28-29 0 - 0 - 2 190-210 4/11-12 0 - 0 - 2 198-210 5/8-9 0 - 0 - 0 - 5/21-22 1
- O - 0 -
6/4-5 26
- 1 377 0 -
6/21-22 12
- O - 0 -
7/2-3 11
- O - 0 -
7/16-17 4
- 0 - 0 -
8/8-9 2
- O -
1 152 8/20-21 2
- 1 169 1 178 9/4-5 2
- O -
0 - I 9/20-21 2
- 23 180-211 0 -
10/2-3 2
- 6 194-211 0 -
10/15-16 0 - 29 180-258 0 - 11/1-2 0 - 0 - 0 - 11/20-21 0 - 0 - 1 216 12/10-11 1
- 1 251 3 209-217 Total 65
- 61 169-377 31 152-220 Catch / set 3.4 3.2 1.6
- No measurement taken.
51
I Table 2a Mean annual catch per standard gill net (five panels of 3.8 - 8.9 cm mesh) set (CPUE) for selected species collected in the vicinity of PNPS, 1971 - 1979. Atlantic Atlantic Atlantic I Year .pollock herring cunner menhaden cod alewife 1971 67.9 14.2 18.9 1.8 8.9 44.3 1972 119.8 1.5 18.6 0.8 14.2 10.8 1973 109.7 4.6 21.1 2.1 9.6 15.2 1974 69.1 19.9 18.9 4.9 7.9 29.6 1975 22.1 17.4 26.4 4.1 6.1 4.1 1976 57.2 96.1 27.6 6.4 4.4 12.2 1977 141.8 80.0 42.7 2.6 3.0 7.4 1978 91.3 22.3 44.0 6.4 2.8 14.5 1979 86.9 56.0 38.6 8.1 6.5 4.7 I I ( 1 I 1 52
Atlantic cod ranging in size from 151-740 mm TL were sampled from March-November (Table 19). Cod mature at approximately 650 mm TL (Bigelow and Schroeder 1953). According to this finding, 97% of the cod collected in the study area were juveniles. CPUE increased from 1971-1972 but declined con-tinuously during postoperational years to a low in 1978 (Table 20). From 1973-1978, there was an 80% decrease in CPUE reflecting declining abundance. How-ever, CPUE increased from 2.8 in 1978 to 6.5 in 1979. Alewives, ranging in size from 105-302 mm FL, were most abundant in the spring (Table 19). After examining abundance indices (Table 20) for this species, it is apparent that fluctuations in CPUE reflect natural variability. The majority of blueback herring (75-236 mm FL) were collected on one sampling day in late November (Table 19). Atlantic mackerel (240-448 mm FL) were most abundant in the spring and fall (Table 19). Tautog (186-479 mm TL) were captured in all seasons except winter and only in small numbers (Table 19). Largest catches of northern searobin were made in June. Bluefish (169-377 mm FL) were primarily collected in summer and early fall. Of note, one individual was captured in December (Table 19). Rainbow smelt (152-220 mm FL) were most abundant in the vicinity of PNPS in the winter months prior to commencement of the spawning-run into fresh water. However, the last six species were col-lected in insufficient numbers throughout the study to establish abundance trends. It is concluded that PNPS had no observed impact on pelagic and groundfish species examined in 1979. Population fluctuations apparently resulted from natural variability. I l 53
~
UNDERWATER FINTISH OBSERVATIONS The 1979 underwater finfish observational study commenced 24 April and continued through 17 October. Stations (Figure 6) and sampling techniques were identical to those previously reported by Lawton et g. (1978a). However, during this year's program, dissolved oxygen samples were to be collected only upon observation of numbers of distressed, moribund,or dead biota. Previous results indicated that dissolved oxygen concentrations (surface and bottom) were similar at all observational stations and comparable to data obtained from our weekly dissolved gas saturation analysis program. It should be stressed that reported size ranges of fish were estimated by visual observa-tions. Species analysis A total of seven finfish species (cunner, tautog, pollock, winter flounder, yellowtail flounder, longhorn sculpin and lumpfish) was observed during diving operations. Overall, surface and bottom water temperatures ranged from 8.0 to 29.0C and 12.2 to 19.0C, raspectively. Finfish were present in the study area during each of the ten dives, however, species composition varied spatially and temporally. Cunner (Tautogolabrus adspersus) Cunner were sighted at all stations during the study (Table 21) but not necessarily at every station on each dive (Table 22). Their presence was noted from 22 May through 2 October at bottom water temperatures ranging from 12.2 to 19.CC. Individuals ranged in size from approximately 2 to 25 cm total length (TL), but the majority were from 7 to 12 cm TL. [ 54
i !I
~ ,e g
j PNPS 478 _ 47 0
- m. ~ ,. ,
7,, ,,, I it ' W ' (~~2-Q h- A* MLw D4 e Di e D2 e
- D3 p d unEL I INTAKE STRUCTURE
\ \f OO I t u OO[L c, e
l:- W I'
; TURBINE BUILDING {{ ') si b LJ Jr I -
Figure 6. Finfish observational diving stations at PNPS.
~
I ~
~
lI .
I Table 21. Occurrence of finfish species at each observational station from 24 April through 17 October ,1979. I Species D1 D2 D3 D4 DS Tautogolabrus adspersus + + + + + (cunner) Pollachius virens + + + + + i (pollock) l Cyclopterus lumpus + (lumpfish) Pseudopleuronectes americanus + + + (winter flounder) Myoxocephalus octodeciespinosus + + (longhorn sculpin) Limanda ferruginea + + (yellowtail flounder) l W Tautoga onitis + + + + + (tautog) I l I I I I 56 \ t
m m m m m m m W W m m m m m M Table 22. Approximate numbers of finfish species that occurred at each observational station from 24 April through 17 October ,1979. Approximate total for all Station Apr 24 May 22 June 15 June 26 July 9 July 26 Aug 7 Sept 10 Oct 2 Oct 17 dates combined CUNNER D1 *
- 2 6 42 24
+ 6 6 0 86+
D2 0 0 50 18 6 45 67 0 22 0 208 D3 0 10 25 18 4 25 18 2 10 'O 112 D4
- 12 25 + 12 14 18 * *
- 81+
D5
- 0 + 8 10 4 * * *
+ 22+
m POLLOCK h D1-
- 30 20 0 O O O 7 7 0 64 D2 0 50 20 6 50 25 6 11 10 50 228 D3 0 0 6 2 40 20 0 0 6 50 124 D4
- 35 6 0 55 25 * *
- 2 123 D5
- O 40 + 75 12 2 * *
- 129t LUMPFISH D1
- 0 0 0 0 0 0 0 0 0 0 D2 0 0 0 0 0 0 0 0 0 0 0 D3 0 0 0 0 0 0 0 0 0 0 0 D4
- 0 0 0 0 0 0 * *
- O D5
- 1 0 0 0 0 0 * *
- 1 ,
Table 22. Approximate numbers of finfish species that occurred (cont.) at each observational station from 24 April through 17 October, 1979, Approximate total for all Station Apr 24 May 22 June 15 June 26 July 9 July 26 Aug 7 Sept 10 Oct 2 Oct 17 dates combined WINTER FLOUNDER D1
- O O O O O O O O O O D2 2 0 4 0 0 0 0 0 0 0 6 D3 0 0 0 0 0 0 0 0 0 0 0 D4
- 1 0 1 1 0 0 * *
- 3 D5
- O O O 2 0 0 * *
- 2 LONGilORN SCULPIN D1
- O O O O O O O O O O E
D2 0 0 0 0 0 0 0 0 0 0 0 D3 1 0 0 0 0 0 0 0 0 0 1 m
- 1 0 0 0 0 0 * *
- 1 DS
- 0 0 0 0 0 0 * *
- O YELLOWTAIL FLOUNDER D1
- 0 0 0 0 0 0 0 0 0 0 D2 0 0 0 0 3 0 0 0 0 0 3 D3 0 0 0 0 0 0 0 0 0 0 0 M
- 0 0 0 0 0 0 * *
- O D5
- 0 + 0 0 0 0 * * * +
m M M M M M M M W W W M M M M M M
M M M M M M M M M M M M M M M M Table 22. Approximate numbers of finfish species that occurre6 (cont,) at each observational station from 24 April throug'. 17 October ,1979. Appro'r.imate total for all Station Apr 24 May 22 June 15 June 26 July 9 July 26 Aug 7 Sept 10 Oct 2 Oct 17 dates combined TAUTOG D1
- 0 0 0 0 20 0 0 0 0 20 D2 0 0 0 0 4 0 0 15' 2 0 21 D3 0 0 0 0 0 0 0 0 1 0 1 D4
- O O 1 18 0 0 * *
- 19 D5
- 0 0 2 4 0 0 * *
- 6
- no observations made
+ species was noted but not enumerated
I Overall, greater concentrations of cunner were observed at Station D2 - 5 g the mouth c. ^:he discharge canal (Table 22). Generally, when observations were made at all five stations, more cunner uere observed at D2 than at any I other station. On 26 June, equal concentrations were observed at D2 and D3, and on 9 July, greater concentrations were sighted at Stations D4 and DS. However, these outer stations (C4 and D5) are also in direct line with the mouth of the discharge. On 10 September, a dead cunner (approximately 6 cm TL) was found at Station D2. It was believed to have passed through the PNPS screen wash system. l Pollock (Pollachius virens) I l Pollock were recorded from 22 May through 17 October (Table 22) at bottom i water temperatures ranging from 12.2 to 19.0C. This species occurred at all stations (Table 21), however, distribution and abundance by station varied temporally. Individuals ranged in si::e from approximately 5 to 36 cm TL. Generally, greater concentrations of pollock were observed at Station D2 (Table 22). On two occasions, greater concentrations were observed at Stations D4 and/or D5. I Winter flounder (Pseudopleuronectes americanus) Winter flounder were observed only at those stations directly in line with 1 the mouth of the discharge canal (D2, Du and DS) and only from 24 April through 9 July (Tables 21 and 22). Bottom water temperatures during this period ranged from 13.3 to 14.0C. Fish were approximately 5 to 36 cm TL. Few winter flounder l were observed during the study period, with the largest number occurring at Station D2. l I ee I
I The two flounder sighted at Station D2 on 24 April were stressed, possibly suffering from thermal shock. Both fish were lethargic and slow in tactile response. However, no external symptoms of gas bubble disease were apparent. The bottom water temperature at the time of observation was 13.3C. I Tauteg (Tautoga onitis) Tautog were recorded at all stations (Table 21), but their occurrence varied by station and date (Table 22). Bottom water temperatures ranged from 13.6 to 16.0C during the period this species was observed (26 June - 2 October). Fish ranged in si::e from approximately 13 to 61 cm TL. The largest total number of tautog (21) was observed at Station D2, whereas the largest number observed during any one dive was 20 at Station D1 on 26 July. One tautog, approximately 30 cm TL, was evidently stressed at Station D2 on 10 September. The bottom water temperature was 16.0C. This fish was lying on its' side wedged between two rocks and only moved when prodded. The cause was possibly thermally related. No external symptoms of gas bubble disease were noted. Longhorn scul,in (Myoxocephalus octodecenspinosus) Only two longhorn sculpin were recorded (Table 22). Both were approxi-mately 13 cm TL. One was observed on 24 April at. Station D3, and the other on 22 May at Station E4 (Table 22). Bottom water temperature was 13.3C on both dates. I Yellowtail flounder (Limanda ferruginea) 7 Yellowtail flounder were observed only during two observationa1 dives I ! l l 61
I (Table 22). Yellowtail were noted but not enumerated at Station D5 on 15 June. Three yellowtail were recorded at Station D2 on 9 July at a bottom water temp-erature of 14.0C. Ir.dividuals ranged in size from approximately 10 to 13 cm TL. Lumpfish (Cyclopterus lumpus) I Only one lumpfish (= 25 cm TL) was observed during observational dives (Table 22). It was sighted on 22 May at Station D5. Although a bottom water temperature was not recorded that day at Station DS, bottom water temperatures at Stations D2, D3 and D4 were all 13.3C. Conclusions Although estimating numbers of finfish through diving observations has limitations, a trend was nevertheless apparent from 1979 data. Greater con-centrations of most species (cunner, pollock, winter flounder and tautog) were generally sighted at Station D2 (mouth of the discharge canal). Cunner, pollock and winter flounder were generally observed in larger concentrations at Stations D4 and/or D5. These Stations (D2, D4 and DS) are in a direct north-northeasterly line extending from the mouth of the discharge canal. The plume maintains this direction for as far as a few hundred meters (several hundred feet) from the discharge mouth. The distance to the point of bottom detach-ment flue ates from approximately 3 m (10 ft) at high tide to 90 m (300 ft) at low tide (Adams and Stol:enbach 1976). Based on the numbers of finfish sighted in the path of the plume versus numbers sighted at the other two stations, 1979 observations suggest that several finfish species are attracted to the effluent emerging from the dis-l charge canal. Attraction may be a result of haat, current, food supply, or a I I 62 I
I
~
combination of these factors. Fish were often observed actively feeding in the effluent at Station D2. Some finfish fed on nondescript food particles that probably resulted from screen washes. Others fed on portions of fish bodies, also possibly originating from screen washes and/or bait lost by sportsfishermen while surf casting at the mouth of the discharge. Finfish may also be attracted to the area by the artificial current of the discharge plume. Further investigations may improve our understanding of this phenomenon. In summation, no finfish were observed to exhibit overt symptoms of gas bubble disease. However, we noted two lethargic winter flounder on 24 April and a dead cunner and lethargic tautog on 10 September. The two flounder and tautog were possibly adversely affected by the thermal effluent via heat shock. The cunner was believed to have passed through the PNPS screen wash system. It is noteworthy that these incidents all occurred at Station D2, the mouth of the discharge canal. GAS SATURATICNS Weekly dissolved gas measurements of intake and discharge waters at PNPS were resumed this year in March and continued through November. Week]; data are presented in Table 23 and Figures 7, 8 and 9 but are reported and dis-cussed below as monthly means. In the approach channel intake, ambient water temperature increased from 4.1C in March to a peak of 16.1C in August. Intake temperatures de-clined steadily thereafter to a low of 10.1C by November. Dissolved oxygen concentrations declined steadily from 11.1 ppm in March to 8.4 ppm in November. Total dissolved gas and nitrogen plus argon saturation values (Figures 7 and 8) were generally at or near equilibrium (100% saturation) throughout this period. ' I I e3 g
Table 23. Dissolved gas analyses at PNPS, March-November, 1979. P O S S P P 0 H0 2 S N tar 0 Date Sta. Time Tiden sat atmos Temp. 2 2 (sat. val.) tot 2 2 (mm Hg) (mm Hg) (80) (ppm) (mm Hg) (ppm) (%) (%) (%) 3/ 5 I 8:35 4:23 20.0 769.0 4.0 11.0 6.1010 10.70 D 8:50 101.8 101.5 102.8 4:38 170.0 769.0 15.0 10.3 12.7880 8.40 120.4 119.8 122.6 3/12 I 9:03 10:21 10.0 755.0 2.0 11.2 5.2940 11.30 100.6 101.0 99.1 D 9:14 10:32 197.0 755.0 16.0 10.9 13.6340' 3/21 I 13:40 10.90 124.3 122.0 132.9 9:20 22.;5 763.0 6.5 9.8 7.2590 10.10 102.0 103.3 97.0 D 14:10 9:50 232.5 763.0 20.5 10.0 18.0860 3/27 7.50 128.1 126.7 133.3 I 13:25 3:17 42,0 761.0 12.5 6.1010 4.0 10.70 104.7 101.5 116.9 D 13:45 3:37 72.0 761.0 3.5 12.9 6.3190 4/ 4 10.85 108.6 105.9 118.9 I 10:15 5:40 41.0 767.0 6.0 10.2 7.0130 10.20 104.4 105.6 100.0 D ,10:34 5:59 112.0 767.0 21.0 10.0 18.6500 7.50 112.2 106.5 133.3 4/11 I 11:07 0:39 28.0 765.0 5.4 10.8 6.7280 10.35 102.8 102.3 104.4 D 11:27 0:59 146.0 765.0 20.5 9.6 18.0860 4/17 9:57 7.50 147.7 113.7 128.0 I 7:48 45.0 757.5 5.5 11.3 6.7750 10.40 E ' D 10:15 8:06 105.1 104.1 108.6
., 190.0 757.0 20.5 10.0 18.0860 7.50 122.7 4/26 10:50 0:06 122.9 133.3 I 72.0 764.0 9.2 10.8 8.7270 9.50 108.3 106.8 D 11:15 0:31 224.0 764.0 113.7 23.0 10.7 21.0600 10.70 126.6 120.7 148.6 5/ 3 I 9':10 4:14 163.0 765.0 23.0 10.8 21.0680 9:35 7.20 118.6 110.2 150.0 D 4:39 137.0 765.0 20.0 10.3 17.5350 7.60 5/10 9:54 11:20 115.6 110.3 135.5 I 60.0 758.0 11.0 9.6 9.8440 9.10 106.6 D 10:10 11:30 222.5 106.9 105.5 758*0 25.5 9.6 ,,24.4715 6.90 .126.1 5/14 I 11:50 10:36 87.5 122.6 139.1 760.0 12.0 10.7 10.5180 8.90 110.r. 107.4 D 12:10 10:36 52.5 760.0 120.2 8.5 9.8 8.3240 9.80 105.8 106.8 102.1 5/23 I 10:50 1:04 35.0 764.0 14.5 8.8 12.3020 11:05 8.45 103.0 102.6 104.1 l D 1:19 40.0 764.0 12.5 , 9.1 10.8700 5/30 9:53 8.83 103.8 104.0 103.1 l I 7:12 42.5 760.0 12.5 9.0 10.8700 D 10:15 7:34 8.83 104.2 104.7- 101.9 115.0 760.0 19.5 8.8 17.0000 7.67 l 6/ 6 9:10 50.5 112.9 112.4 ' 114.7 I 0:20 758.0 14.5 9.0 12.3820 8.45 105.0 9:27 0:37 104.'6 106.5 D 185.0 759.0 28.0 8.6 20.3490 6.60 6/13 7:58 6:19 120.6 118.0 130.3 I 45.0 763.0 12.5 9.0 10.8700 8.85 D 8:20 6:41 180.0 104.5 105.1 101.9 763.0 28.5 8.7 29.1850 6.54 6/19 I 9:30 2:00 50.0 119.8 116.2 133.0 764.0 15.0 9.2 12.7880 8.47 104.9 D 9:40 2:10 120.0 103.8 108.6 764.0 25.0 8.2 23.7560 6.94 112.6 6/25 I 10:00 9:52 764.0 111.1 , 116.2 45.0 17.5 9.1 14.9880 7.96 103.9 101.1 D 10:16 10:08 165.0 764.5 31.5 114.3 0.0 34.6670 6.23 117.0 114.0 128.4 l_ -_ ___ ___ __ _
M M M M m M M M M M M m m m W W M M m Table 23. Dissolved gas analyses at PNPS, March-November, 1979. (cont.) P O S S P P O 11 0 2 S N + Ar 0 sat a tinos Temp. 2 2 (sat. val.) tot 2 2 Ddte Sta. Time Tide /* (mm !!g) (n.m lig) ( C) (ppm) (mm ifg ) (ppm) (%) (%) (%) 7/2/79 I 9:23 4:01 59.5 753.5 14.0 8.6 11.987 8.55 106.3 107.8 100.6 7/2/79 D 9:40 4:18 210.5 753.5 22.5 9.7 20.440 7.26 125.2 123.0 133.6 7/10/79 I 8:50 10:30 45.0 762.5 11.0 9.2 -9.844 9.10 104.6 105.5 101.1 7/10/79 D 9:05 10:45 150.0 763.0 22.5 8.8 20.440 7.26 117.0 115.8 121.2 ) 7/17/79 I 10:25 4:20 66.5 761.0 14.5 8.9 12.382 8.45 107.1 107.6 105.3 7/17/79 D 10:51 4:46 42.5 761.0 14.0 9.0 11.987 8.55 104.0 103.6 105.3 7/25/79 I 9:08 8:40 100.0 762.0 17.5 8.8 14.988 7.96 111.2 111.3 110.6 7/25/79 D 9:27 8:59 205.0 762.0 31.5 8.2 34.667 6.24 122.4 119.9 131.4 7/31/79 I 7:52 3:10 87.5 762.0 18.5 9.4 15.971 7.82 109.4 106.5 120.2 7/31/79 D 8:08 3:26 162.5 762.0 26.0 7.8 25.209 6.83 118.0 119.0 114.2 8/6/79 I 8:10 9:54 85.0 758.0 16.0 9.0 13.634 8.20 109.4 109.3 109.8 m 8/6/79 D 8:27 10:11 197.5 758.0 29.5 8.2 30.924 6.44 122.0 120.5 127.'3 8/14/79 I 10:25 5:44 87.5 758.0 17.0 9.1 14.530 8.03 109.6 108.6 113.3 8/14/79 D 10:42 6:01 140.0 758.0 31.0 7.3 33.695 6.29 114.0 113.5 116.1 8/22/79 I 8:10 8:10 27.0 762.0 16.5 7.8 14.077 8.13 101.8 103.3 95.9 8/22/79 D 8:28 8:28 175.0 762.0 31.0 7.4 53.695 6.30 118.4 118.8 117.5 8/28/79 I 8:52 5:26 125.0 761.5 15.0 9.1 12.788 8.37 115.1 116.7 108.7
. 8/28/79 D 9:13 5:47 4.0 761.0 18.0 7.6 15.477 7.88 98.5 99.0 96.5 9/6/79 I 8:45 9:10 40.0 756 s 17.0 7.4 14.530 8.04 103.4 106.4 92.0 9/6/79 D 9:00 9:25 170.0 750.0 27.0 8.1 26.739 6.70 119.0 118.4 120.9 9/11/79 I 9:30 6:07 30.0 761.0 11.0 8.8 9.844 9.11 102.6 104.2 96.6 9/11/79 D 9:45 6:22 155.0 761.0 25.0 8.0 23.756 6.94 117.2 117.7 115.3 9/20/79 I 8:42 .9:37 17.5 764.0 11.0 9.6 9.844 9.10 101.0 99.8 105.5 9/20/79 D 8:59 9:54 150.0 764.0 24.0 8.3 22.377 7.05 116.7 116.4 117.7 9/25/79 I 10:35 8:15 17.5 767.0 12.5 8.6 10.870 9.01 100.9 102.3 95.4 9/25/79 D 10:48 8:28 147.5 767.0 25.5 8.0 24.472 6.87 116.0 115.9 116.4 10/2/79 I 9:10 0:42 20.0 754.0 14.5 8.1 12.382 8.45 101.0 102.4 95.9 10/2/79 D 9:27 0:59 155.5 754.0 25.5 7.8 24.472 6.87 117.3 118.3 113.5 10/9/79 I 11:20 9:09 17.0 750.0 12.0 8.4 10.518 8.90 100.9 102.6 94.4
Table 23. Dissolved gas analyses at PNPS, March-November,1979. (cont.) P O S S P P O !! 0 2 S N tar 0 sat atmos Temp. 2 2 (sat. val.) tot 2 2 Date Sta. Time Tide l- (mm Hg ) (mm lig) (oC) (ppm) (mm lig ) (ppm) (%) (t) (%) 10/9/79 D 11:37 155.0 750.0 24.0 7.5 22.377 7.06 117.7 120.7 106.2 10/15/79 I 1:25 5.0 760.0 11.5 8.6 10.177 9.00 99.3 100.3 95.6 10/15/79 D 1:42 140.0 759.5 24.5 8.4 23.284 7.00 115.4 114.1 120.0 10/25/79 I 10:40 15.0 753.5 12.5 8.0 10.870 8.83 100.6 103.2 90.6 10/25/79 D 10:56 155.0 754.0 27.5 7.3 27.535 6.65 116.9 118.8 109.8 10/29/79 I 10:20 25.0 758.0 12.0 9.2 10.518 8.90 101.9 101.5 103.4 10/29/79 D 10:35 150.0 758.0 27.5 8.4 27.535 6.64 116.2 113.4 126.5 11/7/79 I 8:33 7.5 761.0 11.0 8.7 9.844 9.12 99.7 100.8 95.4 11/7/79 D 8:45 142.5 761.0 26.5 8.2 25.965 6.76 115.3 113.7 121.3 11/15/79 I 8:37 5.0 762.0 10.5 8.9 9.522 9.21 99.4 100.1 96.6 11/15/79 D 8:45 110.0 762.0 20.0 8.2 17.535 7.60 112.1 113.2 107.9 11/23/79 I 8:55 5.0 765.0 10.5 7.6 9.522 9.21 98.1 102.2 82.5 11/23/79 D 9:10 152.5 765.0 25.0 8.1 23.756 6.94 116.8 116.8 116.7 y, 11/30/79 I 9:12 15.0 758.0 8.5 8.5 8.324 9.63 96.9 99.2 88.3 11/30/79 D 9:23 155.0 758.0 24.5 8.2 23.060 7.00 117.4 117.4 117.1
- Designates hours and minutes after high tide.
m ae m e m M M M M M M W M M M M M M
m M M M m M M M m m M mM M M M M M m figure 7. Monthly . ranges and mean saturation values of total dissolved gas (Stot), PNPS, March-November,1979. 140 INTAKE - DISCHARGE W. -E
~~ "
, 120 - . a __ x. N ' ['[M< 3 -
# ~~
100- -- - ee a 9 80- - l g g MAR APR M AY JUN JUL AUG SEP OCT NOV MAR A PR MAY JUN JUL AUG SEP OCT NOV
l'igure 8. Monthly ranges and mean saturation values of dissolved nitrogen plus argon (SII *gp), 2 P!IPS, March-riovember, 1979. 14 0 !NTAKE - D I S C H ARG E
'" ~~
120- ~ g ., .. T l
/ .. ~~ ~~ ~ '
! 100 , ' 1 -- . l x i 80- , s 8 I e s a a i i M AR APR M AY JUN JUL AUG SEP OCT y e i s s : NOV MAR APR M AY JUN JUL AUG SEP OCT s NOV W _ - - - _ - _ _ W M M _ M - - - _ M __ M _ _ _ _ _ M M M M M M M M M M W W
- : , ' 1l l
- - a V - - O M N T
e - e C W - O M P i E S M E G G . - U R m - A M A H C S I D
\. .
i L U J M N d i U _ e J _ v _ l o Y s A M i s ,
~
M d f _ o R -
. i P M s .
e9 A u7 l9 a1 R v 1 A M nr oe M ib t m ae rv _ - - - - M uo tN a-sh V c O nr aa N _ M eM m, T dS _ nP _ , iC _ aN O P M s e , g) P n 2 i E aO S rS ( M y l n h e . . G e U t g . ny A ox Mo E M K A i L U
. J T
9 N e N M r g u I
- U J
i F Y
- A M _ - i M
R s P M A
/ .
i R A M M 0 o o o M 4
; 2, c i
B
$x M
I 0xygen saturations (Figure 9) averaged less than 100% except in May (116%). Average discharge water temperatures increased steadily (excei,t during a May outage) from 13.8C in March to 28.2C in June. Temperatures thereafter fluctuated with another high (27.4C) occurring in Aug2st. Total dissolved gas and oxygen sa:%=sions (i* p es 7 and 9) were higtest in April (S = 127% and S 0
= 136%). Nitrogen plus argon saturatior. (Figure 8) was highest 2
in March (119%). Condit'.ons in the discharge canal approached ambient during the aforement oned twe- week plant outage in May (Table 23; Figure 7, e and 9). Percent distributions of intake and discharge saturation levels for dis-solved gases are presented in Table 24 Although supersaturated conditions generally prevailed in discharge waters, no incidents of gas bubble disease j were recorded in fish collected and observed in the environs of PNPS. On 3 May and 28 August, during backwash procedures at PNPS, values for intake parameters exceeded those in the discharge. On 3 May, intake water temperature increased form 16.0 to 23.0C in less than one hour. Oxygen satura-tion was determined to be 150%, which is the highest value recorded in the in-take during the entire study. Four cunner were noted floating on the water's surface in the intake embayment, circumstantially having died from the pre-cipitous rise in temperature. On 28 August, four dead crabs were observed in the intake canal, pre-I sumauly hr.ving died during the backwash. Simultaneously, a dead lobster was l observed in the discharge canal. It was assumed to have been impinged and removed from intake screens during routine washing procedures. In July, approximately 75 dead short-finned squid (Illex illecebrosus) and an undetermined number of mutilated silverside s (Menidia spp. ) were ob-I I 70 I
M M M M M M M M M M M M M M M M M M M Table 24. Percent distribution of saturation levels of total dissolved gas, nitrogen plus argon, and oxygen at PflPS, March-liovember, 1979 PERCENT DISTRIBUTIONS Saturation Total gas Nitrogen + turgon Oxygen levels (%) Intake Discharge IntaEe Discharge Intake Discharge
< 100 12.8 2.6 5.1 2.6
- 35.9 2.6 100-105 53.8 2.6 56.4 2.6 23.1 0.0 105-110 23.1 7.7 30.8 10.3 20.5 15.4 110-115 5.1 12.8 5.1 25.6 10.3 7.7
> 115 5.1 74.4 2.6 59.0 10.3 74.4 4 =
H Total number of samples = 39 .l
I served on the beach within the PNPS intake embayment. No backwash procedure was underway at that time, and ambient water temperature was 11.0C. Total gas, oxygen, and nitrogen plus argon saturations were near equi:ibrium (100%). Numere ts cases of stranded squid were documented during the previous month (11-15 June) at various locations on the north and south side of Cape Cod. Beached squid were also reported in the Manomet area during June (Kolek pers. commun.)l. It was speculated that squid became stranded in the shoals while chasing bait during moon tides. Predators, such as bluefish, cod or striped bass, may also have been responsible for driving the squid inshore (Amaral pers. commun.)2, Other species, including young-of-the-year pollock (Pollachius virens), l small sand lance ( Ammodytes spp. ) and mummichogs (Fundulus spp. ) were observed beached at various locations. Individuals of these species were frequently observed to be mutilated possibly,resulting from predation by squid and/or larger rapacious finfish (Lange and Amaral 1979). l The squid incident in the PNPS intake embayment occurred within a mcnth of the initial strandings and also during a moon tide. The discovery of mutilated silversides indicated possible precation by squid or larger finfish. 1 Based on available evidence, the squid and silversides noted in the intake em-bayment on 10 July probably died from natural causes unrelated to plant impact. I 1A . Kolek, Mass. Division of Marine Fisheries, 10 !eritage Professional Building, Rte 6A, Sandwich, Massachusetts 02563. 2E . Amaral, Mass. Divisio: of Marine Fisheries,18 Heritage Professional Builling, Rte 6A, Sandwich, Massachusetts 02563. I
~
I 22 I
I
~
SUMMARY
A total of 2,820 lobster pots was sampled in 1979. Overall catch rate (pooled legal and sublegal data) was 2.0 (mean catch per haul), the lowest for the entire study. Reduction in overall catch rates this year may reflect a declining population and/or increased harvesting pressure. During 1979, rakers expended 1,337.7 hrs and harvested 227,293 lbs (wet weight) of Irish moss from the study area at a mean rate of 169.9 lbs/hr. Harvesting parameters for pooled area data declined slightly from that of 1978. Harvest rates for Area 1 (control) and Area 5 (surveillance) approached pre-operational levels. Landings in both areas decreased approximately 50%, and effort declined 49.3% and 65.8%, respectively. Hewever, similarity in temporal production and an increase in harvest rate of 26.6% from 1978 in Area 5 indi-care that PNPS operation had no adverse effect on the local Irish moss harvest. Two stations (4 and 5) were added to the otter trawl survey this year. A total of 8,126 fish comprising 27 species was collected in 111 tows. The dominance pattern was idantical, and percent catch co:rposition was similar to that in 1977 and 1978. However, mean annual CPUE of all species combined for pooled stations increased substantially from 37.0 in 1977 and 27.0 in 1973 to 73.2 in 1979. Mean CPUE (pooled stations' data) for individual dominant species increased censiderably (winter flounder - 67%, skate spp. - 167%, yelloutail flounder - 65%, and windowpane - 208%) from 1978. No adverse PNPS effect is evident from the analyses of groundfish data. In late August, two panels of larger mesh si::es were added to our experi-mental gill net in order to reduce gear selectivity. A total of 4,418 fish comprising 26 species was collected in 19 sets of the net. An additional 78 fish were caught in the two larger mesh panels. Mean CPUE for all species I I
I 1 I combined increased 15% to a value of 232.5 for 1979. Examination of abundance indices for pollock indicate fluctuations reflecting natural population vari-ability. Mean CPUE for Atlantic herring has fluctuated throughout the study, I this year increasing 60.2% from that of 1978. Although mean CPUE for cunner declined 12.3% from last year, it is double the value of abundance for pre-operational years (1971-1972). CPUE for Atlantic menhaden was the highest recorded la the entire study. Atlantic cod CPUE continuously decreased during postoperi.tional years to a low in 1978, however CPUI in 1979 increased 56.9% over laat year, Annual abundance estimtes of alewives apparently reflect natural populaticn fluctuations. PNPS had no observed impact on finfish species examined in 1979, atd population fluctuations apparently resulted from natural variability. In 1979, a total of seven finfish species was observed in ten observational dives. Species composition varied spatially and temporally. No finfish were observed to exhibit overt symptoms of GBD. However, at Station D2 (discharge canal) two winter flounder 3nd one tautog were observed to be lethargic, E possibly suffering from thermal shock. Also at Station D2, one dead cunner was sighted, presumably having passed through the PNPS screen wash system. Generally, greater concentrations of most species were sighted in the path of the plume. These observations suggest that several finfish species are attracted to PNPS discharge water. Weekly dissolved gas measurements of intake and discharge waters at PNPS were recorded frem March to November. Intake canal saturation parameters generally were at or near equilibrim (100% saturation). Exceptions occurred on 3 May and 28 August, during routine backwash procedures, when intake para-meters exceeded those in the discharge. Most noteworthy, on 3 May, oxygen I I
I saturation was determined to be 150% in the intake. Supersaturated conditions generally prevailed in discharge waters except during a May outage when gas saturation values approached ambient. GBD was not noted in fish collected and observed in off-site wate:s during 1979. However, dead cunner (4) and ccchs (4) were observed in the intake channel. Death presumably resulted from FNPS backwash procedures. One dead lobster was sighted in the discharge canal, supposedly having been impinged and removed from intake screens during routine washing. Approximately 75 dead squid and an undetermined number of mutilated silversides were observed within the PNPS intake embayment. It is believed that death resulted from natural causes, unrelated to plant impac.L. I I I I I I I I , I l l
I-ACKNOWLEDGEMENTS We acknowledge the contributions of Susan Faria, Cathy Chabot, Lawrence rurrer, Steven Correia, and Sandra Beaton of the Massachusetts Division of l'arine Fisheries for phases of field sampling and data synthesis, including: compilation, computations, programming, and tabulation. We also extend special thanks to Miss Faria for preparation of preliminary drafts of several report subsections and together with Mr. Furrer for reviewing the final manu-script. We extend much appreciation to Eleanor Bois and Marie Callahan who worked so diligently to type the report. I I I I I I I: I , I g. Il
- I
I LITEPATURE CITED Adams, E.E., and K.D. Stol:enbach. 1975. Analytical studies of the Pilgrim I Nuclear Power Station thermal plume. In: Marine Ecology Studies Related to Operation of Pilgrim Station. Semi-Annual Report No. 7. Company, Boston, Mass. Boston Edison American Fisheries Society. 1970. A List of Common and Scientific Names of Fishes from the United States and Canada. Special Pub. No. 6. Third Edition. Bigelow, H.B., and W.C. Schroeder. 1953. Fishes of the Gulf of Maine. Fish. Bull. Fish Wildl. Ser. 53(74): 577p. Lange, A.M.T., and E. Amaral. 1979. Strandings of Short-Finned Squid on Cape Cod, Massachusetts. Coastal Oceanography and Climatology News. 1(4): 42. I Lawton, R.P., E. Keuloheras, W. Sides, and M. Borgatti. 1978a. Progress report on studies to evaluate possible effects of Pilgrim Nuclear Power Station on the marine environment. Project Report No. 25. In: Marine Ecology I Studies Related to Operation of Pilgrim Station.
- 12. Boston Edison Company, Boston, Mass.
Semi-Annual Report No.
, J. Wennemer, and 1978b. Progress report on studies I
to evaluate possible effects of Pilgrim Nuclear Power Station on the marine environment. Project Report No. 26. In: Marine Ecology Studies Related to Operation of Pilgrim Station. Semi-Annual Report No. 13. Boston Edison Company, Boston, Mass. Massachusetts Division of Marine Fisheries. 1973. Progress report upon studies to evaluate possible eff iets of the Pilgrim Steam Generating I Station upon the marine envirorssnt. Report No. 15. In: Marine Ecology Studies Related to Operxtion of Pilgrim Station. Report No. 3. Boston Edison Company, Boston, Mass. Summary Steele, D.H. 1963. Pollock (Pollachius virens L.) in the Bay of Fundy. J. Fish. Res. Bd. Canada. 20(5): 1267-1314 I I I I il I I " l
____l l I Jm 1gi i i lI i i II I lI j i lI d i I il : AFPENDIX P
- E Sumary of Lobster Pot Catch Data by Quadrat - 1979 J
I iI , 1
- I I
I lI i I lIi I I ^-1
Ratio
\
Mean Mean
# cf S am- # of Total Sub- Legals Catch Sub-niinq n,yn Pots Catch Male Female Legals legals Eggers / Pot / Pot Legals : legals : Eggers D-14 2 19 54 28 26 9 45 0 0.5 3.0 1.0 5.0 0.0 E-13 1 8 13 10 3 4 9 0 0.5 1.6 1.0 2.3 0.0 , E-14 4 37 100 56 44 17 83 0 0.5 2.7 1.0 4.9 0.0 I
E-15 1 12 25 10 15 5 20 0 0.4 2.1 1.0 4.0 0.0 F-10 3 21 77 33 44 .15 58 4 0.7 3.7 1.0 3.9 0.3 O
M M M M M W4 M M M M M M M M M M M M M Ratio Mean Mean
# of Sam- # of Total Sub- Legals catch Sub-plinF Days Pots Catch Male Female Legals legals Eggers /Por / Pot Legals : legals : Eggers F-11 3 7 18 7 11 3 15 0 0.4 2.6 1.0 5.0 0.0 F-12 3 11 15 9 6 3 12 0 0.3 1.4 1.0 4.0 0.0 l b F-13 2 11 21 11 10 7 14 0 0.6 1.9 1.0 2.0 0.0 P-14 7 88 251 132 119 51 200 0 0.6 2.9 1.0 3.9 0.0 F-15 l
7 50 100 59 41 27 72 1 0.5 2.0 1.0 2.7 0.0 t
l ( Ratio Mean Mean
# of Sam- # of Total Sub- Legals Catch Sub-pline Davs Pots Catch Male remale Legals legals Eggers / Pot / Pot Legals : legals : Eggers 1
- G-10 10 89 195 75 120 34 161 0 0.4 2.2 1.0 4.7 0.0 i
G-11 10 170 485 203 277 96 386 3 0.6 2.9 1.0 4.0 0.0 i l G-12 Y
& 8 56 121 59 62 21 100 0 0.4 2.2 1.0 4.8 0.0 G-13 4 33 68 33 35 13 55 0 0.4 2.1 1.0 4.2 0.0 G-14 6 60 141 74 67 22 119 0 0.4 2.4 1.0 5.4 0.0 M M M M M M M M M M M M M M M M M M M
m m m m e M m m m m m m m m m a e a e Ratio - Mean Mean
# of Sam- # of Total Sub- Legals Catch Sub-plinri Days Pots catch Male l'emale Legals legals Eggers / Pot / Pot Legals : legals : Eggers G-15 1 4 10 7 3 3 6 1 0.8 2.5 1.0 2.0 0.3 11 - 1 0 7 66 164 59 105 33 131 0 0.5 2.5 1.0 4.0 0.0 T
11 - 1 1 10 202 535 235 300 85 443 7 0.4 2.6 1.0 5.2 0.1 11 - 1 2 5 48 86 37 49 16 70 0 0.3 1.8 1.0
- 4.4 0.0 I-9 1 1 1 0 1 0 1 0 0.0 1.0 0.0 0.0 0.0 c .s o
Ratio Mean Haan
# of Sam- # of Total Sub- Legals Catch Sub-niing navs Pots Catch Male remale Legals legals Eggers / Pot / Pot Legals : legals : Eggers I-10 2 14 38 17 21 3 35 0 0.2 2.7 1.0 11.7 0.0 I-11 9 53 128 67 61 27 101 0 0.5 2.4 1.0 3.7 0.0 & I-12 4 23 43 28 15 17 26 0 0.7 1.9 1.0 1.5 0.0 J-10 ,
l 1 3 8 3 5 2 6 0 0.7 2.7 1.0 3.0 0.0 J-11 2 8 23 14 9 6 17 0 0.8 2.9 1.0 2.8 0.0 c
Nq q q q q g g g g g g g g g g g g g g Ratio Mean Mean
# of S am- # of Total Sub- Legals Catch Sub-l pling Days Pots Catch Male Female Legals legals Eggers / Pot / Pot Legals : legals : Eggers J-12 2 2 7 4 3 2 5 0 1.0 3.5 1.0 2.5 0.0 l
l ' l L-8 1 8 17 5 12 7 10 0 0.9 2.1 1.0 1.4 0.0 , T a L-10 2 30 48 13 35 9 39 0 0.3 1.6 1.0 4.3 0.0 M-7 1 16 24 - 10 14 6 18 0 0.4 1.5 1.0 3.0 0.0 M-8 1 40 49 12 37 7 42 0 0.2 1.2 1.0 6.0 0.0 c l o
Ratio Mean Mean
# cf C am- # (,i Total Sub- Legals Catch Sub-pline Days Pots Catch Male Female Legals legals Eggers /Por / Pot Legals : legals : Eggers
[ M--9 l l 2 12 26 5 21 10 16 0 0.8 2.2 1.0 1.6 0.0 M-10 4 43 78 23 55 19 58 1 0.6 2.4 1.0 3.1 0.1 M-11 2 11 12 5 7 3 9 0 0.3 1.1 1.0 3.0 0.0 11 - 7 1 16 24 13 11 6 18 0 0.4 1.5 1.0 3.0 0.0 11 - 8 1 40 69 25 44 17 52 0 0.4 1.7 1.0 3.1 0.0 s
E E M M M M g g g g g Ratio ' Mean Mean -
# of Sam- # of Total Sub- Legals Catch Sub-piirur Days Pots Catch Male Female Legals legals Eggers /Por / Pot Legals : legals : Eggers N-9 3 40 73 26 47 33 40 0 1.1 2.4 1.0 1,2 o,o N-10 6 97 160 57 103 66 91 3 0.7 1.6 1.0 1.4 0.0 b N-11 5 95 158 52 106 54 99 5 0.6 1.7 1.0 1.8 0.1 N-12 2 7 15 6 9 3 11 1 0.4 2.1 1.0 3.7 0.3 O-9 2 32 63 22 41 27 36 0 0.8 2.0 1.0 1.3 0.0 G
Ratio Mean Mean *
# of Sam- # of Total Sub- Legals Catch Sub-pling Days Pots Catch Male Femate Legals legals Eggers /Por / Pot Legals : legals : Eggers . 0-10 5 85 146 53 93 48 95 3 0.6 1.7 1.0 2.0 0.1 0-11 6 138 210 73 137 66 142 2 0.5 1.5 1.0 2.3 0.0 7
y 0-12
. 6 4 79 103 35 68 28 73 2 0.4 1.3 1.0 2.0 0.1 0-13 1 2 4 1 3 0 4 0 0.0 2.0 0.0 0.0 0.0 P-9 3 37 50 17 33 10 40 0 0.3 1.4 1.0 4.0 0' . 0 c ?
o
Ratio Mean Mean
# of Sam- # of Total Sub- Legals Catch Sub-pling Days Pots catch Male Female Legals legals Eggers / Pot / Pot Legals , legals : Eggers P-10 t
3 38 62 18 44 17 43 2 0.4 1.6 1.0 2.5 0.0 P-11 4 38 49 19 30 15 34 0 0.4 1.3 1.0 2.3 0.0 E. P-12 H 4 79 125 61 64 33 90 2 0.4 1.6 1.0 2.7 0.1 P-13 3 54 76 30 46 21 54 1 0.4 1.4 l'. 0 2.6 0.0 P-14 2 .7 8 4 4 1 7 0 0.1 1.1 1.0 7.0 0.0 ., c ? 0
l __ _ _ _ _ _ _ - _ _ _ _ _ _ _ __ Ratio Mean Mean
# cf S am- # of Total Sub- Legals Catch Sub-I pline Days Pots Catch Male Female Legals legals Eggers /Por / Pot Legals : legals : Eggers Q-9 1 35 53 22 31 15 37 1 04 1.5 1.0 2.5 0.1 l
Q-10 1 20 46 12 34 13 32 1 0.7 2.3 1.0 2.5 0.1 7 Q-11 0 3 17 23 10 13 1 22 0 0.1 1.4 1.0 22.0 0.0 Q-12 4 2 18 16 5 11 2 13 1 0.1 0.9 1.0 6.5 0.5 Q-13 3 46 52 23 29 19 33 0 0.4 1.1 1.0 1.7 0.0
- ~
M M M M M M YT M M M M M M M M M Ratio Mean Mean
# of Sam- # of Total Sub- Legals Catch Sub-pling Days Pots Catch Male Female Legals legals Eggers /Por / Pot Legals : legals : Eggers Q-14 2 19 29 17 12 10 18 1 0.5 1.5 1.0 1.8 '1 R-10 2 11 30 7 23 6 23 1 0.5 2.7 1.0 3.8 0.2 b R-11 w
2 4 9 3 6 2 7 0 0.5 2.3 1.0 3.5 0.0 i R-13 3 57 85 31 54 22 61 2 0.4 1.5 1.0 , 2.8 0.1 R-14 2 28 35 21 14 9 25 1 0.3 1.3 1.0 2.8 0.1 l s 0
Ratio Mean Mean *
# of Sam- # of Total Sub- Legals Catch Sub-pling Days Pots Catch Hale Female Legals legals Eggers /Por / Pot Legals : legals : Eggers S-10 1 o 34 12 22 9 25 0 1.1 4.3 1.0 2.8 0.0 S-11 2 40 147 54 93 25 122 0 06 3.7 1.0 4.9 0.0 ?
7 S-12 1 10 16 8 8 5 11 0 0.5 16 1.0 2.2 0.0 S-13 2 3 2 0 2 0 2 0 0.0 0.7 0.0 0.0 0.0 S-15 1 2 4 3 1 1 3 0 0.5 2.0 1.0 3.0 0.0 is 9
Ratio Mean Mean -
# of Sam- # of Total Sub- Legals Catch Sub-
_pling Days Pots Catch Male Female Legals legals Eggers /Por / Pot Legals : legals : Eggers T-11 1 8 39 12 27 9 30 0 1.1 4.9 1.0 3.3 0.0 T-12 1 24 75 35 40 16 58 1 0.7 3.1 1.0 3.6 0.1 Y e Coles Hole 7 244 408 158 250 95 306 7 1.7 0.4 1.0 3.2 0.1 Ponces Ledge 2 86 117 46 71 39 75 3 0.5 1.4 1.0 2.0 0.1 2820 5596 2339 3257 1325 4214 57 0.5 2.0 1.0 3.2 0.0 t
=g i
2 m in
=
8 M C
.C.
4
I I BENTHIC STUDIES l l IN THE VICINITY OF PILGRIM STATION l I Report No. 15 September, 1979 - December, 1979 I l Prepared by TAXON, INC. 50 Grove Street Salem, Ma. 01970
I TABLE OF CONTENTS I Page I List of Tables vi List of Figures viii List of Appendices x
- 1. EXECUTIVE
SUMMARY
l 1.1 No Effects of PNPS 2 1.2 Effects Possibly Due to PNPS 3 1.3 lffects Definitely Due to PNPS 4
- 2. IN7 RODUCTION 6
- 3. MI.THODS 7 3 . '. Sampling Stations 7 3.2 Sampling Methods 9 3.2.1 Faunal Studies 9 3.2.2 Algal Studies 12 3.3 Statistical Analyses 14
- 4. FAUNA 15 4.1 I 4.2 Faunal Systematics Faunal Community Descriptions 15 16 4.2.1 Rock Stations 16 4.2.2 Sand Stations 17 4.3 Faunal Community Structure 18 4.3.1 Faunal Species Richness 18 4.3.2 Faunal Population Densities 21 4.3.3 Densities of Individual Faunal Species 27 4.4 Faunal Species Dominance 31 4.5 Faunal Community Overlap 34 4.6 Faunal Diversity 37 4.7 Classification Analysis 42 4.8 Ordination Analysis 44 1 1
4.9 Sediment Analysis 49 l 111
TABLE OF CONTENTS (continued) Page 1
- 5. ALGAE 53 i 5.1 Algal Systematics 53 5.2 Algal Comunity Descriptions 53 5.3 Algal Comunity Overlap 53 5.4 Algal Biomass Studies 55 5.4.1 Total Algal Biomass 56 5.4.2 Chondrus crispus Biomass 58 5.4.3 Phyllophora Biomass 60 5.4.4 Biomass of Epiphytic Species 61 5.4.5 Biomass of Remaining Benthic Species 62 5.4.6 chondrus/Phyllophora Condition Index Study 68 5.5 Laminaria Survey 68 5.5.1 Laminaria Population Density 68 5.5.2 Laminaria Species Density 69 5.5.3 Laminaria Blade Length 71 5.5.4 Laminaria Reproductivity 74 5.6 Ascophyllum nodosum Growth Study 75
- 6.
SUMMARY
76 6.1 Faunal Sumary 76 6.1.1 Faunal Systematics 76 6.1.2 Faunal Community Descriptions 76 6.1.3 Faunal Community Structure 77 6.1.4 Faunal Species Dominance 78 6.1.5 Faunal Community Overlap 78 6.1.6 Faunal Diversity 79 6.1.7 Classification Analysis 79 6.1.8 Ordination Analysis 80 l 6.1.9 Sediment Analysis 80 6.2 Algal Sumary 81 6.2.1 Algal Systematics 81 6.2.2 Algal Community Descriptions 81 iv 11
I I TABLE OF CONTENTS (continued) I Page I 6.2.3 Algal Community Overlap 81 6.2.4 I 6.2.5 Algal Biomass Studies Laminarla Survey 81 84 6.2.6 Ascophyllum nodosum Grouth Study 85 lI LITERATURE CITED 86 APPENDICES 88 I lI
'I i
.I
]
I I l i V -I , 1
LIST OF TABLES Table Page
- 1. Faunal species richness, densities of individuals including and excluding Modiolus modiolus/m2, and densities of Nodiolus modiolus/m2 during the period g December, 1978 through December, 1979. 19 E
- 2. Paired-difference test comparing faunal data for the g periods December, 1978 through December, 1979 and September, 1974 through December, 1979. Tests 5 compare species richness, numbers of individuals /m2 including and excluding Modiolus modiolus, community overlap, Shannon-Wiener diversity calculated including and excluding Modlolus, evenness, and numbers of Nodiolus modiolus/m2 . 20
- 3. Densities (numbers of individuals /m2) of ten dominant faunal species for September, 1979 and December, 1979. 28
- 4. Paired-difference tests comparing densities of ten j dominant faunal species during the periods December, 1978 through December, 1979 and September, 1976 through December, 1979. 29 l
- 5. Numerical dominance of faunal species found at rock and E sand stations during September, 1979. 32 3
- 6. Numerical dominance of faunal species found at rock and sand stations during December, 1979. 33
- 7. Faunal conmunity overlap between stations for the period December, 1978 through December, 1979. 35
- 8. Faunal community overlap between replicates of stations for the period December, 1978 through December, 1979. 35
- 9. Community overlap between stations comparing September 1978 with September, 1979 and December, 1978 with g December, 1979. 35 g i 10. Information theory diversity values for faunal studies.
l Values based on combined data for the periods September l l and December, 1979. 38 m 1 11. Information theory diversity values computed excluding g Modiolus modiolus for faunal studies. Values based on 5 l combined data for the periods September and December, l 1979. 41
- 12. Percent compostiion of sand substrate for the effluent 20' (MLW) sand station during September and December, 1979. 50 vi I
I LIST OF TABLES (continued) Tables Page
- 13. Community overlap (Jaccard's coefficient of community)
, for quantitative algal studies. Overlap between I replicates taken at the same station and overlap between stations is presented for September, 1979 and December, 1979, 54
- 14. Dry weight values (g/m2) for chondrus crispus, Phyllophora spp., remaining benthic species, epiphytes of Chondrus, epiphytes of Phyllophora, total epiphytic
'I biomass, and total algal biomass from the ten foot quantitative stations for the September, 1979 and December, 1979 collecting periods. 57
- 15. Colonization Values for chondrus crispus and Phyllophora spp. from the ten foot quantitative stations for the September, 1979 and December, 1979 collecting periods. 66
- 16. Condition Index Values for Chondrus crispus and I Phyllophora spp. from the ten foot quantitative stations for the September, 1979 and December, 1979 collecting periods. 67
- 17. Summary of data generated by the Laminaria survey of January, 1980 70
- 18. Results of one way ANOVA comparisons of blade length for Laminaria saccharina and L. digitata from the January, 1979 survey. 73
'I I
I I I I vii I
l LIST OF FIGURES Figure Page
- 1. Location of transects for benthic sampling in the g vicinity of Pilgrim Nuclear Power Station 8 5
- 2. Rock substratum airlift sampling device. 10
- 3. Sand substratum sampling device. 11
- 4. Total numbers of faunal species found at rock and sand stations for the period December, 1978 d through December, 1979. 22
- 5. Faunal densities per square meter at rock and sand stations. 23
- 6. Densities of Modlolus modiolus per square meter at 10' (MLW) rock stations. 25
- 7. Faunal densities excluding Nodlolus modlolus per l square meter at 10' (MLW) stations. 26 =
- 8. Faunal diversity (Shannon-Wiener) at rock and sand stations. 39
- 9. Dendrogram of similarity for faunal replicate stations. 43
- 10. Scattergram of faunal principal components analysis for the period September and Dece~ber, 1979; Factor 1 vs Factor 2. 46
- 11. Scattergram of faunal principal components analysis g for the period September and December, 1979; E Factor 1 vs Factor 3. 47
- 12. Scattergram of faunal principal components analysis for the period Se7tember and December, 1979; Factor 2 vs Factor 3. 48
- 13. Cumulative percent grain size of sand substrate at the effluent 20' ( L ) sand site during September and December, 1979. 51
- 14. Dry weight values (g/m ) for Chondrus crispus, Phyllophora spp., and the remaining benthic g.
species from the ten foot quantitative stations for the September, 1979 and December, 1979 5 collecting periods. 59 viii I I
I LIST OF FIGURES (continued) I Figure Page
- 15. Dry weight values (g/m ) for epiphytes of Chondrus epiphytes of Phyllophora, and total algal biomass I from the ten foot quantitative stations for the September, 1979 and December, 1979 collecting periods. 63 l 16. Size classes of Laminaria saccharina and lE . dl7 1tata blade length from January, 1980 survey. 72
'E I I I I I l I
;I I
I lI ix I
1 Il l LIST OF APPENDICES I Appendix Page
- 1. Faunal species list (numbers per square meter) 1 for September, 1979. 88 l
- 2. Faunal species list (numbers per square meter) g for December, 1979. 102 3
- 3. Algal species recorded from the ten foot quantitative stations for the September and December, 1979 collecting periods. The relative E 3
abundance of each species in each replicate sample is indicated. 116 g' Bl I I I I I l l El 1 I I I x I l
I I 1. EXECUTIVE
SUMMARY
This report summarizes benthic studies designed to continue monitoring the effects of thermal loading by Pilgrim Nuclear Power Station (?NPS) on marine benthos. Results of current faunal and algal I studies (September and December, 1979) are analyzed, compared to
- previous results, and interpreted with respect to possible impact by the thermal discharge. Where possible, a community approach has been used which allows estimation of community parameters such as species richness, densities of faunal components, and diversity. Statistical techniques allow evaluation of similarity and community overlap between sites which might be affected and control areas. Specific representative species are also monitored, although with less precision. Since the I value of such species as indicators of stress is often questionable, this approach is a limited part of the total study.
The marine environment surrounding PNPS consists of two major I substrate types, rock and sand. Rock areas dominate the intertidal zone and much of the shallow subtidal close to the discharge. In deeper water ( >30') and to the north and south of PNPS, rock gives way to sand. Control sites were chosen to resemble experimental areas which are in or close to the thermal effluent. However, no two sites are ever identical; there are always some differences in sediment type and exposure which can affect community characteristics. The marine environment at shallow subtidal depths is extremely patchy, particularly Even I at our sand area, resulting in significant subsample variability. so, samples from different sites displayed a high degree of overlap in faunal and floral species composition, often chowing as much similarity as replicate samples from one station. The fauna and flora found in the PNPS area comprise a diverse arctic-boreal community. Many of the component species are near the southern limit of their geographical range at Plymouth and are found infrequently, if at all, south of Cape Cod. These species would presumably be less tolerant of thermal stress and are therefore observed as potential indicator species. Results of the latest data set were analyzed by ccmparing with prior results and by comparing data from the effluent sites with that from I 1 I
I control sites at Rocky Point and Manomet Point located 0.5 km aut 4 km distant. The results of these analyses can be separated into three groups: A. No effects of PNPS; B. Effects possibly due to PNPS; C. Effects definitely due to PNPS. 1.1 No Effects of PNPS At the mouth of the discharge there is a denuded area where a strong current in combination with elevated temperatures inhibits normal benthic community development. We are interested mainly in the area immediately adjacent to this, where the biota is influenced solely by the thermal component of the plume. PNPS discharge cooling water <ith a maximum AT of 16.2* C (Marcello, 1975), but the temperatures reaching benthos at our effluent study sites are considerably lower due to mixing. I BECo study (1980) which delineated denuded and stunted areas indicates the ten foot g (MLW) effluent rock site is located at the border of the affected and W denuded zones, where it is exposed periodically to the heated thermal current. The 20' sand station is located even further from the denuded zone, yet sediment characteristics, as observed in the course of this program and reported in previous BECo semi-annual reports, indicate it also is affected by the discharge current. Faunal analyses included determination of species richness, faunal densities, species dominance, community overlap, diversity, classification, and ordination. Algal analyses included biomass and g community structure, community overlap, growth rates, reproductive B periodicity, plant and animal colonization of Chondrus and Phyllophora, and Laminaria density. Of these, most analyses displayed no observable effects of the thermal discharge in the PNPS area, as discussed below. Faunal community composition indicated there was no major difference between the effluent site and controls. Species richness was similar as was richness seasonality, phylogenetic composition, and composition of
" opportunistic" families. Total densities and densities of seven dominant species were also similar. Diversity indices and principal components ordination analysis likewise suggest a basic similarity between control and effluent sites. The dominant biota at the effluent I
2 I
f L also dominated control areas, indicating no major disruption of the L indigenous benthic community at the effluent site. Analysis of algal community overlap, plant and animal colonization of Chondrus and Phyllophora, Laminarla blade length, Laminaria density, and Laminaria reproductive periodicity revealed no substantive differences between control and experimental stations. 1.2 Effects Possibly Due to PNPS Thermal stress may be responsible for a variety of dissimilarities found between control and effluent sites. Although analyses of { community characteristics elucidate these differences, causal relationships are difficult, if not impossible, to demonstrate. Many factors influence community structure in the shallow subtidal, including exposure to wave action and differences in substrate characteristics. It is difficult to separate the effects of these unavoidable factors from those due to thermal loading. Faunal studies indicate thermal addition may be responsible for the slightly abnormal faunal community structure at the effluent 10' rock site. Lower community overlap values of effluent sites with controls, with previous data, and among replicates indicate the effluent site is more variable over both time and space. Classification analyses support this, as effluent replicates sorted incorrectly or at extremely low similarity values compared to control sites. The effluent r.rea is composed of rock interspersed between sand areas. The additional spatial heterogeneity may be responsible for the increased spatial variability at this site. However, periodic or localized disturbance by the discharge current or by thermal loading could also result in dissimilarities in community composition which would be expressed as temporal or spatial variability. Although it is difficult to distinguish between the sources of variation, we sus tct a combination of factors is responsible for the observed difference- nt the effluent site. Thermal loading appears to be influencing densities of four fatnal species in the effluent area. In our last report (BECo, 1979) a late { settlement of juvenile Modiolus modiolus at the effluent site was believed to be due to therm ; addition. Present data again chow greater
- . mussel densities and dominance at the effluent. Although this trend has 3
I not been observed consistently throughout the study, there is accumulating evidence that mussel recruitment or growth may be enhanced by the thermal discharge. Densities of two common amphipods also suggest discharge disturbance may be affecting community characteristics. Caprella penantis densities were enhanced at the effluent compared to Rocky Point, while Pleusymtes glaber was reduced at the effluent compared to both controls. Previous results disclosed similar findings, but since neither species is close to its geographic limits at PNPS, no causal relationship g can be proven. 5 To date only one faunal species consistently appears to be limited by thermal loading. Margarites umbilicalis is a gastropod living in the southern limit of its geographic range at Plymouth. Densities of this species have been significantly reduced at the effluent site compared to controls. However, Margarites is herbivorous and lower densites of Laminaria, its preferred food, at the effluent may be responsible for the reduced densities of the snail at this site. The gastropod is not extremely abundant at any site and its absence from the effluent site should not have any great impact on the food web there. Algal studies showed overall increases in Chondrus, Phyllophora, and total algal biomass over the previous year throughout the survey area. I 5 Increases in Chondrus and total algal biomass were greatest at the effluent, while increases in Phyllophora biomass occurred in approximately equal proportion at all stations. The present collections mark the second coasecutive year that biomass values have increased; because the greatest increases have occurred at the effluent station, Pilgrim I may be partly responsible for this enhanced production. 1.3 Effects Defintely Due to PNPS The most obvious effects of PNPS are seen in the direct path of the discharge. Current scouring in this area is responsible for a denuded area extending approximately 80 meters in front of the discharge (BECo, 1980). In past reports periodic, localized current scouring at l the faunal 20' (MLW) sand station was cited as being responsible for sediment patchincss, resulting in low replicate overlap and low station ' l overlap with previous data. Classification analyses also show low l 4 I
I similarity of sand station replicates. The 20' sand station was recently moved from10' (MLW), where impact due to physical effects of the discharge current was even more pronounced. However, a recent study by Boston Edison (1980) suggests the proximity of the sand stations to the rock-sand interface which transverses the area may also be responsible for increased variability in sediment grain size at these sites. Algal studies showed that Chondrus and total algal biomass values I fluctuated more widely at the effluent than at the two control stations. The effluent also evidenced a trend of lower Chondrus and higher Phyllophora biomass than Manomet Point and Rocky Point. It is hypothesized that current and sedimentation associated with the discharge stunt Chondrus growth at the effluent, and consequently permit the more rugge ; Phyllophora to outcompete Chondrus for space. All of these effects are localized and reversible. There is no indication that the continued propagation of a balanced, indigenous I benthic community in Cape Cod Bay is endangered by the restricted effects noted so far. I I I I I I I I
- I 5
l
i
- 2. INTRODUCTION This report contains results of benthic algal and faunal studies conducted in the vicinity of Pilgrim Nuclear Power Station ( PNPS),
Unit 1, Plymouth, Massachusetts. PNPS is a 655 MWe nuclear steam g! electric generating station located on the northwest shore of Cape Cod Wi , Bay, five miles southeast of Plymouth Harbor. ' The algal and faunal data presented here were derived from field ! collections and monitoring conducted during September and December, 1979. Re-evaluation of the survey program during the spring and summer of 1979 led to modifications in the scope of the program. These modifications, as recommended by the Pilgrim Administrative-Technical Committee (PATC) and approved by Boston Edison Company, included discontinuation of all intertidal studies with the exception of the Ascopht/llum nodosum growth study, as well as elimination of the control sand site White Horse Beach, and of faunal biomass determinations. All data were analyzed and compared with data from previous samp-lings and with control station results using a cocmunity structure approach. Specific data on algal biomass, reproductivity of kelp, dominant faunal species and densities of particular indicator species were also investigated. Identification and analysis of all faunal materiel was supervised and directed by Dr. Allan D. Michael and Carol A. Hibbard. Botanical identification and analyses were supervised by Walter Grocki. All personnel involved with the compilation of this report were active participants in all aspects of the project. . I I I I I 6
I I 3. METHODS The sampling methods used in the 1979-1980 survey were derived from techniques used by previous investigators with alterations made by Taxon with the approval of Boston Edison Company, to enhance the quality of data generated. In 1979 the survey program was re-evaluated and various changes in field stations and sampling methods incorporated. These I changes include the elimination of intertidal nondestructive monitoring, intertidal fouling studies, the subtidal 20' sand control station White Horse Beach and of faunal biomass determinations. 3.1 Sampling Stations Sampling and observation of the benthic biota were conducted along three subtidal transects perpendicular to the shore (Figure 1). Originally the Rocky Point stations were monitored as far-field experimental sites, with the effluent rock site as the near-field experimental station, and Manomet Point as the rocky control. No evidence of any discharge-related effects was discovered at Rocky Point in any of our subtidal studies and since the station appeared to be a good control area, it will be so designated in this report. The White Horse Beach 20' (MLW) sand control site was dropped in September. Previous data from the effluent sand station will be used as an auto-I control against which future results can be compared. Location of the transects is as follows: The northernmost transect, Rocky Point (RP), was established by lining up the mir relay tower I and the off-gas stack. To the south of Rocky Point was the effluent transect, which was identified by the axis of the effluent canal and included the effluent rocky site (ER) and the effluent sand site (ES). The third transect, Manomet Point (MP), was identified by lining up the two southernmost telephone poles on top of Manomet Point. The rocky stations (RP, ER, and MP) were sampled at 10' (MLW) for fauna and algae. The sand station was sampled at 20' for fauna only. Figure 1 shows the actual station locations along each transect. Our station location techniques were sufficient to assure that all collections designated from a single station were made within a radius of 25 - 50 meters at a given depth. .I
i l l I ys i
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;.~,, - lf$$.y : f-f-c4y7 S;;[,fg.7:gy;Q.<,;&?$'ifiGas:s?llv FIGURE 1. Eccation of transects for benthic sampling in the I
vicinit!1 of Pi1.]ritn Nucle.sr rcwer St.ation. B I
l L 3.2 Sampling Methods 1 At each of the subtidal rock substrate sites, quantitative algal l 1 and faunal samples were collected using a pipe frame quadrat, 33 cm on a side (1089 cm ). The quadrat was placed on a flat rock and all attached flora and fauna within the limits of the quadrat were scraped off the rock surface with a scraper and sucked up into a 0.5 mm mesh bag, using the device shown in Figure 2. Three quantitative samples were taken at random at each site and were fixed in 10% formalin. The algal and faunal components of the samples were separated by rinsing the animals off the algae into a 0.5 cm standard mesh screen, and preserving them in 70% ethanol. The algal fraction was then returned to 10% formalin. At the sand ststion divers descended to the bottom and, using the sand sarraler shown in Figure 3, recovered three 25 cm x 25 cm x 7.5 cm (4687.5 cm ) samples. Samples were returned to the lab and fixed in 10% formalu. The animals were separated from the sand substrate by sieving the sample through a 1.0 mm standard mesh screen. The animals thac were retained on the screen were preserved in 70% ethanol. 3.2.1 Faunal Studies Faunal quantitative samples were stained with a solution of rose bengal and alcohol prior to sorting. Sorting of the samples was completed in two steps. Presorting involved removing the faunal material j from the residue and identifying it to major groups and families. This sorting was done using a binocular dissecting scope with a magnification range of 7 to 40 power. Due to the non-quantitative sampling of spirorbid worms and colonial ectoprocts, only qualitative representatives of these species were retained for identification. Species with very high density, such as Mytilus edulis and Modiolus modiolus, were lef t in the residee and counted there. Final sorting was done by qualified taxonomists using binocular dissecting and compound microscopes. Individual animals were identified to species whenever possible. A reference collection is maintained of all species previously encountered and is expanded as additional species are found. At each sand site, a sediment sample was taken for grain size { analysis by taking a two ounce sediment core from the bottom. The r 4 l - - - - - - - _ _ _ 1
I I Removable Catch Bag of 0.5 mm. Nytex Mesh s i s O Valve to Regulate
'7 r ' Air Flow ws===s :
E I Plastic Tube g Air h Flow v Standard g Scuba Tank 9 Suction Created by Upward Flow of Air I I , (33 cm2) Pipe Frame to Delineate l i Quadrat FIGURE 2. Rock substratum airlift sampling device. I 10 I, L I
L L SIDE VIEW E y top ol O.Smm mesh net - 7.5 cm [ u c= =;= = -
=h- - =
E ' ' 25cm l i I OBL10UE VIEW handles / [
/ l stainless steel floor I slides in groove to cut shcrpened edge
[ off sompte [ FIGURE 3. Sand substratum sampling devica. ( 11 ( - _ --- -
l sediment core was dry sieved through a standard phi-series of sieves (2 mm, 1.0 mm, 0.5 mm, 0.25 mm, 0.125 mm, 0.062 mm) using a Rx-24 portable sieve shaker. The six fractions were dried in an oven for 24 hours and weighed. The percentage of each class size was calculated and is reported in the sediment analysis section. 3.2.2 Algal Studies 3.2.2.1 Algal Biomass Studies Algal subsamples collected from the Rocky Point, Manomet Point, and effluent 10' quantitative stations were separated into five fractions: Chondrus crispus, Phyllophora spp., epiphytes of Chondrus, epiphytes of Phyllophora, and the remaining benthic species. Each remaining benthic species and epiphytic fraction was then identified and an estimation of the realtive abundance of the algal species comprising each fraction was made. Dry weights for the five fractions were taken after 72 hours in a drying oven set at 80* C. Before drying, Chondrus and Phyllophora biomass fractions were compared with two sets of five standard samples that showed increasing degrees of plant or animal colonization. The samples of the standards were ranked from one to five, in order of increasing colonization. Each algal fraction was given the values of the standard it most closely matched in degree of plant epiphytization and animal encrustation.
" Colonization values" for plant epiphytization and for animal encrustation were then derived for each station by adding the values assigned to the tn m subsamples. Thus each biomass sample of Chondrus and Phyllophma received one "coJonization value" for the plant epiphytization and a second " colonization value" for the degree of animal encrustation. We I
l have termed the sum of these two colonization values " condition index". The sum of the condition indices of the Chondrus and Phyllophora for each station was the condition index value of the Chondrus/Phyllophora association for the collection. I I l 3.2.2.2. Laminaria Survey The first of two semi-annual Laminarla surveys was concluded in January, 1980 at Rocky Point, effluent, and Manomet Point. The Rocky Point and Manomet Point survey sites were positioned directly shoreward 12 I
I along the ten foot quantitative survey transects; the effluent survey site was positioned approximately fifty meters south of the effluent ten foot quantitative survey transect. All survey sites were located at a depth of seven feet. l At each survey site, a weighted ten meter section of polypropeline line, marked at one meter intervals with short lengths of red surveyors tape, was set out parallel to the shore. A one meter square metal i quadrat was placed adjacent to the line at each meter square interval, and all kelp plants within the quadrat were identified to species (Laminaria digita or L. saccharina), counted, measured, and observed for I l the presence of soral (reproductive) development. 3.2.2.3 Ascophyllum nodosum Grouth Study l The Ascophyllum nodosum growth study was reinst.ated in February, 1980 at the Rocky Point, Manomet Point, and effluent stations. In order to insure sampling continuity, the transects whicL had been used for the Ascophyllum nodosum study in previous years were again selected for the b current study. The three transects. which represent equivalent biological zones, were originally established in June, 1977. The actual ( tidal elevation of each transect was determined by transit readings taken in August, 1977: the Rocky Point and effluent transects proved to be at close h comparable tidal levels of 0.67 m and 0.54 m (MLW) respectively; the Manomet Point transect was shown to be at 0.02 m (MLW). At each transect, 25 healthy, medium-sized plants were selected and marked with numbered plastic tags secured about the base of each plant with plastic cable ties. Plants growing in particularly exposed or particularly sheltered niches were avoided. Plants encountered along each transect which could be identified as having been used in the August, 1978 - July, 1979 study were recruited into the current study. Five main ! growing axes with complete and healthy apices were selected from each 1 plant and identified with colored plastic tape attached to each tip with 1 small plastic cable ties. The length of each such tip, from the base of l the most recently formed bladder (including the bladder in the l 1 measurement) to the apex, was measured to a precision of one millimeter and recorded. The same tips were measured again at monthly intervals. i Lost or damaged tips were replaced to maintain a sample size of 125 l specimens at each transect. , 13
I 3.3 :atistical Analysis The number of faunal individuals for each species was tallied on species lists, the sums for the three subsamples added and this numerical data was then transposed onto FORTRAN data cards. Statistical data analysis was performed in the BECo IBM 370 and the Woods Hole Oceanographic Institute's (WHOI) Sigma 7 computer. Diversity coefficients, including Brillouin and Shannon-Wiener formulas, were calculated on replicate data and on the combined data. A classification (coefficients of similarity) analysis was performed on the replicate data and is presented graphically in the form of a hierarchical dendrogram. The diversities were calculated using the WHOI program PRARE 1, and classification used the Virginia Institute of Marine Science program COMPAH by Bosch. Factor analysis was performed using the Biomedica E Computer Program (BMDP) at WHOI. Results of analysis by station for 3 normal data are presented in a scattergram. Community overlap of faunal species and of algal species was l determined using Jaccard's coefficient of similarity (Grieg-Smith, 1964). This method used the formula Cg , cjj A 3
+ A -
c 3 33 where cg = numbers of species in common between the two sites, Aj = number of species at site 1, and A y = number of species at site J. I This method of estimating overlap considers only the number of species I in each sample and those shared. It does not take into account actual abundances of these species. Quantitative data was considered in the E coefficient used to calculate similarity values as part of chssification 5 analysis. I I I 14 I I
F L
- 4. FAUNA e
4.1 Faunal Systematics 7 Analysis of samples taken at ten foot (MLW) rocky stations and at L the twenty foot sand stations during September and December, 1979 l resulted in the addition of 17 new species or cater ^r'.es to the previous b % composite faunal species list of five years work in the Plymouth area (Appendices 1 & 2). In four cases specimens were identified only to F L genus or family level, due to the poor condition or lack of maturity of the animals. Although we are reluctant to group specimens under general { headings, we prefer to do this rather than arbitrarily assign imperfectly preserved or immature specimens to species designations already in use. In addition to the new categories, two name changes were incorporated, reflecting intensive study by our taxonomists of the order Nudibranchia. I In the phylum platyhelminthes the turbe11arian Monoophorum sp. was identified from the effluent sand site. This short cylindrical member of the order A11oeocoela is common on Ulva where it resembles a chalky white lump until disturbed. In the past platyhelminthes members were grouped under a general phylun heading. However, the specimen observed in ( September was in excellent condition making possible identification to the family level. Ten additions were made to the phylum Annelida. These included two { sabellids, Laonome kroyeri and a specimen whose condition allowed identification to the genus level, Chone sp. In the family Spionidae, six specimens of Polydora socialls were identified, and the family category Spionidae was used to classify a juvenile specimen too immature for further identificaticn. Two terebellids, Trichobranchus sp. and Amphitrite Johnstoni, were described as were the pectinariid Pectinaria ( granulata and the magelonid, Nagelona rosea. In the family Polynoid'ae, further study of the previously described species Harmothoe enabled us ( to separate this group into two species, H. imbricata and N. extenuata. l These two species are of ten caftased and-lumped into a single species description (Pettibone, 1963). Finally, a capite111d was collected which {- is unrecorded in the current literature. This species, called Amastigos n.sp. in this report, is being described by Dr. Daniel Dauer of Old [u . Dominion University. (~ '15 r ---- - -
Studies during September and December also added six species to the phylum Arthropoda. These included two pycnogonids, Nymphon Grossipes and Phoxichilidium femoratum, both common sea spiders of northern New England shallow waters. Two decapod crustaceans, the hermit crab Pagarus arcuatus and a spider crab which was identified to the a family level as Majidae, were also found. Phyxus abdominalls, an isopod parasitic in shells occupied by hermit crabs, was identified from Manomet Point. One further addition to the species list at the generic level was Cirripedia. Barnacles are often poorly sampled by our techniques and identification beyond the subclass category is difficult when the shell is missing, as in the present case. In the phylum Mollusca two name changes of nudibranchs were incorporated. After careful examination of current and past specimens we g determined the species previously listed as rubranchus pallidus was in W fact Aeolidia papillosa, a large nudibranch common as far south as Woods Hole. The species previously described as Nudibranch sp. C was identified as Facelina bostoniensis. 4.2. Faunal Community Descriptions 4.2.1 Rock Stations Benthic communities at ten foot (MLW) sampling sites have remained basically similar since t.he start of the project in September, 1974. All stations are composed of rocks ranging from small pebbles to large boulders of several cubic meters. This creates a very heterogeneous B environment with a highly diverse faunal community well established 5 within a luxuriant algal mat. At the effluent the boulders are separated by banks of sand and gravel and the algal mat is less dense than at the control sites. Rock site communities comprised a diverse assortment of faunal species, representing every major phyla. Molluscans were most numerous during both September and December when dominance by the horse mussel Modiolus modiolus and the snail Launa vincta reached 90% of total populations. Both species have been dominante at the rock sites before: Modiolus, in particular, is traditionally the most numerous of any species and its current high densities reflect a recovery from a poor recruitment in 1978. = 16 I
[ The phylum Arthropoda is well represented in terms of species richness at rock sites. Members include numerous numerical dominants such as the amphipods Jassa falcata, Ischyrocerus anguipes, Pleusymtes glaber, Dexamine thea, Pontogeneia inermis, and Corophium bonelli as well as the capre111ds Capre11a penantis, and Aeginina longicornis and the isopod Idotea phosphorea. Densit! N of these arthropods are typically high, although their relative contribution to total population is governed by fluctuations in Modiolus densities. Numerous annelid r- les are also found at rock sites, although densities of these are usually rather low. Most common are Pholoe minuta, Harmothoe extenuata, Nereis pelagica, Nicolea venustula, Eulalia viridis, and Cirratulus cirratus. ( Several species from the phyla Echinodermata, Chordata, Ectoprocta, and Coelenterata were also often observed from rock sites although densities of these were characteristically low. The common sea-star Asterias forbesi was more numerous than in the recent past, due to the higher densities of its preferred prey, Nodiolus modiolus (Lubchenco and Menge, 1978 and BECo, 1980). Most of the A. forbesi individuals were very tiny, indicating their presence is a direct response to the successful settlement of Modiolus this year. 4.2.2 Sand Stations - Sand samples were collected from the effluent 20' (MLW) site in an area of fine sands covered by a thin layer of silt. The general bottom topography was flat, with small ripples on tha sand surface. The sediment here is generally coarse grained due to its proximity to the rock-sand interface which obliquely transverses the area (BECo, 1980). Six phyla were represented in the sand community. During both September and December the haustorid amphipod Protohaustorius deichmannae and the bivalve Tellina agills were numerical dominants. An assortment of other species including the annelids Spiophanes bombyx, Nephtys caeca, Phyllodoce arenae, Tharyx acutus, the isopod Edotea triloba, the l amphipods Photis macrocoxa and Jassa falcata, and the bivalve Spisula solidissima were also typical of the community. Echinarachnius parma, the sand dollar, was numerous in September but was not considered a dominant in December. [ 17 f .
I 4.3 Faunal Community Structure 4.3.1 Faunal Species Pichness Faunal species richness for the perkd December, 1978 through December, 1979 is presented in T:ble 1. These values are extracted from the combined replicate data and represent the cumulative number of species found in all replicates rather than the mean. number of species per replicate. Rock stations were clearly distinguishable from sand stations by their greater species richness, as in previous results. Rocky Point samples contained the greatest numbers of species (x = 78), followed by Manomet Point (x = 77) and the effluent rock site (x = 73). The effluent sand site displayed a considerably lower mean species richness (40) and at all times demonstrated fewer species than rock sites. The differences in species richness between rock and sand substrates is believed due to the greater variety of microhabitats (Simpson, 1964) and possibly higher productivity (Connell and Orias, 1964) in rocky areas compared to sand areas. Rocky stations were analyzed over the short-term (December, 1978 through December, 1979) and long-term (September, 1974 through December, 1979) using paired-difference tests (Mendenhall, 1975). Results of this test comparing species richness at the three stations are found in Table
- 2. No significant differences were found between stations using only the current data, however, when all historical data are included, Rocky Point contained significantly greater species richness than either Manomet Point or the effluent. Examination of historical data suggests higher species richness at Rocky Point (primarily during the period frot October, 1975 through January, 1978) is responsible for this significance.
Since richness was significantly lower at both the control site Manomet Point and the experimental effluent site compared to Rocky Point, no adverse effect due to thermal addition is indicated. In fact, richness E at the effluent site during September, 1979 was higher than any other 5 i recorded value for this study. Negative impact due to thermal pollution I should be most obvious during September, when high ambient temperatures in combination with the PNPS AT of 16.2* C should stress temperature tolerances of cold water species. This suggests the effluent discharge l 18
I i
~
I l l TABLE 1. Faunal species richness, densities of individuals including and excluding Modiolus modiolus/m2, and densities of Modiolus l modiolus/m2 during the period December,1978 through December, 1979. I 1 Date # Species N Individuals # Individuals # Modiolus excluding Modiolus December, 1978 l RP 10' 65 42020 38678 3342 I l ER 10' MP 10' ES 20' 61 58 36 38810 31402 4888 23883 29113 4872 14927 2289 16 March, 1979 RP 10' 83 44559 38427 6132 ER 10' 51 56460 34587 21873 i MP 10' 80 43274 36309 6965 ES 20' 45 6945 6940 5 l June, 1979 RP 10' 74 70932 69720 1212 ER 10' 80 31085 75210 5875 MP 10' 84 200475 197366 3'.09 ES 20' 37 4423 4412 11 September, 1979 RP 10' 87 98544 88177 10367 ER 10' 98 72100 60301 11799 MP 10' 82 153912 129297 24615 ES 20' 38 4994 4983 11 December, 1979 RP 10' 81 150552 52375 98177 ER 10' 77 659773 71047 588726 MP 10' 83 157792 55472 102320 ES 20' 45 12893 12072 821 i 19
I TABLE 2. Paired-difference test comparing faunal data for the periods December, 1978 through December, 1979 and September, 1974 through December, 1979. gTests compare species richness, numbers of individuals /m including and excluding Modiolus modiolus, community overlap, Shannon-Wiener diversity calculated including and excluding Modiolus, evenness, and numbers of Modiolus modiolus/m2, l y 12/78 - 12/79 9/74 - 12/79 n t p n t p Comparison Species Richness g RP > ER 5 0.618 25 2.774 <.05 g RP > MP 5 0.197 25 2.545 c .05 ER - MP 5 -0.545 25 -1.169
# Individuals RP - ER 5 -0.979 25 -1.774 RP - MP 5 -1.387 25 -1.970 g ER - MP 5 0.572 25 -0.843 g # Individuals excluding Modiolus .
t RP - ER 5 0.557 25 -1.003 RP < MP 5 -1.259 25 -2.460 <.05 ER - MP S -1.710 25 -1.737 Community Overlap RP/ER < RP/MP 5 -1.074 25 -4.604 <.01 RP/ER - ER/MP 5 2.116 25 1.011 g RP/MP > ER/MP 5 2.125 25 6.303 <.01 5 Diversity RP > ER 5 1.946 24* 2.266 <.05 RP - MP 5 O.871 24 0.714 E g ER - MP 5 -0.745 24 -2.011 Diversity excluding Modiolus l a RP > ER 5 0.932 i 20** 4.430 <.01 RP > MP 5 0.691 20 2.882 < 01 g ER - MP 5 -0.031 20 -0.569 5 Evenness RP - ER 5 2.530 21*** 1.358 g RP - MP 5 0.605 21 0.532 3 Ed - MP 5 -0.827 21 -0.987 l M Modiolus l RP - ER 5 -1.086 25 -1.808 l RP - MP 5 -1.490 25 -1.714 ER - MP 5 1.044 25 -0.743
- Data from November, 1974 through December, 1979.
** Data from Nov., 1974 through Sept., 1977 and Sept. 1978 through Dec., 1979. *** Data from August, 1975 through December, 1979.
20 I
I is having little negative effect on species richness, but gives no information on possible changes in species composition per se. This question was addressed by examining the relative numbers of species found in the major phylogenetic groups. The three rocky stations exhibited relatively similar phylogenetic composition. The high species richness value seen at the effluent site during September was due primarily to enhanced numbers of species in the arthropod and molluscan I phyla compared to previous findings at the same site and to findings at rocky control stations. All species found exclusively at the effluent site during September had been previously identified from the other rock sites and are common constituents of the indigenous community in the Plymouth area. Furthermore, when the phylum Annelida was examined for composinion of reputed " opportunistic families", i.e. syllids, orbiniids, capitellids, oligochaens, and spionids (Wass,1967 and Grassle, 1974) no difference was found in densities or species richness between the effluent and control sites. If the thermal discharge was stressing the community at the effluent site, one might expect enhanced representation in these I families, since early maturation and high mortality rates allow opportunistic species populations to increase rapidly in response to disturbed conditions. Seasonal variation in species richness is presented in Figure 4. All rocky stations demonstrated similar patterns with highest values in September. Only the effluent rock site differed noticeably with lower richness during March. Reduced representation in the phylum Annellida was responsible; hcwever, since annelid populations are not character-istically depressed at the effluent, the discharge is not considered to be a factor. l 4.3.2 Faunal Population Densities Densities of faunal organisms per square meter are presented in Table 1 and Figure 5 for the period December, 1978 through December, l 1979. As with species richness, densities were greatest at rocky sites l compared to the 20' (MLW) sand station (x = 6,829). The effluent rock site contained greatest densities (x = 908,228) compared to Manomet Point l (i = 117,371) and Rocky Point (i = 81,321).
- 21 I
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I Populations at rocky stations were influenced by densities of the horse mussel, Modlolus modiolus (Figure 6). A poor recruitment of this major community component during 1978 lowered total densities at all rocky stations. September samples demonstrated increasing numbers of the mussel with densir,ies caring December reaching 588,726/m . The phenonmenon of exaggerated density fluctuations caused by differences in mussel recruitment has been well documented in the Pilgcim study. Heavy settlement was reported for all years since 1974 with the exceptions of 1976 and 1978. The periods of poor recruitment and survival had no lasting effect on mussel populations, as seen by the most current results, and were evident at both control and experimental sites. g In the current data, mussel populations were greatest at the effluent W site during December. Statistical analysis of past data, however, g indicates this is not a consistent feature, as the control sites often 3 contained greater mussel populations during the coldest months. Faunal densities excluding mussels is presented in Table 1 and in Figure 7. Again rocky stations show similar seasonality with greatest summer densities and lowered numbers in the colder winter months. Results are influenced to a moderate degree by densities of the gastropod Lacuna vincta. This snail reached populations of 41,206/m at Manomet 2 2 Point, 20,019/m at Rocky Point, and 11,457/m at the effluent, densities higher than those observed in previous samplings. The species is E W analyzed further to detect differences between sites in Section 4.3.3. l Figures 5, 6, and 7 show there was good agreement in total densities, densities excluding mussels, and densities of Modlolus modiolus during _ j the past five sampling periods at all three rocky stations. A test of l these parameters with paired-difference analysis substantiates this, as no station comparisons yielded statistically significant results. Densities dating back through September, 1974 were also analyzed with similar results (Table 2). One exception, that of greater non-mussel densities at Manomet Point compared to Rocky Point, has been reported in previous results. Variability in shallow benthic communities is well documented and results such as this are difficult to interpret. 24 I
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1 E 3 0 RP Z O ER 10 4-A MP 2000 ' ' 12 78 3f79 sf79 9/79 12/79 FICURE 7. Faunal densities excluding Modiolus modiolus por square meter at rock stations.
I 4.3.3 Densities of Individual Faunal Species In past reports the densities of seven common species were I investigated to determine what, if any, differences are found between s.estions. Table 3 shows the current densities /m of these species as well as the densities of three more species normally found at our rock sites. Nereis pelagica and Asterias forbesi were included as representatives of the phyla Annelida and Echinodemata. The importance of the gastropod Lacuna vincta in overall densities was noted in Section 4.3.2. It was further analyzed to determine whether station preference could be responsible for the enhanced non-mussel densities at Manomet Point. I Results of paired-ditference tests comparing stations over short-term (December,1978 through December,1979) and long-term (September, 1976 through December, 1979) are presented in Table 4. No differences between stations were statistically significant for short-term data, with the exception of Caprella penantis. This caprellid displayed enhanced densities in both current and historical data at the effluent compared to Rocky Point. Differences in abundance between the effluent and the other control site (MP) were not significant. Densities of the amphipod Pleusymtes glaber were reduced at the experimental effluent site compared I to control sites in the long-term data. This has been observed previously and although short-tem results were not significant the low number of data points in the short-tem study may mask the effect. Neither of these species are at the edge of their temperature ranges in the Plymouth area (Bousfield, 1973 and McCain, 1968) and they should not be exhibiting a direct response to the heated effluent. We will continue to monitor their densities and hope to clarify any interactions with the discharge or with other community components which may be responsible for the observed differences in density. l One other species displayed reduced densities over the long tem at the effluent compared to both control sites. Nargarites umbilicalls is a cold water gastropod living in the southern extreme of its themal range in the Plymouth area (Morris, 1973). It has repeatedly shown lower l densities at the effluent and appears to be negatively affected by the elevated temperr.tures in the discharge area. However, this tiny snail is herbivorous, showing a marked preference for Laminaria. A recent study 27 .E
I I TABLE 3. Densities (numbers of individuals /m2 ) of ten dominant faunal species for September,1979 and December,1979. Il l SPECIES RP ER MP September, 1979 Aeginina longicornis 4413 1016 3017 Astorias forbesi 184 245 667 Capre11a penantis 7197 8182 9700 Ischyrocerus anguipes 10477 1518 5912 E Jassa falcata 10049 7454 16316 Lacuna vincta 20019 11457 41206 Margarites umbilicalls 4431 .208 4676 Modiolus modiolus 10367 11799 24615 tiereis pelagica 135 404 1126 Pleusymtes glaber 6573 2950 10588 December, 1979 Aeginina longicornis 643 459 759 Asterias forbesi 214 422 147 Capre11a penantis 5985 7748 1573 Ischyrocerus anguipes 4761 13452 5251 Jassa falcata 8238 13231 11836 Lacuna vincta 7962 1304 7803 Margarites unbilicalls 1261 37 734 Modiolus modiolus 98177 588726 102320 Nereis pelagica 190 477 337 Pleusymtes glaber 1652 4419 7417 I I 28 I I
L YABLE 4. Paired-difference tests comparing densities of ten dominant faunal species during the periods December,1978 through Decembero 1979 and September, 1976 through December, 1979. l 12/78 - 12/79 9/76 - 12/79 n t p n t p , 1 Aeginina longicornis RP - ER 5 1.209 16 2.064 ; RP - MP 5 0.112 16 -0.377 l ER - MP 5 -2.225 16 -1.526 Asterias forbesi RP - ER 5 0.977 16 -1.393 RP < MP 5 -1.878 16 -2.441 <.05 ER - MP 5 -1.747 16 -1.743 Capre11a penantis RP < ER 5 -3.285 .05 16 -2.443 <.05 RP - MP 5 0.191 16 -0.787 ER - MP 5 1.304 16 1.856 Ischyro:erus anquipes RP - ER 5 0.688 16 -0.574 RP - MP 5 -0.802 16 -1.448 ER - MP 5 -0.986 16 -1.737 Jassa falcata I RP - ER RP - MP 5 5 0.203
-1.075 16 16 -1.872 -2.009 ER - MP 5 -1.008 16 -0.980 Lacuna vincta RP - ER 5 0.183 16 0.717 I i? - MP ER - MP 5
5
-1.342 -1.284 16 16 -0.889 -1.263 Margarites umbilicalls RP > ER 5 1.878 16 3.543 <.01 RP - MP 5 1.196 16 1.069 ER < MP 5 -1.422 16 -2.621 <.05 I 29 l
m uma _ _ _ _ _
I I TABLE 4 (continued) I 12/78 - 12/79 9/76 - 12/79 n t p n t p Modiolus modiolus RP - ER 5 -1.086 16 -1.411 RP - MP 5 -1.490 16 -1.475 ER - MP S 1.044 16 -0.844 Nereis pelagica RP - ER 5 -2.447 16 -1.822 g RP < MP 5 -1.524 -2.636 ER - MP -0.794 16 <.05 5 5 16 -2.056 l Pleusymtes glaber RP > ER 5 0.976 16 2.294 <.05 RP - MP 5 -2.341 16 -2.017 g ER < MP 5 -2,297 16 -2.223 < . 05 5 I I I I I I I i t 30 I I .
L [ . (BECo, 1980) indicates Laminaria stock is reduced in the effluent area and Cais factor may explain the lower Margarices densities. The species is never extremely abundant at any of our study sites, nor does it [ contribute much to biomass. Its absence, therefore, should not seriously disrupt food web characteristics at the effluent site. However, the { reduction in densities at the effluent indicates the area is being stressed by thermal loading. ( 4.4. Faunal Species Dominance Numerical dominance in percentage of total faunal population for [ September and December, 1979 is presented in Tables 5 and 6. Is September rock samples Iacuna vincta was the major community component { reaching highest densities of 41,206/m at Manomet Point where it
)
comprised 26.77% of the total population. Densities were slightly lower I at Rocky Point and especially at the effluent, where it ranked second in numerical importance, but all sites showed greater L. vincta populations than most previous samplings. Dominance by the snail was reduced again in December due both to lower densities and to increased dominance by the horse mussel Modiolus modlolus. Modiolus is normally a major dominant at our rock sites, however, densities vary depending upon the success of recruitment in any ( particular year. September samples displayed moderate mussel densities, manifesting recovery of the mussel population from an unsuccessful I [ recruitment during 1978. Dominance was even more pronounced during December when densities at the effluent reached 588,726/m or 89.23% of the total population. September rc.ek samples were characterized by having numerous dominant species, each with moderate densities. In December, the overwhelming dominance by Modiolus reduced the number of species containing 2% or more of the total population, although densities of these species were similar ( to those seen in September. The co-dominants are primarily a group of amphipods including J a sa falcata, Ischyrocerus angulpes, Pleusymtes { glaber, and Dexamine thea and the capre111d, Caprella penantis. This group has been important in most samplings since the onset of the study, although their hierarchical placements vary over time and are not always { ' consistent at all stations. [ 2
's
TABLE 5. Numerical dominance of faunal species found at rock and cand stations during September,1979. ROCKY 10* STATIONS ROCKY POINT % EFFLUENT % MANOMET POINT % Lacuna vincta 20.31 Modiolus modiolus 16.36 Lacuna vincta 26.77 Ischyrocerus anguipes 10.63 Lacuna vincta 15.89 Modiolus modiolus 15,99 Modiolus modiolus 10.52 Capre11a penantis 11.35 Jassa falcata 10.60 Jassa falcata 10.20 Jassa falcata 10.34 Pleusymtes glaber 6,88 Capre11a penantis 7.30 Dexamine thea 1.28 Capre11a penantis 6,30 Pleusymtes glaber 6.67 Corophium bonelli 4.36 Dexamine thea 4.56 Dexamine thea 5.34 Amphithoe rubricata 4.28 Ischyrocerus anguipes 3.84 w Margarites umbilicalis 4.50 Pleusymtes glaber 4.09 Margarites umbilicalls 3.04
" Aeginina longicornis 4.48 Idotea phosphorea 3.36 Hiatella arctica 2.91 Corophium acutum 2.94 Pontogencia inermis 2.48 Amphithoe rubricata 2.08 Pontogencia inermis 2.57 Ostracoda 2.39 Calliopius laeviosculus 2.34 Ischyrocerus anguipes 2.10 Amphithoe rubricata 2.11 SAND 20' STATION EFFLUENT SAND %
Protohaustorius deichmannae 35.22 Tellina agilis 24.01 Edotea triloba 10.24 Jassa falcata 6.62 Sphiophanes bombyx 2.99 Diastylis polita 2.77 Echinarachnius parma 2.24 Phyllodoce arenac 2'.03 m m m m W m M M M M M M M M M M M M M
W W W W W W W W W W W W D M IV f l TABLE 6. Numerical dominance of faunal species found at rock and sand stations daring December,1979. ROCKY 10' STATIONS ROCKY POINT % EFFLUENT % MANOMET POINT % Modiolus modiolus 65.21 Modiolus modiolus 89.23 Modiolus modiolus 64.84 Jassa falcata 5.47 Ischyroceras angulpes 2.04 Jassa falcata 7.50 Lacuna vincta 5.29 Jassa falcata 2.01 Lacuna vincta 4.94 Dexamine thea 4.71 Pleusymtes glaber 4.70 Capre11a penantis 3.98 Ischyrocerus anguipes 3.33 , w l u Ischyrocerus anguipes 3.16 Cotophiwn bonelli 2.93 SAND 20' STATIONS EFFLUENT SAND % Protohaustorius deichmannae 42.00 Tellina agilis 15.30 Spiophanes bombyx 9.38 Modiolus modiolus 6.37 Tharyx acutus 3.88
- tis macrocoxa 3.31
- :sula solidissima 2.94 Nephtys cacca 2.56 Archiannelida 2.44 Edotea triloba 2.07
I l The effluent sand station was dominated by Protohaustorius 5 delchmannae and Tellina agills during both September and December. Numerous other species (8 for September and 6 for December) were present in densities exceeding 2% of the total population, and dominance was more evenly spread over these components than is usual at sand sites. Included were several species never before considered as dominants, such as the isopod Edotea tilloba, the cumacean Diastylis polita, the l amphipods Photis macrocoxa and Jassa falcata, and the annelids Phyllodoce arenae and Spiophanes bombyx. Noticeably absent was the haustorid l amphipod Acanthohaustorius millsi, which was only present in low densities. With this exception and that of including more numerous co-dominants, dominance patterns at sand stations were similar to previous results for 20' (MLW) sand sites. 4.5 Faunal Community Overlap Community overlap between stations and replicates was computed ! using Jaccard's coefficient of community (Grieg-Smith,1964). The Jaccard formula is
'ij -C A3+A3 where C = number of species in common between station i and j, Aj = number of species at station 1, A = number of species at station J.
j This method measures similarity of species content of two stations without regard to species distribution. Abundance is considered in the determination of the similarity index, as reported in the classification section of this report. Overlap values for the period December, 1978 through December, 1979 are presented in Table 7, and range from a low of 41% between control and experimental sites to a high of 68% between control sites. The two most recent samplings (September and December, 1979) exhibited slightly greater overlap of control and experimental sites than observed during the previous three samplings. These values are similar to overlap of control sites. Paired-difference tests were used to compare overlap of experimental 34 I
I TABLE 7. Faunal community overlap between stations for the period December, 1978 through December, 1979. Date Stations RP/ER RP/MP ER/MP December, 1978 56.63% (46) 50.09% (41) 44.68% (37) March, 1979 41.83% (40) 67.67% (66) 41.23% (38) June, 1979 55.55% (55) 56.73% (57) 54.72% (58) I September, 1979 December, 1979 60.87% (70) 61.22% (60) 60.95% (64) 59.22% (61) 57.89% (66) 55.34% (57) TABLE 8. Faunal community overlap between replicates of stations for the periods September and December,1979. Date Stations Replicates l-2 l-3 2-3
.I September RP 66.22% (49) 59.04% (49) 58.23% (46)
ER 59.77% (52) 63.95% (55) 55.06% (49) MP 75.00% (51) 71.79% (56) 70.13% (54) ES 40.00% (14) 38.24% (13) 51.72% (15) December RP 59.46% (44) 60.29% (41) 58.67% (44) ER 64.62% (42) 56.00% (42) 60.56% (43) MP 71.05% (54) 65.82% (52) 69.33% (52) ES 52.63% (20) 61.11% (22) 47.62% (20) I TABLE 9. Community overlap between stations comparing September,1978 with September, 1979 and December, 1978 with December, 1979. RP ER MP ES september 60.19% (62) 48.03% (61) 63.92% (62) 16.36% (9)
.I December 53.06% (52) 47.37% (45) 61.46% (59) 33.33% (21)
I ( ) Number of species in cou: mon. I ' 35 il
I. and control stations with that of control sites. Current results (December, 1978 through December, 1979) were not statistically different, due to the low number of data points used. Long-term analyses (September, 1974 through December, 1979) show a definite pattern. Overlap of experimental-control pairings was significantly lower than - that of the control-control pairing (Table 2), but no difference was found when the two control-experimental overlaps were compared. This result, which has been observed consistently throughout this study, demonstrates the greater similarity of species composition of control sites compared to the effluent and suggests a basic difference in community parameters at the experimental site. Community overlap of replicates from the same station is presented in Table 8 for September and December, 1979. Replicate overlap of all g rock sites exceeded that of the sand site, with the effluent rock site 5 showing greatest variability. These replicate values are only slightly higher than corresponding rock station overlap, which indicates variability between stations is similar to that found between replicates taken from the same station. The low overlap found between sand station replicates reflects the patchiness of the effluent sand area, as discussed in Section 4.9 and in Report #14 (BECo, 1979). Community composition was further analyzed by computing overlap of recent data compared to that taken one year ago. This technique should help detect any changes in species composition over time. Results are shown in Table 9. Again rock sites displayed least change (highest overlap values) led by Manomet Point. The effluent had lowest overlap of any rock site suggesting species composition may either be undergoing a transition in the discharge area, or it may be more variable than at the control sites. Evidence from replicate overlap and coefficients of variation for community parameters and species densities supports the latter. The close proximity of the effluent site to the rock-sand zone (as discussed in BECo, 1980) may induce spatial variation resulting in less uniform species assemblages. More stressful physical conditions, caused by the discharge, could also reduce stability and result in the g greater variability at this site. The extremely low overlap of the B effluent sand September sample with the previous years data is due to the abnormally coarse sediment samples in September, 1978. Species 36
E composition is intimately related to sediment characteristics and the usual haustorid amphipod and bivalve community typical of fine sand was not present. 4.6 Faunal Diversity Diversity indices have long been used to provide a scalar representation of community distribution; i.e. the aggregation of various taxonomic and distribution features results in a single value which changes as the shape of the community distribution changes and which can be compared directly with values from other similar communities. [ Most diversity indices combine two main features, species richness and species abundance. Indices should respond to significant alterations of { community distributions, but sensitivity to changes in community parameters depends upon which index is used. This fact has led many l investigators to question the value of diversity in assessing community structure. Logan and Maurer (1975), in discussing the application of diversity indices to the study of thermal effects of a steam-generating plant discharge, concluded diversity is not a dependable index of change in community structure as measured by numbers of individuals and species, indicator species, and equitability. Changen, in community structure might be reflected by a change in diversity, but this could be either an increase or a decrease. Therefore, interpretation cf diversity values must be made with caution, since the values may not reflect even significant alterations in many parameters. The Shannon-Wiener diversity index is used in the Pilgrim study, primarily because of its wide application in the benthic marine field and because it is more sensitive to changes in community structure than most other available formulas. Luders and 011ngski (1976), in a critical review of diversity indices conclude the Shannon-Wiener index only performs well for radical changes in community distribution; e.g., it is ( only moderately sensitive to changes in species richness and is insensitive to changes in individual abundances and total populations. It implicitly equates evenness of species distributions with diversity. Information theory diversity and related parameters were calculated on untransformed combined replicate data and are presented in Table 10 and Figure 8. Shannon-Wiener diversity was high during September at all 37
I I I TABLE 10.
~
I Ir *;ormation theory diversity values for faunal studies. Values based on combined data for the periods September and December, 1979. September, 1979 Station H' H J' H' Max H' Min RP 10' 3.9504 3.9423 .6445 6.1293 3.5173 ER 20' 4.1121 4.0996 .6523 6.3038 5.2849 MP 10' 3.7806 3.7752 .6278 6.0224 2.1707 ES 20' 3.1583 3.0624 .6062 5.2094 0.4336 Decembero 1979 I Sta tion H' H J' H' Max H' Min RP 20' 2.2510 2.2462 .3711 6.0661 2.2843 ER 10' 1.3660 1.3641 .2277 6.0000 0.0094 MP 10' 2.3272 2.3224 .3879 6.0000 0.0209 ES 20' 3.1135 3.0660 .5703 5.4594 0.2252 N' = Shannon-Wiener I N = Brillouin J' = Evenness I I
,, I.
I
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, a- ,, x y NN O
e _ _ _ _ _g s - sy b - \/ \ s\ a 2- O RP O ER A MP O ER 1 i i i i i 12/78 3/79 6/79 9/79 12/79 VIGURE 8. Faunal diversity (Shannon-Wicnor) at rock and sand stations. i
I stations but decreased at rocky sites in December. December rocky sites were dominated by the mussel Modfolus mediolus, resulting in lowered evenness. The dependency of diversity values at rock stations on evenness, which in turn was determined by densities of Nodiolus, has been discussed in previous reports (BECo, 1978 and 1979). Diversity is extremely sensitive to alterations in evenness, as predicted by Luders and Olingski, but is only moderately sensitive to species richness. Correlation analyses support this as diversity was significantly correlated with evenness over the entire study period (R = .908, N = 63, p <.01) but was not correlated with species richness (R = .079, N = 72, p < . 05) . In turn diversity was negatively correlated with Modiolus densities (R = .596, N = 72, p < .01) as was evenness (R = .399, N = 63, p < . 01) . The impact of the successful mussel recruitment on diversity was eliminated by computing diversity indices on non-mussel data only. Results (Table 11) are much higher for both Shannon-Wiener diversity and evenness during December at rock sites. Values are decreased at sand sites and at rock control sites during September, since mussel populations were not extremely dense: the reduction in species richness caused by eliminating the species Modfolus was more important than the enhance.nent of evenness in determining diversity values. Unlike control sites liversity at the effluent rock site was slightly enhanced in Septenber by the removal of Modiolus. Modiolus populations were greatest at this ste:: ion and their removal enhanced evenness sufficiently to augment diversity values. As discussed earlier, interpretation of the above results must be made with care. Equitability of species composition is well documented by the diversity values, disclosing a slight difference between the effluent rock site and the control stations. Modlolus dominance at the effluent was more pronounced than at the controls; removal of Modlolus from calculations resulted in enhanced diversity during both months. The diversity parameters furnish little information on species richness characteristics and offer no information on changes in species composition, changes in densities of individual species, or changes in total populations. These factors are better addressed by community overlap analyses (Section 4.5), classification analyses (Section 4.7), and I 40 I
I 1 1 I I TABLE 11. Information theory diversity values computed excluding Modiolus modiolus for faunal studies. Values based on combined data for the periods September and December, 1979. l September, 1979 Station H' H J' H' Max H' Min RP 20' 3.8725 3.8637 .6340 6.1085 3.8360 ER 20' 4.1480 4.1334 .6599 6.2854 6.1371 MP lo' 3.7454 3.7392 .6242 6.0000 2.5061 ES 20' 3.1430 3.0488 .6079 5.1699 0.4224 I I Dececher, 1979 Station H' H J' H' Max H' Min RP 10' 3.7910 3.7,'76 .6272 6.0444 5.8874 ER 20' 3.5439 3.5343 .5929 5.9773 4.2575 MP 10' 3.9588 3.9457 .6623 5.9773 5.3307 ES 20' 2.9602 2.9116 .5455 5.4263 0.2332 I N' = Shannon-Wiener N = Brillouin J' = Evenness I l lI g 41 I .. l l
i analyses of the individual parameters of species richness and population densities (Section 4.3). j Shannon-Wiener diversity and evenness were compared over the short- l term (December, 1978 through December, 1979) and long-term (November, 1974 through December, 1979) using paired-difference tests. Results are presented in Table 2 and indicate no significant differences between rock stations over the recent data. Long-term analyses demonstrate significantly greater diversity at Rocky Point than at the effluent and greater diversity computed excluding Nodiolus at Rocky Point compared to both other rock sites. No significant difference in evenness was found. Since evenness and species richness are the two factors influencing diversity values, greater species richness at Rocky Point is responsible = for the difference between sites (Section 4.3.1). Again, since both control site Manomet Point and the experimental site contained lowered ( richness compared to Rocky Point, no thermal effect is indicated. 4.7 Classification Analysis Classification analysis was performed on untransformed replicate data from September and December, 1979, using Bray-Curtis percent similarity e and group average sorting, a clustering method widely employed in marine benthic ecology. Results are presented in the form of a dendrogram of similarity in Figure 9. Substrate type was the most important factor determining clustering, as can be seen by the low similarity of sand and rock station groupings (0.0083). The effluent sand sites formed a distinct cluster, within which season played an important, but not absolute, role in determining similarity. All December sand samples clustered at high similarity values (0.7604), while September sand samples clustered with themselver. or with the December samples at lower levels (0.4315). The September #2 sand replicate was distinct and clustered first with December samples. Densities of the haustorid amphipod Protohaustorius delchmannae and the bivalve Tellina agilis were greater at this site than at the other two September sand samples. This indicates the sediment of this particular replicate was fine sand, similar to that of the sediment core taken in December. As discussed in Section 4.9, the sediment at the effluent sand site is extremely patchy; replicates taken during one sampling period may 42 I
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Il exhibit distinctive communities dependent upon sediment characteristics in their immediate area. 1 Within the rock station grouping both season and locality were l important in determining clustering. Control replicates clustered by date at high similarity levels (0.7711 for December and 0.5557 for September). The only exception was Rocky Point replicate #3 for December. This sample contained greater Launa vincta densities than were found at other December control sites. It was therefore grouped with September control sites, which. tended to contain large L. vincta populations. Within the two large season groupings no differences were exhibited between the control stations. Of the six replicates from the effluent rock station only two grouped with the appropriate seasonal groupings. The remaining four formed two groups, which clustered with the remaining rock stations at low similarity levels. The two effluent December replicates contained unusually high Modiolus populations compared to control sites, while the two September ef fluent replicates displayed lower Lacuna vincta densities. These factors were at least partially responsible for the independent clustering of these four replicates. To summarize, substrate characteristics detemined initial separation of sand and rock stations. Within groupings of stations with similar substrate characteristics seasonality was of prime importance in defining clusters with the exception of the effluent rock sites. These grouped separately and joined the major rock grouping at low similarity levels. Again these results suggest some basic d.fferences between the communities found at the effluent and those found at both control sites. Clustering of the rock stations indicates the differences may be due to spatial heterogeneity of the effluent site due to its proximity to the rock-sand boundary which transects the area. 4.8 Faunal Ordination A principal components factor analysis was performed on combined replicate untransformed species-frequency data extracted from September and December faunal samples. Only the 55 most abundant species were used as input for the analysis, which was run at the Woods Hole
- Oceanographic Institute's computing facility using the University of l
E 5 44
l 1 l I l 1 California Biomedical Computer Program (BMDP) P4M. The purpose of this technique is to reduce a large set of variables I (in this case species counts) into a smaller number of independent l source variables or factors. These factors explain the variation in the
~
original data set in a more simplified manner, and although the actual l parameters expressed by each factor are not known, they can sometimes be deduced by inspection of the original data set. In this particular analysis, Factors 1, 2, and 3 explain over 97% of the variance in the data and addition factors were not considered. Figures 10, 11, and 12 show factor scores for the eight stations for all possible combinations of the three factors considered. All figures indicate a contrast between sand and rock stations, but this is most obvious in Figure 10. Rock sites scored strongly positively on Factor 1, while sand stations scored only weakly positively. Factor 1, therefore, appears to separate stations primarily on substrate l characteristics as expressed in the component species. Factor 2 also shows pronounced separation of rock and sand stations, but further separates rock stations into two groups. Inspection of the data set indicates differences in several species counts were responsible, primarily densities of annelids. September rock samples, which showed largest densities in this phylum, scored slightly negatively on Factor 2. December samples showed lower densities and scored slightly positively, while sand stations contained few or no annelids and scored strongly positively. Species outside the phylum Annedlida may also influence loading on Factor 2, but these were not so obvious. Figure 11 shows loadings for Factors 1 and 3. Again Factor 1 indicates the basic difference in species composition between sand and rock substrate stations. Factor 3, on the other hand, shows definite seasonality with September stations scoring moderately positively and December stations scoring moderately negatively. This grouping based on seasonality is dependent mainly on densities of the bivalve Modiolus modiolus. Densities of this mussel were greatest at all stations during December. The differentiation of stations based on seasonality is again apparent in Figure 12 which plots Factor 3 against Factor 2. These results indicate differences in species composition due to l substrate characteristics and seasonality were responsible for most of l 45 l l
. - 1.0 RP 12 .- E A MP 12 9 ER9 G ER12 LMP9 - .8 E RP9 - .6 .4 ES 12 3' O y -- .2 ES9 I I t i I t t i I I I I I f I 8 I I I O I g i s I i 5 l 5 I I I I I I I I 3 5 3 3 -1.0 .8 .6 .4 .2 .2 .4 .6 8 1.0 Factor 2 .2 Figure 10. Scattergram of faunal principal components analysis for the period Septami>cr and December,1979; Factor 1 vs Factor 2.
W W M M M l l
- 1.0 RP 12 MP 12 G ER 9 ER12 6 A "" ' .8 E RP9 .6 ~- *T) .4 k.
2 O ES 12 k N
.2 O ES9 I l l I i '
l l l l g f g g g g g g g g 5 3 5 5 5 5 5 I 8 I I 5 I I 3 I 4 l 3
-1.0 .8 .6 -4 .2 .2 A .6 .8 1.0 ~~
Factor 3 _L 2 . Figurc 11. Scattergram of faunal principal components analysis for the period September and December,1979; Factor 1 vs Factor 3.
4 w
-- O ES 12 OES9 .8 --. s m - -A R
o l c~ l
* . _2 ,
- ER12 O MP12M RP 12 , ,
I I I I I t i I f f I I f f a f 3 l l l 5 5 5 5 5 5 i B I I I 3 I I I I 3 3 g 3
-ID .8 .6 -A .2 .2 A .6 .8 1.0 ~ ~
Factor 3
- .2 9 ER9 1
AMP 9 E RP9
...s .
Figure 12. Scattergram of faunal principal components analysis for the period September and Decem1mr,1979; Factor 2 vs Factor 3. I g
the variance seen in the BECo benthic data. Factor 1 is based primarily on differences in substrate, while Factor 2 is less obvious and appears l to be the result of both substrate and seasonality as expressed in the densities of the component species of the phylum Annelida. Factor 3 again shows loading based on seasonality as expressed by densities of the mussel Modlolus. In no case did the effluent sites load separately from control sites. This supports our contention that effects due to 1 discharge interference are minimal compared to those due to natural perturbations, such as seasonal cycles and substrate characteristics. 4.9 Sediment Analysis Grain size analysis was performed on sediment cores obtained at the sand station at the time of sampling. Samples were dry sieved through a standard phi-series of sieves (2.0 mm, 1.0 mm, 0.50 mm, 0.125 mm, 0.062 mm) using a Rx-24 portable sieve shaker. Percent composition by dry weight for gravel, sand, silt, and clay fractions as well as for I particle size are presented in Table 12 for the September and December, 1979 samples. Both samples contained extremely low percentages of gravel and silt, with a slightly larger clay fraction. The remaining sand fractions were both well sorted, but had different modal size classes (Figure 13 ) . The September sample showed high percentages of both 0.250 mm and 0.125 mm grain sizes while the 0.250 mm class was relatively unimportant in December. Historical data show the coarser sediment found in September to be typical of most previous effluent 20' samples, while the December I fine sand sediment is typical of previous control station White Horse Beach sediment (BECo Report #13). Effluent sand sites have been characteristically patchy; species composition suggest grain size may vary even between replicates taken ac the same time. The discharge current from PNPS is believed responsible for sweeping away smaller sediment particles from the effluent sand site, and although the station was recently moved from 10' (MLW) to 20' to decrease this effect, the station still shows signs of physical interference by the current. A recent study by Boston Edison (1980), i however, suggests that proximity to the rock-sand interface in the area l may also effect grain size and spatial variability at the effluent sand 49
TABLE 12. Percent composition of sand substrate for the offluent 20' (MLW) sand station during September and December,1979. Date Size (mm) Gravel Sand Silt Clag g 5 5 i 8 5 5 I 2.000 1.000 0.500 0.250 0.125 0.062 0.031 0.004 September 0.17% 0.09% 0.24% 53.31% 39.16% 2.21% 0.00% 4.82% December 0.26% 0.07% 0.17% 3.85% 89.58% 3.55% 0.42% 2.10% M M M M * * * * " "
I I I O( - - 80- Septsmber I 60-40-o 20-
= 's I 1 E
o 0 , m m 2.0 1.0 0.5 0.250 0.125 0.062 0.062 V O -1 0 1 2 3 1 5 P o ,
.3 I I
0 100-
. i o :
E l' December d 80-I ; I 40-l l I 20- l O I mm 2.0 1.3 0.5 0.250 0.125 0.062 0.062 O -1 0 1 2 3 4 5 l Grain Size Figure 13 Percent composition of sand substrate for the effluent I 20' (MLW) sand station during September and December,1979. I II 51 l r -- ,
I site. Further sediment studies should help clarify actual causes of the I patchiness seen near the Pilgrim Plant. Review of faunal data for effects of the sediment size class change also suggests the phenomenon was due to spatial heterogeneity and not to a wide-spread effect. Community overlap of sand replicates was low while in similarity analysis sand replicates from the same month clustered separately. These data indicate sediment composition may vary considerably between replicates and the sediment core may or may not be representative of the other sand samples. I I I I I I I I I 52 I
I I 5. ALGAE 5.1 Algal Systematics The cumulative quantitative algal species list presented in BECo Report #14 has been retained in the present report. No additions to (or deletions from) the cumulative list have been made as a consequence of analysis of the September, 1979 and December, 1979 quantitative collections. As for all previous collections, species identifications and taxonomic determinations were based upon the works of Parke and I Dixon (1976), South (1976), and Taylor (1957). 5.2 Algal Community Description Throughout the survey area, the ten-foot (MLW) subtidal zone was domininated by a thick cover of Chondrus crispus and Phyllophora spp. Individuals of the species Polyides rotundus, Ahnfeltia plicata, Corallina officinalis, Gymnogongrus crenulatus, and Chaetomorpha i melagonium were commonly found growing in mixed populations with Chondrus and Phyllophora. The dominant epiphytes of Chondrus and Phyllophora were Spermothamnion repens, Polysiphonia spp., Cystoclonium purpureum, and ceramium rubrum. Large specimens of the brown algal kelp species Laminaria digitata and Laminaria saccharina were found throughout the survey area. The kelps, which were the largest and most conspicuous components of the algal community, occurred singly or in large clusters of up to one dozen plants. The crustose algal community in the subtidal region was composed of an extremely large and diverse assemblage of I species, and was dominated by Hildenbrandia rubra, Ralfsia spp. and Phymatolithon spp. E 5.3 Algal Community Overlap Community overlap was determined from quantitative samples to assess the degree of similarity in species composition between stations. Table 13 contains community overlap data for the September, 1979 and December, t 1979 collecting periods. A listing of the species recorded for each station from each collecting period is presented in Appendix 3. In September, both the Rocky Point - effluent and Manomet Point - effluent station pairs exhibited community overlap values of 80.00%, while the Rocky Point - Manomet Point Station pair showed an overlap I
I I TABLE 13. Community overlap (Jaccard's coefficient of community) for quantitative algal studies. Overlap between replicates taken at the same station and overlap between stations is l presented for September, 1979 and December, 1979. E I Replicate Overlap September 1979 December 1979 Rocky Point I
'-2 69.57 90.48 1-3 78.26 86.96 2-3 75.00 78.26 Effluent 1-2 68.97 70.83 1-3 72.41 69.23 2-3 81.48 70.80 Manomet Point 1-2 75.00 66.67 1-3 80.95 76.19 2-3 83.33 72.73 Station Overlap Rocky Point -
Effluent 80.00 85.19 Rocky Point - l Manomet Point 92.00 91.67 E Effluent - g Manomet Point 80.00 78.57 E 1 I I I-54 g, W!
I value of 92.00%. In December, overlap values of 91.67, 85.19 and 78.57%, were recorded for the Rocky Point - Manomet Point, Rocky Point - effluent, and Manomet Point - effluent station pairs respectively. The above data show that, for each station pair, overlan values were remarkably consistent in both collecting periods. In addition, the relative hierarchical positions of the three stations were maintained through the two collections: in each period, the highest overlap value was shown by the Rocky Point - Manomet Point pair, while lower and quite similar values were shown by the Rocky Point - effluent and Manomet Point-a effluent pairs. The above data are generally not consistent with data recorded from the previous year. Overlap values obtained from the current September, 1979 and December, 1979 collections were, for all station pairs, higher than the values recorded for the corresponding collections in 1978. In addition, the hierarchical pattern displayed by the three stations in the September, 1979 and December, 1979 collections was not consistent with the patterns which emerged from the previous year's data; in both September, I 1978 and December, 1978, the Rocky Point - effluent pairing produced the highest overlap value, while the Rocky Point - Manomet Point and Manomet Point - effluent station pairs produced lower and essentially similar values. The lack of strict conformity between current and previous years data does not necessarily indicate that changes in algal species composition have occurred at the various stations. As the current collections mark the beginning of only the second year of community overlap analysis of quantitative collections, no truly valid baseline data exist against which current data may be compared. 5.4 Algal Biomass Studies Several noteworthy changes in the analysis and reporting of algal biomass data have been introduced with the current September, 1979 and December, 1979 collections. As in previous reports, biomass values are listed separately for chondrus crispus and Phyllophora spp. However, the biomass category referred to as "other" in previous reports has been eliminated. In its place, separate biomass categories have been created for epiphytes of Chondrus, epiphytes of Phyllophora, and remaining l benthic species. The remaining benthic species include Ahnfeltia plicata, 55 I l
Il Polyides rotundus, Gymnogongrus crenulatus, Corallina officinalls, ll Desmarestia aculeata, Desmarestia viridis, Ulva lactuca, Gracilaria foliifera , and Chordaria flagelliformis. The above modifications, in permitting the differentiation of the non-Chondrus/Phyllophora fraction into benthic and epiphytic components, insures a more accurate and precise quantification of the algal population at each station. 5.4.1 Total Algal Biomass Total algal biomass values for September, 1979 and December, 1979 are included in Table 14. In September, the highest total biomass value (732.02 g/m ) was recorded at Manomet Point. The lowest value (514.38) was recorded at effluent, and an intermediate-level value (629.79) was recorded at Rocky Point. In December, the highest value (746.76 g/m ) was shown by effluent. The lowest value (474.84) was recorded at Rocky Point, and an intermediate-level value (561.94) was recorded at Manomet Point. g Comparison of the above data with data obtained from the 8 corresponding collecting periods in 1978 produced generally mixed results. The September, 1979 Manomet Point and Rocky Point values represent modest 3 increases of 18% and 14% respectively over the September, 1978 values, while the effluent value represents a considerable 49% increase. The December, 1979 Rocky Point value represents a 25% decline from the December, 1978 level, while the Manomet Point value represents a more modest decline of 7%; the December, 1979 effluent value, in contrast, represents a 35% increase over the December, 1978 value. The moderate fluctuations in total biomass seen for Rocky Point and Manomet Point between current and previous years data are typical of the fluctuations seen whenever data from two collecting periods are compared, and indicate that no appreciable increase or decrease in biomass has occurred at either station over the September, 1978 - December, 1979 period. The relatively sharp increases in total biomass values shown by effluent over the same period may indicate that the algal population is undergoing a transition at this station. In the previous report (BECo Report #14), data was presented which showed that biomass was increasing at the majority of stations within the study area, with the sharpest rate of increase occurring at those stations in closest 56
I I TABLE 14. Dry weight values (g/m ) for Chondrus crispus, Phyllophora spp. , remaining benthic species, epiphytes of Chondrus, epiphytes of Phyllophora, total epiphytic biomass, and total algal biomass from the ten foot quantitative stations , for the September,1979 and December,1979 collecting periods. Station September 1979 December 1979 ROCKY POINT I Chondrus crispus Phyllophora spp. Remaining benthic species 411.33 (65.31%) 106.41 (16.90%) 29.28 ( 4.65%) 256.11 (53.93%) 81.90 (17.25%) 52.89 (11.14%) Epiphytes of Chondrus 30.32 ( 4.81%) 37.48 ( 7.89%) Epiphytes of Phyllophora 52.43 ( 8.33%) 46.46 ( 9.79%) Total epiphytic biomass 82.77 (13.14%) 83.94 (17.68%) Total algal biomass 629.79 474.84 MANOMET POINT I Chondrus crispus Phyllophora spp. Remaining benthic species 402.18 (54.94%) 157.14 (21.47%) 20.04 ( 2.74%) 278.10 (49.49%) 181.23 (32.25%) 11.49 ( 2.04%) Epiphytes of Chondrus 36.76 ( 5.02%) 14.30 ( 2.54%) lI Epiphytes of Phyllophora Total epiphytic biomass 115.90 (15.83%) 152.66 (20.85%) 76.81 (13.66%) 91.11 (16.20%) Total algal biomass 732.02 561.94 EFFLUENT I chondrus crispus Phyllophora spp. Remaining benthic species 143.55 (27.91%) 174.90 (34.00%) 21.09 ( 4.10%) 398.85 (53.41%) 172.56 (23.11%) 25.44 ( 3.40%) Epiphytes of Chondrus 19.65 ( 3.82%) 15.94 ( 2.13%)
- I Epiphytes of Phyllophora Total epiphytic biomass 155.19 (30.17%)
174.84 (33.99%) 134.01 (17.95%) 149.95 (20.08%) Total algal biomass 514.38 746.79 I 57
II l proximity to the discharge. Current data appear to provide further ll ' evidence that biomass at efflue.nt may be increasing. g Manomet Point and Rocky Point registered total biomass decreases 3 of 25% and 23% respectively between the September, 1979 and December, 1979 collections. The lower December values are believed to reflect the elimination of numerous summer annual and pseudo-perennial species
~
from the survey area due to harsh autumn and winter storms. Effluent, in contrast, recorded a 45% increase in biomass between the two periods. The anomalous pattern shown by effluent is not particularly unusual. In previous years, decreases in biomass during the winter season have rarely been concurrently recorded at all stations. In the 1978 collections, only Manomet Point registered a decline in total algal biomass between the September and December surveys (BECo Report #14). 5.4.2 Chondrus crispus Biomass Chondrus biomass values for the September, 1979 and December, 1979 collections are included in Table 14 and Figure 14. In September, relatively high and essentially equivalent values of 411.33 and 2 402.18 g/m were recorded for Rocky Point and Manomet Point respectively; at effluent, a low value of 143.55 g/m 2was recorded. At both Rocky Point and Manomet Point, Chondrus constituted over 50% of the total biomass value; at effluent, Chondrus constituted only 27%. The low effluent Chondrus value was in large part responsible for the low total biomass value recorded for that station in September, 1979. In December, relatively low and again very similar Chondrus values of 256.11 and 278.10 g/m were recorded for Rocky Point and Manomet Point; at effluent, a relatively high value of 398.85 g/m was recorded. Chondrus constituted approximately 50% of the total biomass value at all three stations. The relatively high Chondrus value recorded for g effluent in December was primarily responsible for the high total 5 biomass value recorded for that station. Rocky Point and Manomet Point displayed Chondrus biomass decreases of 38% and 31% respectively between the September, 1979 and December, 1979 collections. (The reduction in totcl algal biomass displayed by both Rocky Point and Manomet Point between the September and December collecting periods is chiefly attributable to decreases in Chondrus ( 58 I'
M M M M M M M M M M m M M M M M M 400 - 400 - 300- 300 - 200 - 200 - M 100 - 100 - E Rocky Point Manomes Point e E lliue n t i Rocky Point Manomet Point E ll t u en t u 3 C hond ru s c rispu s Phyllophora spp. e -
.n a 400 -
E
.9 EC 300 -
700-100 - I I i Rocky Point Manomet Point Elfluent 9/79 12/79 R e mainin g Benthic Species VIGURE 14. Dry weight values (g/m ) for Chondrus crispus, Phyllophora spp. , and the rcmaining benthic species from the ten foot quantitative stations for the September,1979 and December,1979 collecting periods.
I biomass.) Effluent, in contrast, exhibited an extremely sharp 178% increase in Chondrus biomass over the same period. (The increase in total algal biomass shown by effluent between the September and December collections is solely attributable to increased Chondrus biomass.) The pattern of reduced winter Chondrus biomass levels displayed by Rocky Point and Manomet Point reflect the normal seasonal cycle of Chondrus: markedly lowered winter growth rates, coupled with the destructive influences of harsh storms, typically result in a seasonal reduction in the Chondrus population during the winter months. The failure of effluent to exhibit lowered Chondrus biomass values in December is not considered highly unusual. In previous years, g anticipated seasonal fluctuations in biomass have only rarely occurred E simultaneously at all stations. In the 1978 collections, for example, only Manomet Point and effluent showed reductions in Chondrus biomass between the September and December surveys. Comparison of the above data with data from the corresponding collections in 1978 yielded mixed but generally favorable results. The September, 1979 Rocky Point value represents a modest 27% increase over the September, 1978 value; the Manomet Point value represents a small 5% decrease from the September, 1978 value, while the effluent value represents a more substantial decrease of 28%. The December, 1979 Rocky Point value represents a moderate 46% decrease from the previous December, while the effluent value represents a sharp 153% increase; the December, 1979 Manomet Point value was unchanged from the previous December. No extreme changes in Chondrus biomass are indicated in the above comparisons. Effluent, the station showing the widest degree of discrepancy between 1978 and 1979 data sets, has traditionally shown greater short-term fluctuations in biomass than Manomet Point and Rocky Point. 5.4.3 Phyllophora Biomass Phyllophora biomass values for the September, 1979 and December, 1979 collections are included in Table 14 and Figure 14. In September, relatively high and quite similar values of 106.41, 157.14, and 174.90 g/m2 were recorded for Rocky Point, Manomet Point and effluent respectively. The Phyllophora fraction constituted 17% and 21% of the 60 I
I total biomass value at Rocky Point and Manomet Point respectively; at effluent, Phyllophora comprised a somewhat higher 34% of total biomass. In December, similar and again relatively high values of 181.23 and I 172.56 g/m were recorded for Manomet Point and effluent, while a considerably lower value of 81.90 g/m was recorded for Rocky Point. The Phyllophora fraction constituted 17%, 23%, and 32% at Rocky Point, I effluent, and Manomet Point respectively. Rocky Point displayed a 23% decrease in Phyllophora biomass between the September and December collections, while Manomet Point l exhibited a 15% increase; effluent values were unchanged between the two 1 periods. I Values for September and December, 1979 were generally higher than values recorded for the corresponding collections in 1978. September, 1979 values were higher than September, 1978 values at all three stations. December, 1979 values were higher than December, 1978 values at Manomet Point and effluent, but lower than December, 1978 values at Rocky Point. 5.4.4 Biomass of Epiphytic Species Total epiphytic biomass (combined values for epiphytes of Chondrus and epiphytes of Phyllophora data showed an identical pattern among the three sampling stations in both the September, 1979 and December, 1979 collections, Table 14). For both collections, the highest value was I recorded for effluent, the lowest value was recorded by Rocky Point, These I and an intermediate-level value was recorded by Manomet I, int. l l data exhibit a strong positive correlation with the combined biomass values for Chondrus and Phyllophora, the principal host species (the single exception involved effluent, which exhibited the highest combined 1 biomass value for Chondrus and Phyllophora and the lowest combined value I for epiphytic biomass in September, 1979). The observed correlation is considered normal, and simply demonstrates that the extent of the development of the epiphytic population is, in a large part, dependent upon the extent of development of the host species population. Total epiphytic biomass exhibited a moderate decline between the I September, 1979 and December, 1979 surveys at both effluent and Manomet Point; at Rocky Point, epiphytic biomass was essentially unchanged over I 61
I, the two collecting periods. The generally lower December values reflect the normal elimination of many summer annual and pseudo perennial epiphytic species during the winter months. Incluaed in this category is the pseudo perennial Spermothamnion repens, the dominant epiphytic taxa. The Phyllophora epiphytic fraction showed larger biomass values than the Chondrus epiphytic fraction at all stations in both the September, 1979 and December, 1979 collections (Table 14 and Figure 15). This pattern prevailed despite the fact that, with a single exception, Chondrus biomass values consistently exceeded Phyllophora biomass values (the single exception occurred at effluent in September, 1979, when g Phyllophora biomass exceeded Chondrus biomass by a relatively narrow E margin). The apparently greater propensity for epiphytic colonization shown by Phyllophora has also emerged from previous years' data (BECo Report #14), as well as from the current Chondrus/Phyllophora Condition l Index Study (Section 5.4.6). Biomass values for the separate Chondrus and Phyllophora epiphytic fractions are included in Table 14 and Figure 15. The data show that, for September, 1979, biomass values for Chondrus epiphytes ranged from 19.65 (effluent) to 36.76 (Manomet Point) g/m . For December, 1979, values ranged from 14.30 (Manomet Point) to 37.48 (Rocky Point) g/m . Biomass of Phyllophora epiphytes for September, 1979 ranged from 52.55 (Rocky Point) to 155.19 (effluent) g/m . For December, 1979 values 2 ranged from 46.46 (Rocky Point) to 134.01 (effluent) g/m . All three stations showed the anticipated seasonal reductions in Phyllophora epiphytic biomass values between September and December. Only Manomet Point and effluent evidenced declines in Chondrus epiphytic biomass values between September and December; a slight increase in biomas.3 was recorded for Rocky Point. The above data show no appreciable differences in Chondrus or Phyllophora epiphytic biomass between stations. No perturbation related [ to the operation of Pilgrim I is indicated. 5.4.5 Biomass of Remaining Benthic Species l Biomass data for benthic species other than Chondrus and Phyllophora for September, 1979 and December, 1979 collections are 62 I
M M M M M M M M M M M M M M M M M 400 - 400 - 300 - 300 - 200 - 200 - 100 - 100 - i P . N IER e Rocky Point Manomet Point E f fluen t Rocky Point Manomet Point Ef fluent 3 Epiphytes of Chondrus Epiphytes of Phyllophora m
" U 800 -
{ J
!? ,o 400 - -
200 - e j-Rocky Point psnomet Point Ef fluent 9/79 12/79 Total Algal Biomass FIGURE 15. Dry weight values (g/m ) for epipht)tes of Chondrus, epiphytes of Phtl11ophora, and total algal biomass from the ten foot quantitative stations for the September,1979 and December,1979 collecting periods.
I included in Table 14 and Figure 15. The data show that, for September, 2 1979, a relatively high biomass value of 29.28 g/m was recorded for Rocky Point, while moderately lower and very similar values of 21.09 and 20.04 g/m were recorded for effluent and Manomet Point respectively. For December, 1979 a high value of 52.89 was recorded for Rocky Point, and a considerably lower value of 11.49 was recorded for Manomet Point; an intermediate-level value of 25.44 g/m was recorded for effluent. The pattern of reduced winter biomass levels commonly exhibited by Chondrus and the epiphytic species was not in evidence in the above data. Rocky Point exhibited a substantial biomass increase between the September, 1979 and December, 1979 sampling periods, while effluent E exhibited a more modest increase. Only Manomet Point evidenced a E decrease in biomass between the two periods. The September, 1979 and December, 1979 collections mark the first attempt to quantitatively describe the benthic algal population (exclusive of Chondrus and Phyllophora) in the study area. While the I above data were obtained from only two collections, no apparent differences in biomass between the three stations which might be related to the operation of Pilgrim I were in evidence. 5.4.6 Chondrus/Phyllophora Condition index Study The Chondrus and Phyllophora fractions of each replicate subsample were compared with two sets of five standards which showed increasing degrees of plant colonization (epiphytism) or animal colonization (hydrozoan and bryozoan encrustation). Each set of standards was ranked from one to five, in order of increasing colonization. The algal fraction being compared was given the values of the standards it most closely matched in degree of epiphytism and encrustation. Separate
" colonization values" for epiphytism and encrustation were then obtained for each species by adding the values assigned to the three replicate 1
subsamples taken at each site. The separate Chondrus and Phyllophora
" condition index values" refer to the total infastation (epiphytism and encrustation combined) of each species at each station, and were derived by adding together the " colonization values" for animal and plant colonization. A Chondrus/Phyllophora " association condition index" was then derived for each station by adding the " condition index values" for Chondrus and Phyllophora.
64 I
u On both the September, 1979 and December, 1979 collections, higher colonization and condition index values were recorded for Phyllophora than for Chondrus at all stations (Tables 15 and 16). It is theorized that the higher Phyllophora infestation values reflect, at least in part, the greater capability of Phyllophora to tolerate the increased stresses l associated with heavy plant and animal colonization. Morphologically, the wiry Phyllophora is considerably tougher and sturdier than Chondrus.
]
l As a result of its structural superiority, Phyllophora may be able to withstand levels of infestation which, for Chondrus, would be sufficient to bring about dislodgment from the substratum. Higher Phyllophora I colonization and condition index values were also reported for the September, 1978 and December, 1978 collections (BECo Report #14). l l Colonization and condition index values were very similar for Chondrus at all three stations in each of the two collecting periods ! l (Tables 15 and 16). Condition index values ranged from 13 to 15 in September, 1979 and from 8 to 11 in December, 1979. Rocky Point values were very slightly higher than Manomet Point and effluent values in both collections. Colonization and condition index values for P1pllophora I were also quite uniform among the three stations. Condition index values ranged from 21 to 22 in September, and from 18 to 25 in December, 1979. Effluent values were slightly higher than those of Manomet Point and Rocky Point in each of the two collections. The narrow range of values separating stations, together with the absence of clear-cut hierarchical patterns among the three stations, indicates an overall equality of epiphytization and encrr. station levels throughout the study { area. Colonization and condition index values obtained from the corresponding collections in 1978 were genrally lower than current survey values for all stations. However, as in the current collection results, no patterns among the stations were evident, and all values were grouped within a relatively narrow range. Colonization and condition index values for Chondrus showed moderate declines for all stations between the September, 1979 and December, 1979 collections. Phyllophora colonization and condition index values for Rocky Point also showed moderate declines. For effluent and Manomet Point, however, Phyllophora condition index values 65 [ _ - - - -
I I I TABLE 15. Colonization Values for Chondrus crispus and Phy11ophora spp. I from the ten foot quantitative stations for the September, \ 1979 and Dccember,1979 collecting periods. 1 I I ANIMAL COLONIZATION PIANT COLONIZATION l 1 Sept. 1979 Dec. 1979 Sept. 1979 Dec. 1979 Chondrus crispus I Rocky Point 7 5 8 6 I, Effluent 7 6 6 3 Manomet Point 5 4 9 4 Phy11ophora spp. Rocky Point 10 ' 8 12 10 Effluent 11 13 13 12 lbnomet Point 9 10 12 12 l I' I ! Il I, 66 l
- I
- I TABLE 16. Condition Index Values for Chondrus crispus and Phyllophora ll E spp. from the ten foot quantitative stations for the september, 1979 and December, 1979 col 1ecting periods.
lI septenter 1979 December 1979 ! I chondrus crispus Rocky Point 15 11 l
- condition index Effluent 13 9 Manomet Point 14 8
.I Phyllophora spp. Rocky Point 22 18 condition index Effluent 24 25 Manomet Point 21 22 I Chondrus/ Rocky Point 37 29 I Phyllophora condition index Etfluent Manomet Point 37 35 34 30 I I I I I I I 67 \ I
I remained stable over the two periods. This stability was a reflection of a slight increase in animal encrustation values together with a slight decrease in plant epiphytization values. The above pattern typifies a very characteristic response to the change in seasons. The moderately high September values reflect the presence of a large number of heavily encrusted and epiphytized Chondrus and Phyllophora individuals. The lower December values reflect the presence of a higher proportion of stronger, less colonized specimens (the more heavily epiphytized and
- encrusted individuals present in September are more easily dislodged from the substrate during autumn and winter storms). The actual removal 3 of a large number of epiphytic summer annual species is also reflected in the lower December values. Corresponding dr.ta from 1978 also showed an overall decrease in colonization levels between the September and December collecting periods.
Colonization values for Chondrus and Phyllophora obtained from effluent samples were not substantively different from those obtained from Manomet Point and Rocky Point samples for both September, 1979 and December, 1979. No perturbation due to the operation of Pilgrim I was detected. m 5.5 Laminaria Survey Several modifications in experimental design have been introduced since the most recent Laminaria surveys of September, 1978 and June, 1979. Sampling is now entirely non-destructive, with all blade-length measurements and reproductive determinations being perfonced in situ. In addition, a standardized number of ten one-meter square quadrats is now surveyed at each of the three sites. Lastly, the September survey has been eliminated in favor of a January survey in order that sampling might occur during the height of the kelp reproductive cycle. 5.5.1 Laminaria Population Density The density indices used to express Laminaria density patterns were derived from counts of all kelp plants contained within the ten one-meter W square quadrats at each site. Separate density indices were calculated for the total kelp population (Laminaria Population Density Index) and for each of the two kelp species (Laminaria digitata Density Index and L. saccharina Density Index). 68 I
I Data obtained from the January, 1980 survey showed the Manomet Point site to exhibit by far the highest density of Laminaria (both species combined), with a Population Density Index value of 12.1 plant /m (Table 17). Rocky' Point showed a substantially lower index value of 5.0, and the effluent value of 2.4 was the lowest of the three sites surveyed. The low density value recorded for effluent can be at least partly attributed to the relatively small amount of rock substrate available I for kelp colonization in the effluent area. Divers conducting the kelp survey noted that medium to large patches of sand bottom were present throughout the effluent study area, and that portions of these patches were invariably included in the quadrats surveyed. Divers also noted an occasionally heavy deposition of silt and course sand on much of the rock substrate. Sand deposition very likely facilitates abrasion, which ultimately may result in lowered kelp densities. Both the paucity of rock substratum and the presence of siltation at the effluent site have been noted during earlier kelp surveys (BECo Report #12). I No comprehensive comparisons between results of the current and previous surveys will be attempted here as no r ic survey has been conducted during the winter season. However, a cursory examination I shows that results obtained from the most rec ent survey of March,1979 are quite consistent with urrent survey rest its. In both surveys, Rocky Point and effluent showed considerably lower density values than Manomet Point. Moreover, effluent showed the lowest density value in both surveys; and, in each survey, the value shown by effluent was only slightly lower than the value shown by Rock Point. These comparisons, while superficial, nonetheless appear to suggest that kelp density at each of the three sites has remained stable since the most recent survey. 5.5.2 Laminaria Species Density The Manomet Point and effluent sites .ere dominated by Laminaria saccharina, while the Rocky Point site was dominated by L. digitata. The Laminaria saccharina/L. digitata density ratios for Manomet Point, effluent and Rocky Point were 5.1:1, 3.8:1 and 1:2.5 respectively. Manomet Point, with a Laminaria saccharina density index of 10.1 plant /m2 evidenced the highest concentration of this species. l I Effluent ; I 69 l I ;
TABLE 17. Summary of Data generated by the Laminaria Survey of January,1980 ROCKY POINT MNOMET POINT EFFLUENT POPULATION DENSETY AND SPECIES DENSITY L. sac L. dig L. sac L. dig L. sac L. dig Number of M quadrats sampled 10 10 10 10 10 10 Total number of kelp plants counted 14 36 101 20 19 5 Species Density Index ,, (number of plants /m') 1.4 3.6 10.1 2.0 1.9 0.5 Population Density Index (number of plants /m2) 5.0 12.1 2.4 o" Species Density Ratio (L. saccharina : L. digitata) 1: 2.6 5.1 : 1 3.8 : 1 BLADE LENGTH Mean blade length (cm) 67.57 61.31 71.93 77.25 54.95 61.60 I s.d. I21.54 25.37 I34.12 29.31 125.41 22.85 REPRODUCTIVITY Percentage of plants containing sori 66.8 41.6 47.9 48.2 62.6 32.7 m m M M M M M M M M M M M M M _ - -__ M M M M
I and Rocky Points, with density indices of 1.9 and 1.4 respectively, I showed substantially lower concentrations. The highest concentration of Laminaria digitata occurred at Rocky Point, for which a density index value of 3.6 plants /m 2was recorded. Manomet Point and effluent, with density indices of 2.0 and 0.5 respectively, evidenecd lower concentrations. Current data agree only in part with data generated by the most recent survey of March, 1979. In the March, 1979 survey, highest concentrations of Laminarla saccharina were also found to occur at the Manomet Point site, with lower and nearly equal concentrations occurring I at the effluent and Rocky Point sites. Data for L. digitata show less agreement. While current survey results show highest concentrations to occur at Rocky Point, data from the March, 1979 survey shcw Manomet Point to exhibit the highest concentration; in both surveys, however, effluent e.hibited the lowest concentrations. Although the current and most recent surveys were conducted during different seasons, the substantial agreement existing between the two data sets indicates that the densities of both kelp species have remained relatively stable at all three sites. 5.5.3 Laminaria Blade Length The calculated mean blade length of Laminaria saccharina at each site is included in Table 17. The actual blade length measurements are presented as length-frequency histograms in Figure 16. Mean blade lengths of 67.1, 71.9, and 55.0 cm were recorded for Rocky Point, Manomet Point and effluent respectively. Results of a one-way ANOVA showed no significant differences between sites (Table 18). An examination of the length-frequency histograms shows that medium sized blades (50 - 100 cm) were sinilarly well represented at all three sites. Manomet Point I displayed a more balanced distribution of blade size classes than Rocky Point and effluent; both effluent and Rocky Point showed a lack of blades in the larger size classes while Rocky Point showed a lack of blades in l the smallest size classes as well. l The above data are not fully consistent with data generated by the most recent survey of March, 1979. As in the current survey, the March, l 1979 survey revealed no significant differences in blade length between 3
l i 40- M nomes Point Monomet Point N = 101 N=20 I 30-i 20 - -
. 10 - - -- - -
2 l,,- I~ 7 I I I a Rocky Point Rocky Point h 40-y 30- - N:14 N=36 u _ 20 - - c 10 - - I I II l 1 l- I- 1
.$ Ellluent 0-40 - EIIlueni _
30 - N=19 N=5 20 - - -- 10 - i il I i i l i l l l l l 1 I I I I I I II 20 40 60 80 100 120 14 0 160 180 20 40 60 80 100 120 140 160 180 L. Saccharina Blade Length (cm) L. Digitata Blade Length (cm) FIGURE 16. Sizo classes of Laminaria saccharina and L. digitata blade length from the January,1980 survey. M M M M M M M M M M M M M M M M M M M
I I
- I
- I '
TABLE 18. Results of one- way ANOVA comparisons of blade length for l Laminaria saccharina and L. digitata from the January, 1980 survey. I
;I
!I station Level of Comparisons N r-value significance l L. saccharina
- Eff. - M.P. 118 4.25 Not significant
! Eff. - R.P. 31 2.26 Not significant M.P. - R.P. 113 0.22 Not significant l l l L. digitata Eff. - M.P. 23 1.22 Not significant
- Eff. - R.P. 39 0.00 Not significant I
M.P. - R.P. 54 4.54 Not significant lI II !I l I 1 i t 73 l l I
I stations. However, the mean blade length at each site was decidedly larger in the March, 1979 survey. In addition, the effluent site, which showed the lowest mean blade length in the current survey, displayed the highest mean blade length in the March, 1979 survey. The above g inconsistencies may be due in part to the fact that the current and most 5 recent surveys were conducted during dissimilar seasons. The calculated mean blade length of Laminaria digitata at each site is also included in Table 17. Actual blade length measurements are presented as length frequency histograms in Figure 14. Mean blade lengths of 61.3, 77.3, and 61.6 cm were calculated for Rocky Point, Manomet Point and effluent respectively. Results of a one-way ANOVA showed no significant differences between sites (Table 18). An examination of the length-frequency histograms shows medium sized plants (50 - 100 cm) to predominate at all three sites. Rocky Point displayed a substantially more balanced distribution of blade size classes than either Manomet Point or effluent; both Manomet Point and effluent showed deficiencies in the relative proportion of smaller sized blades, and effluent showed an additional deficiency in the number of plants with larger sized blades. These data are not consistent with data derived from the most recent survey of March, 1979. As opposed to the current survey, the March, 1979 survey showed significant differences in blade length to exist between sites. In addition, the mean blade length at the Manomet Point and Rocky Point sites was substantially larger in the >brch, 1979 survey than in the current survey; effluent, in contrast, displayed larger-sized blada lengths in the current survey. As has been stated previously, the fact E 5 that the current and most recent surveys were undertaken during dissimilar seasons is believed to be a contributing factor to discrepancies in results. 5.5.4 Laminaria Reproductivity Results of the January, 1980 survey showed high levels of reproductivity for both Laminaria saccharina and L. digitata at all three sites (Table 17). The highest percentage of reproductive Laminaria saccharina specimens occurred at Rocky Point (66.8%) and the lowest at Manomet Point (47.9%). The highest percentage of reproductive L. digitata occurred at Manomet Point (48.2%), and the lowest at effluent l 74
I 'I (32.7%). All values were generally higher than those recorded from previous surveys. This is believed to be due to the fact that, unlike e the current survey, no previous survey was conducted during the winter season, when kelp reproductivity is at its highest level. Current data show no indication of thermal perturbation at any site. ,a 5.6 Ascophyllum nodosum_Grouth Study ll Initial tagging of Ascophyllum plants and measurement of apices was accomplished in February, 1979 (a detailed description of tagging and measuring procedures is included in the Methods section of this report). Growth rate measurements are to be taken at monthly intervals from March, 1980 through July, 1980. Results will be reported in BECo Report //16. I I I I I I I I I 75 l 1
I
- 6.
SUMMARY
6.1 Faunal Summary 6.1.1 Faunal Systematics Identification of faunal specimens collected during September and December, 1979 resulted in the expansion of the composite faunal species list by 17 new species or categories. Four phyla were involved. Among the ten additions to the phylum Annelida were a previously unidentified capitellid, two sabellids, two terebellids, one pectinariid, one spionid, and a magelonid. The general category Spionidae was used to classify a juvenile specimen. In the polynoid family the species described as Harmothoe imbricata was separated into two species, H. imbricata and H. extenuata. Among the six additions to the phylum Arthropoda were the general catagories Majidae and Cirripedia. Two pycnogonids, one hermit crab, and a parasitic isopod were also discovered and identified to species level. Examination of current and past reference specimens resulted in the name change of one nudibranch and in the identification of another, which was previously listed as species C. Finally a turbellarian, which in past reports was grouped under the general category Platyhelminthes, was identified to the family level. 6.1.2 Faunal Community Descriptions Benthic communities at 10' rock stations have remained basically stable since the beginning of the study in 1974. The environment is very heterogeneous with a diverse assortment of faunal species. As in the past, species composition included members of all major phyla. Although the molluscans Modiolus modiolus and Lacuna vincta were numerical dominants, many arthropods and annelids were also common. 5 Densities of Asterias forbesi were enhanced over recent samplings due to the greater numbers of their prey Nodiolus, which showed recovery from a poor recruitment durf ug 1978. The location of the 20' sand stations allows periodic scouring by the discharge current, resulting in patchy sediment characteristics. Six phyla were represented in the faunal community here, with greatest
- l. 76 l I
l numbers of the haustorid amphipod Protohaustorius delchmannae and the bivalve Tellina agilis. The sand dollar Echinarachnius parma was present, but was considered a dominant in September only. l I 5.1.3 Faunal Community Structure 6.1.3.1 Faunal Species Richness Species richness was consistently greater at rock stations compared to the sand site and was shown to'be significantly greater at Rocky Point over the long-term than at the other two rock sites. All three rock I stations exhibited similar phylogenetic composition and similar composition of " opportunistic families" as well as similar seasonal variation. Richness at the effluent was greatest during September when cold water species would be most impacted by thermal addition. Results, therefore, imply no measurable negative effects #.ich can be directly attributable to the thermal discharge. l 6.1.3.2 Faunal Population Densities Densities of faunal organisms were greatest at rock sites, with mean densities reaching 908,228/m at the effluent. Rock site populations followed densities of Modiolus and to some extent Lacuna vincta. Recovery of Modiolus from a previous poor recruitment was most exaggerated at the effluent, but densities of the mussel, of total populations, t.nd of populations excluding Modiolus agreed well between stations over the short and long-term. I 6.1. 3. *, Densities of Individual Faunal Species Densities of ten common faunal species were tested over short and long-tetrm for differences between stations. Tests for three species were significant, indicating a preference for or reduction at the l effluett site. Enhancement of Caprella penantis densities at tne efflueat coupared to Rocky Point was noted, as were reduced densities of Pleusyntes glaber at the effluent cc' cared to both control sites. These results have been observed previously. Neither species is close to the edge of its temperature range in the Plymouth area and they should not be exhibiting a direct response to the discharge. This leads us to l believe some other interaction is responsible for the observed differences in densities. 77 e
I One species, Margarites umbilicalls, is at the southern limit of I its temperature range and again displayed significantly reduced densities at the effluent site. This gastropod has repeatedly been limited in the discharge area and appeared.to be negatively affected by the thermal addition of Pilgrim Station. Limited standing crop of Laminaria, Margarices' preferred food, at the effluent site may also lower densities of the snail. No serious impact on other coma aity parameters due to lowered Margarites densities has been observed. The species is important primarily as an potential indicator of thermal stress. 6.1.4 Faunal Species Dominance September and December rock sites were dominated by the gastropod Lacuna vincta and the mussel Modiolus modiolus. Modiolus has been the most common rock community dominant throughout this study. Densities of this mussel showed recovery from a previous poor recruitment, particularly in December when densities reached 588,726/m . Co-dominant species included a group of amphipods which have been numerically important since the beginning of the study. The effluent sand site was dominated by the haustorid amphipod Protohaustorius deichmannae and the bivalve Tellina agilis. Co-dominants included several arthropod and annelid species never before considered dominants. This was due to more svenly spread dominance rather than E greater densities of the individual species. Noticeably absent from the 5 dominance hierarchy was the amphipod Acan mohaustorius millsi. 6.1.5 Faunal Community Overlap Community overlap was computed between stations and between replicates of the same station using Jaccard's coefficient of community. l Effluent rock replicate overlap was lowest of all rock stations I suggesting more variability in species composition at this site. Overlap of replicates was only slightly greater than overlap of stations, l suggesting variability between stations is similar to that found between i replicates taken from the same area, Sand station replicates had lowest overlap, indicative of the patchy substrate in the effluent sand area. Analyses comparing station overlap confirm previous results and show greater similarity of species composition between control sites 78 I
I than between the experimental and control sites. This suggests a basic ! difference in community characteristics at the effluent. Furthermore, overlap of present results with results from one year ago also show lower overlap t the effluent site. Therefore, the effluent area appears to be more variable over time and over space, which supports our view of a basic difference in the community in the discharge area compared to control sites. 6.1.6 Faunal Diversity
. Shannon-Wiener diversity and evenness were high at all sites during September, but decreased at rock sites during December. Increased dominance by the mussel Nodlolus in December was responsible as indicated by correlation analyses; diversity was positively correlated with I evenness but not witl. species richness. Both evenness and diversity were negatively correlated with Modlolus densities. When diversity was calculated on non-mussel data only, both diversity and evenness values B were enhanced at stations showing excessive Modlolus dominance, e.g. all December rock stations and the September effluent rock site. Here again the effluent community dominance hierarchy was shown to be slightly different than that at control aites.
Long-term analyses of diversity computed with and without mussels indicates a difference between Rocky Point and the other rock sites. Species richness was significantly greater at Rocky Foint and this factor rather than any difference in evenness, was responsible. Since diversity I at both the control site Manomet Point and the effluent was lower, no thermal effect is implied. 6.1.7 Classification Analysis Substrate characteristics were of primary importance in determining clustering as seen by the initial separation of rock and sand stations. Within the substrate groupings seasonality determined clustering of control stations, whereas effluent sites, for the most part, grouped with inappropriate clusters or separately. Variations in dominance hierarchies at effluent station replicates were believed responsible for the low similarity of these samples. At sand stations, species composition suggests sediment characteristics varied from replicate to I 79 I
I replicate. The low similarity of effluent rock replicates supports our view that the environment in the discharge area is more variable than that found in control sites. This variability appears to be directly related to discharge stress, either thermal or mechanical, on the faunal
~
community. 6.1.8 Faunal Ordination A factor analysis was performed on untransformed combined species frequency data from September and December, 1979. The first three factors accounted for over 97% of the total variance in the data set. Factor 1 showed the separation of stations according to substrate characteristics with sand stations loading separately from rock sites. Factor 2 appeared to differentiate between stations on the basis of densities of annelid species. Scoring of stations on Factor 3 was primarily based on densities of mussel populations, which showed distinct seasonalit.y in the current data. Therefore, loading of all three factors occurred according to both substrate characteristics and seasonality. There was no indication of any difference between control and efflue:.t stations which would imply disturbance of community parameters by the thermal effluent. 6.1.9 Sediment Analysis Grain size analyses performed on sediment cores from the effluent 20' sand site showed moderately to well sorted substrate with modal size classes of .250 mm and .125 mm. Sediment at effluent sites have been characteristically patchy and results from September and December support this view. In past reports localized patchiness was considered the result of periodic scouring by the discharge current, which sweeps away . smaller sediment particles. A recent study, however, indicates the proximity of the sand to rock outcroppings also increases sediment patchiness. This patchiness, in turn, can result in extreme variability in species composition and dominance hierarchies between replicates. Changes in sediment characteristics must therefore be viewed as a localized and sometimes temporary phenomenon which may or may not be representative of the other sand samples. m 30 I
1 1 I i l 6.2 Algal Summary J l 6.2.1 Algal Systematics - I No previously unrecorded algal taxa have been added to the total species list as a consequence of the ana-lysis of the September,1979 and I December, 1979 quantitative algal collections. No taxonomic or nomenclatural changes in the cumulative species list have been made since l the most recent report. 6.2.2 Algal Community Description I The subtidal quantitative survey sites were dominated by Chondrus crispus and Phyllophora spp., with Polyides rotundus, Corallina I officinalis and Ahnfeltla plicata occurring in lesser densities. Laminaria saccharina and L. digitata occurred singly or in dense clusters throughout the survey region. The most conspicuous epiphytes were Spermochamnion repens, Polysiphonia spp. , and Ceramium rubrum. Hildenbrandia rubra Phyriatolithon spp. and Ralfsia spp. dominated the crustose community. 6.2.3 Algal Community Overlap Community overlap values were very consistent in both the September, 1979 and December, 1979 collecting periods. In each period, the highest overlap value was shown by the Rocky Point - Manomet Point pair, while lower and quite similar values were shown by the Rocky Point - effluent and Manomet Point - effluent pairs. All values were higher than those recorded for the corresponding collecting periods in 1978. 6.2.4 Algal Biomass Studies 6.2.4.1 Total Algal Biomass Effluent exhibited lower total algal biomass than >bnomet Point and Rocky Point in the September, 1975 collections, and higher total algal biomass than the two control stations in December, 1979. Manomet Point and Rocky Point displayed the anticipated seasonal reduction in ( total algal biomass between September, 1979 and December, 1979; total biomass at effluent showed a substantial increase between the two periods. Effluent has traditionally shown greater biomass fluctuations than the two control sites, and current survey results appear to be in 81 I
I keeping with this pattern. Total biomass values at effluent for both Septerber, 1979 and December, 1979 represented substantial increases ove. values recorded for the corresponding collecting periods in 1978; values for Manomet Point a'nd Rocky Point were essentially unchanged between the 1978 and 1979 periods. 6.2.4.2 Chondrus Biomass Effluent exhibited lower Chondrus biomass chan Manomet Point and Rocky Point in September, 1979 and highen Chondrus biomass than the two control sites in December, 1979. Manomet Point and Rocky Point displayed the expected seasonal decline in Chondrus biomass between September, 1979 and December, 1979; Chondrus biomass at effluent displayed a substantial increase between the two periods. Chondrus biomass values mirrored, and were primarily responsible for, the total biomass values recorded for each station in both September, 1979 and December, 1979. Effluent has traditionally shown lower Chondrus biomass than Manomet Point and Rocky Point, and has also customarily shown g greater Chondrus biomass fluctuations than the two control sites. Both 5 of these trends were evident in the September, 1979 and December, 1979 data. High current velocity and sedimentation generated by the Pilgrim I discharge are proposed as the primary factors responsible for the anomalous effluent Chondrus data. Biomass values for September, 1979 and December, 1979 were, overall, not excessivly discrepant from values recorded for the corresponding collecting periods in 1978; effluent showed the widest discrepancy between 1978 and 1979 biomass values for both the September and December periods. up 6.2.4.3 Phyllophora Biomass Phyllophora biomass values were lower than Chondrus values at all stations for both the September, 1979 and December, 1979 collections. Effluent, as opposed to Mancmet Point and Rocky Point, displayed relatively high Phyllophora biomass values in both periods. Effluent has traditionally shown higher Phyllophora biomass than the two control l stations. l 82 ' I'
No overall seasonal reduction in Phyllophora biomass was evident between the September, 1979 and December, 1979 samplings. For all stations, September, 1979 and December, 1979 values were higher than those recorded for the corresponding collecting periods in 1978. 6.2.4.4 Biomass of Epiphytic Species For both the September, 1979 and December, 1979 collections, the I highest epiphytic biomass value was recorded by effluent, the lowest value by Rocky Point, and an intermediate-level value by Maaomet Point. The Phyllophora epiphytic fraction exnibited higher biomass values than the Chondrus epiphytic fraction for all stations in both periods, indicating that the Phyllophora population is more heavily epiphytized than the Chondrus population throughout the survey area. Chondrus epiphytic biomass showed considerable variation between stations in both periods; Phyllophora epiphytic biomass was highest at effluent, and lowest at Rocky Point, for both periods. Biomass for both the Chondrus and Phyllophora epiphytic fractions displayed an anticipated decline between the September and December collections. The data disclose no
'I evidence of perturbation by Pilgrim I.
6.2.4.5 Biomass of Remaining Benthic Species Biomass for the remaining benthic species displayed a wide range of I values between stations in both the September, 1979 and December, 1979 collections. Rocky Point displayed the highest biomass in both collections. No pattern of seasonally reduced December biomass was I evident. The September, 1979 and December, 1979 collections mark the first attempt to quantify the benthic population (exclusive of Chondrus and Phyllophora). No perturbation by Pilgrim I is seen in the September, 1979 and December, 1979 data. 6.2.4.6 Chondrus/Phyllophora Condition Index Study Phyllophora showed higher levels of plant and animal colonization than Chondrus at all stations in the September,1979 and December, 1979 collections. It is postulated that Phyllophora is more capable of tolerating the increased stresses associated with heavy plant and animal infestation. 83 I !
I Colonization values for both Chondrus and Phyllophora were generally very similar at all stations for both collecting periods. The narrow range of values separating stations, together with the absence of precise hierarchical patterns among the three stations, indicates an overall equality of epiphytization and encrustation levels throughout the survey area. Colonization values for both Chondrus and Phyllophora showed moderate seasonal reductions in the December collections. The current September, 1979 and December, 1979 values were generally higher than values obtained from the corresponding collecting periods in 1978. 6.2.5 Laminaria Survey 6.2.5.1 Laminaria Population Density Data obtained from the January, 1980 survey showed Manomet Point to exhibit the highest Laminaria density, and effluent the lowest. Reduced rcck substratum at the effluent station, together with the increased sediment lode and current velocity associated with the Pilgrim I discharge, are postulated as the primary factors contributing to the reduced kelp dentm f at effluent. 6.2.5.2 Laminaria Species Density The Manomet Point and effluent sites were dominated by Laminaria saccharina, while the Rocky Point site was dominated by L. digitata. The highest density of L. saccharina occurred at Manomet Point, and the lowest at Rocky Point. The highest density of L. digitata occurred at Rocky Point, and the lowest occurred at effluent. 6.2.5.3 Laminaria Blade Length The highest mean blade length for Laminarla saccharina was recorded at Manomet Point, and the lowest at effluent. The highest mean L. digitata blade length occurred at Manomet Point, and the lowest at Rocky Point. For each species, the mean blade length was relatively similar ! at all st'ations. Size class distributions showed considerable variation among stations for both species. However, medium sized blades were the l dominant size. class at all sites for both Laminaria saccharina and L. digitata. 84 I
l ( i 6.2.5.4 Laminaria Reproductivity Laminaria saccharina and L. digitata both showed high levels cf reproductivity at all stations. The highest percentage of reproductive Laminarla saccharina specimens occurred at Rocky Point, and the lowest , at Manomet Point; highest L. digitata reproductive percentages were found l 1 at Manomet Point, and the lowest at effluent. The data show no evidence of perturbation at any station. 6.2.6 Ascophyllum nodosum Grouth Study Initial tagging and measurements of Ascophyllum plants was performed in February, 1979 and the Manomet Point, Rocky Point and efflusnt stations. Growth rate measurements will be taken at monthly intervals from March, 1)80 through July, 1980. Results will be included in BECo Report #16. I l I l 85 ' !I
LITERATURE CITED Boston Edison Co. 1978. Marine ecology studies related to operation of Pilgrim Station. Semi-Annual Report 12. 1979. Marine ecology studies related to operation of Pilgrim Station. Semi-Annual Report 13. 1979. Marine ecology studies related to operation of Pilgrim Station. Semi-Annual Report 14. 1980. Assessment of near-field impacts of Pilgrim Nuclear Power Station thermal discharge on marine benthic communities and the gastropod Margarites umbilicalls. Bousfield, E.L. 1973. Shallow-water gammaridean amphipoda of New England. Cornell University Press, Ithaca, New York. 312p. Connell, J.H., and Orias, E. 1964. The ecological regulation of species diversity. The American Naturalist. Volume 98, Number 903:399-414. Grassle, J.F., and Grassle, J.P. 1974. Opportunistic life histories and genetic systems in marine benthic polychaetes. Journal of Marine Research. Volume 32, Number 2:253-284. Greig-Smith, P. 1964. Quantitative plant ecology. 2nd Ed. Butterworths, Washington. 265p. Logan, D.T., and Maurer, D. 1975. Diversity of marine invertebrates in a thermal effluent. Journal Water Pollution Control Federation. I Volume 47, Number 3:515-523. Lubchenco, J., and Menge, B.A. 1978. Community development and persistence in a low rocky intertidal zone. Ecological Monographs. Volume 48, Number 1:67-94. Luders, G., and Olinski, P.J. 1976. Analysis of environmental data and alternate discharge limits. Report to New England Power Service Company, Westborough, Mass. The Analytic Sciences Corporation. Reading, Mass. Section 5:21p. McCain, J.C. 1968. The caprellidae (Crustacea: amphipoda) of the Western North Atlantic. United States National Museum bulletin. Number 278:147p. Mendenhall, W. 1975. Introduction to probability and statistics. 4th Ed. Duxbury Press. Belmont, California. 459p. Morris, P.A. 1973. A field guide to shells of the Atlantic and Gulf I,l Coasts and the West Indies. The Peterson Field Guide Series. 330p. 1 86 l l l
I LITERATURE CITED (continued) Parke, M., and Dixon, P. 1976. Checklist of British marine algae. 3rd revision. Journal of the Marine Biological Association of the United Kingdom. 56:527-594. Pettibone, M.H. 1963. Marine Polychaete worms of the New England region. 1. Families Aphrodicidae through Trochochaetidae. 356p. Simpson, G.G. 1964. Species density of North American recent mammals. Supt. Zool. 13:57-73. South, C.R. 1976. A checklist of marine algae of Eastern Canada. 1st revision. Journal of the Marine Biological Association of the United Kingdom. 56:817-843. Taylor, W.R.T. 1957. Marine algae of the northeastern coast of North America. 2nd Ed. University of Michigan Press. Ann Arbor, MI. 509p. Wass, M.L. 1967. Biological and physiological basis of indicator l organisms and communities. Section II. Indicators of pollution ,
- p. 271-284. In T.A. Olson and F.J. Burgess ed. Polution and l Marine Ecology. John Wiley & Sons, New York. )
l l I I . l l 87 J
APPEND 1X 1. Faunal species list (numbers .per square meter) for September,1979. RP 10* ER 10* MP 10
- ES 20*
COELENTERATA . Anenome C6 6 Campanularia spp. C4 Cerianthus amcricanus C9 Coelenterata (medusa) C8 Edwardsia sipunculoidca C13 Edwardsia elegans C10 Haliclystus auricula C12 Haliclystus salpinx C7 31 55 18 m nctridium senile C15 165 Obolia spp. CS Sagartia modesta C14 Sartularia pumila C1 P Sertularc11a rugosa C3 Y P P Thularia argentca C2 P P P Unidentified Coelomate UC 147 67 337 PLATYHEllf1NTl!ES PLAT 18 nonoophorum spp. PL1 5 NDfERTEA Amphiporus caecus ND16 Cerebratulus lactcus ND13 Lineus bicolor NDI4 Lineus app. NDIS Tetrastcmma candidum ND11 Tubu1 anus pollucidus NDt2 PORIFERA P P P W W
m m m M M M M APPENDIX 1 (continued) RP 10* ER 10* MP 10' ES 20'
~
ANNELIDA Aglaophamus circinata P48 Amastigos n.sp. P416 6 5 Ampharete acutifrans P94 Ampharete arctica P58 Amphitrite johnstoni P422 Amphitrite ornata P310 Arenicola marina P302 Aricidea Jeffreysii P21 Asabellides oculat, P35 37 141 104 Autolytus cornutus P87 6
$ Autolytus emortoni P99 Autolytus fasciatus P405 Autolytus prismaticus P10 24 Autolytus spp. P71 Autosyllis spp. P12 Brania clavata P47 Capite11a capitata P31 6 6 55 Chactozone setosa P30 Chone spp. P417 6 Cirratulus cirratus P29 6 Cirratalus grandis P112 Clymene11a torquata P32 Dorvilleidae P17 Dodecaceria coralii P28 Eteone heteropoda P92 Etcono longa P9 Euchone rubrocinta P73 Eulalia viridis P8 43 692 214 Eumida sanguinea P63
I t l APPENDIX 1 (continued) l RP 10' ER 10* MP 10 ' ES 20' t ANNELIDA (continued) . Eusyllis bloomstrandi P77 Eusy11is lamelligcra P305 Exogone hebcs P301 Flabelligera affinis P70 Frabricia sabella P39 Glycora americana P75 Glycera capitata P403 Glycera dibranchiata P97 Goniadella gracilis P74 Narmothoc extenuata P414 18 6 37 Narmothoo imbricata P2 141 171 410 c) Ichthyobel11dae P1 Laonome kroyori P423 Lcpidanotus squamatus P3 98 220 275 Lumbrinereis brevipes P57 Lumbrincrois fragilis P313 Magelonidae P96 Magelonidac rosca P419 Maldanidae PS5 Mediomastus ambiseta PK3 Microphthalmus aberrans PS2 Minuspio spp. P69 Myriochele hocri P88 Naineris quadricuspida P18 Nephtys bucera P15 Nephtys caeca P16 6 330 Nephtys incisa P101 Nephtys picta P62 Norois grayi P61 Noreis pelagica F14 135 404 1126
APPENDIX 1 (continued) RP 10' ER 10' MP 10' ES 20' ANNELIDA (continued) - Narcis succinea P110 Nerinades agilis P91 Nicolea venustula P36 104 37 961 Nicomache lumbicalis P33 Ninoo nigripes P89 011gochaeta P43 24 24 Orbinia ornata P60 Orbinia swani P50 Orbiniidae P308 Owcnia fusiforuds P56 w Paraonis fulgens P51 11 Paraonis gracilis P303 Paraprionosyllis longicirrata P404 Pectinaria gouldil P34 73 Pectinaria granulata P415 49 Peloscolex bonodoni P407 Pherusa affinis P54 Pholoo minuta P4 12 802 257 5 Phy110doce arenao P7 101 Phyllodoce maculata P6 86 600 122 32 Phyllodoce mucosa P46 12 6 21 Phyllodoce spp. P105 Pista maculata P37 Polychaeta spp. P100 Polychaete sp. A P309 Polycirrus cximus P315 Polycirrus spp. P307 Polydora ciliata P314 Polydora socialis P420
APPENDIX 1 (continued) RP 10' ER 10* MP 10' ES 20' ANNELIDA (continued) Polydora ligni P23 Polydora spp. P25 Polydora websteri P24 Potamothus spp. P104 Potamilla remiformis PLO 37 Potamilla oculifera P103 Prax 111c11a praetelndssa P55 Prionospio stroenstrupi P53 Pygospio clogans P79 Rhodine spp. P80
$ Saba11 aria vulgaris P13 Scolocolepides viridis P67 Scale 1cpis squamata P22 Scoloplos acutus P66 Scolaplos armiger P20 Scoloplos fragilis P19 Scoloplos riscri P68 Scoloplos robustus P93 Scoloplos spp. P64 Spio filicornic P98 Spionidae P424 Spiophanos bombyx V52 149 Spirorbis Lorcalls P41 P P P Spironois spirillun P42 P P P Stauronarcis caecus P49 Sthenelais boa E5 Sthenelais linicola P45 Stroblospio benedicti P26 Streptosyllis varians P90 Sy111daa P81 49 m m -
m M M M
W M M M M M M M M M M M M M APPENDIX 1 (continued) RP 10' ER 10' MP 10 ' ES 20' ANNELIDA (continued) - Sullides longicirrata P406 6 Syllides verilli P11 Syllis cornuta P76 Syllis gracilis P306 Tharyx acutus P27 49 53 Terebellidae P38 6 Trichobronchus app. P421 Tubificidae P408 e ARCIIIANNELIDA ARCil 104 w MOLLUSCA Acmaca rubella M304 Acmaca testudinalis M3 86 12 43 Aeolidia papillosa M41 6 306 110 Acquipecten itradians M63 A1vania areolata M20 422 A1vania castanca M21 Anadora transversa M59 Anomia aculeata M37 6 6 Anomia simplex M36 24 43 12 Assiminea succinea M54 Bivalvia sp. A M48 Bivalvia sp. B M62 Bivalvia spp. M86 Calliostoma occidentalc M15 Capulacmaea radiata M43 Capulus unguricus M58 Cerastoderma pinnulatum M31 282 67 337 5 Colus spp. M27
APPENDIX 1 (continued) RP 10' ER 10* MP 10' ES 20' HOLLUSCA (continued)
- Crepidula fornicata M4 6 6 Crepidula plana M85 6 73 12 Cropidula app. MS Dendronotus frandosus M66 6 Diaphana minuta M19 110 80 263 Doto coronata M65 Ensis directus M49 21 Eubranchus exiguus M29 Facelina hostoniensis M307 12 18 24 e Gastropoda spp. M83
- Gastropoda sp. A M28 Gemma gemma , M306 18 filatella arctica M32 979 4480 Idulia cornata M60 Ischnochiton ruber M1 Lacuna vincta M10 20019 11457 41206 Lepeta caeca M2 12 43 Littorina littorca M6 Littorina obtusata M7 Littorina saxatilis M303 Lunatia heros M22 Lyonsia hyalina M44 Macoma halthica M38 Macoma calcarea M302 Maconu tenta M52 Margarites coastalis M12 Margarites umbilicalis M9 4431 208 4676 Mitrolla lunata M11 6 24 Modiolus modiolus M53 10367 11799 24615 11 m m m m M M M M M M M
W M M M M M M M M M M M M APPENDIX 1 (continued) . RP 10' ER 10' MP 10* ES 20' . MOLLUSCA (continued) Mya arenaria M35 Mytilus edulis M30 trassarius obtusata M25 Nassarius trivittatus M24 59 Neptunca despecta tornata M67 Nucella lapillus M8 Nucula delphinodonta 115 0 12 16 Nucula tenuis M305 Nucula spp. M84 Nudibranchia sp. D M64 6 8 Odostoala bartschi M16 6 Odostomia seminada M17 odostomia spp. M82 Oenopota turricula M46 Omaloggra atomus M26 6 6 Onchidoris aspora M40 1255 1138 2111 Onoba aculeus M18 649 55 692 Pandora gouldiana M47 Petricola phaladiformis 113 9 18 , Placopectin magellanicus M45 Retusa obtusa M23 Siliqua costata M51 6 Spisula solidissima M33 12 6 53 Tellina agilis ! 34 257 129 1199 Thracia septentrionalis ?.300 Turbonilla ateolata M13 6 Turbonilla elegantula M56 12 Turbon1112 polita M14 Turbonilla spp. !!81 Velutina laevigata M57
APPENDIX 1 (continued) RP 10' ER 10' MP 10
- ES 20*
ARTilROPODA Acanthohaustorius millsi A22 53 Achelia scabra A111 6 Ache 11a spirosa A34 24 Aeginina longicornis A23 4413 1016 3017 Amraathea acheliodes A129 12 Amphipoda A112 Amphithoe rubricata A9 2081 3084 3207 Anomura A27 Anonyx lilljeborgi A76 Anonyx sarsi A58 Anoplodacty1us lentus A31 18 l Anoplodactylus petiolatus A32 I $ Balanus,balanoides A1
- Balanus balanus A109 Balanus crenatus A2 Balanus aburneus A75 Balanus improvisus A104 Bathyporeia spp. A81
\ l Brachyopoda larvae A108 l Brachyura larvae A28 12 Calathura branchiata A48 Calliopius laeviosculus A10 2301 624 1518 Cancer borealis A100 6 Cancer irroratus A29 31 349 141 5 Caprella penantis A24 7197 8182 9700 43 Carcinus maenus A35 Caridea A25 Chiridotea caeca A41 Chiridatea tuftsi A40 69 ! Cirolana concharum A63 5 m m m m m m M M m m W m m m m m m y
T r uma e m m m m m m m g g g g g g g g g APPENDIX 1 (continued) RP 10* ER 10* MP 10* ES 20' ARTIIROPODA (continued) . Cirolana polita A44 Cirripedia A90 12 21 Corophium acucum All 2901 918 2632 Cotophium bonelli A12 526 3146 1432 Crangon septcmspinosus A46 Crustacea larvae A107 Cyathura polita A80 Cyclaspis varians A37 Dexamine thea A13 5263 5251 7026 Diastylls polita A4 12 86 139 Diasty11s quadrispinosus A36 e Diastylis sculpta AS 12 Diastylis spp. A69 Edotca montosa A43 Edotca triloba A42 512 Erichthonius brasiliensis A79 Eualus pusiolus A26 330 171 392 Eudore11opsis deformis A14 Eudrodolla cmarginata A39 Gananarus spp. A21 Haustorius canadensis A70 Hippomedon scrratus A49 Hyalc nilsono A14 Hyas coarctatus A30 6 Idotea Lalthica A7 135 135 6 Idotea phosphorea A6 1322 2424 1903 5 Ischyrocerus anguipos A15 10477 1518 5912 Isopoda A64 Jacra marina A8
APPENDIX 1 (continued) RP 10' ER 10' MP 10* ES 20' ARTHROPODA (continued) . Jassa falcata A16 10049 7454 16316 5 Lamprops quadriplicata A67 12 16 Leptochelia savignyi A45 Leptocuma minor A65 43 Maera spp. A68 Majidae A135 6 Marinogammarus stoerensis A103 Metope11a angusta A20 Microdcutopus gry110talpa A19 Monoculodes edwardsii A71 Monoculodes tesselatus A60
$ Mysidacea A89 Neomysis americana A85 Nymphon grossipes A133 6 31 Nymphon stromli A91 Orchomonella minuta A116 Orchomonella pinguis A117 12 Ostracoda A3 367 1726 796 Oxyurostylis smithi A38 16 Pagurus acadians A86 12 Pagurus arcuatus A132 12 Pagurus longicarpus A47 12 5 Parophaxus epistomus A62 Parophoxus spinosus A53 Pella mutica A87 1 Photis macrocoxa A55 32 Photis theinhardi A137 Phoxichylidium femoratum A131 6 18 12 Phoxocephalus halbolli A50 12 110 M M M M M M M M M M M M M M M M M M l
m m~ M-m m m-m m m m m m m m m m m APPENDIX 1 (continued) RP 10' ER 10* MP 10 ' ES 20' ARTHROPODA (continued) . Phryxus abdominalis A136 Pleusymtes glabor A17 6573 2950 10588 Pontogensia inermis A18 2534 1787 2362 Proboloides holmesi A115 220 12 135 Protohaustorias dolchmannae A51 12 1759 Protohaustorius longimerus A61 Psammonyx nobilis A118 16 Pseudohaus torius caroliniensis A77 Pseudunciola obliquua A52 e Ptilanthura tenuis A88 Stegophryxus hyptius A66 Synchc11dium americanum A119 Tangstylum orbiculare A33 Tmetonyx nobilis A56 43 Trichophaxus epistomus A57 Unciola irrorata AS4 16 SIPUNCULOIDEA S1PU ECil1NUDERMATA Amphipholis squamata E4 98 318 Asterias forbesi El 184 245 667 Cucumaria frondosa E9 18 Echinarachnius parma E8 112 Henricia sanguinolenta E2 6 6 llolothurlodea E7 Leptosynapta tenuis E10 Ophiopholis aculeata E3 1053 490 1738
i APPEND 1X 1 (continued) . RP 10' ER 10' MP 10' ES 20' ECilINODEIU1ATA (continued) Strongylocentrotus drochbachiensis E6 655 165 667 Ophluroldea Ell 6 Cil0RDATA Amaroucium conste11atum Cll4 Ascidiacea (ccionial) P P p Ascidiacea (solitary) CII2 80 43 612 Boltenia echinata Cll3 Botryllus scholosseri Clll g Mogula app. ClI6 Phoronis architecta Cll5 PISCES
- PISC ECTOPROCTA Boucrhankia gracilis P P Bugula turrita P P P Callopora aurita P P P Callopora craticula P lmilopora lincata callopara punctata P Cau1oramphus cymbacformis Cribrilina annulata P Cribrilina punctata P crisia churnea P P P Cryptostoma pa11asiana Dendrobeania inurtayana P P P m m e m e e e e m W W W M M M M M M M
APPENDIX 1 (continued) . RP 10' ER 10' MP 10' ES 20* i i
- ECTOPROCTA (continued)
Disporella hispida P P P Electra crustulenta Electra pilosa P P P Eucratea loricata Haplota clavata P P P Hippothoa hyalina P P P Lepralia pa11asiana P Parasmittira trispinosa Pore 11a proboscidea e Schizoporella unicornis P w Tubu11pora lillacca P P P Umbonula arctica
+
i I
APPENDIX 2. Faunal species list (numbers
- Per square meter) for December, 1979.
RP 10' ER 10' hP 10' ES 20' COELENTERATA . Anenome C6 55 Campanularia spp. C4 Cerianthus americanus C9 Coelenterata (medusa) C8 Edwardsia sipunculoidea C13 Edwardsia elegans C10 Haliclystus auricula C12 Hallclystus salpinx C7 6 12 Metridium senile C15 g obelia spp. C5 8 Sagartia modesta C14 Sertularia pumila C1 P Sertulatella rugosa C3 P P P Thuiaria argentea C2 P P Unidentified Coelomate UC 43 159 PLATYHE114INTilES PLAT 5 Monoophorum spp. PL1 NDIERTEA Amphiporus caccus ND16 Cerebratulus lacteus ND13 NDf4
- Lineus bicolor Linous spp. ND6 Tettastemma candidum NDIL Tubulanus pollucidus NDi2 PORIFERA P P W W M M M M M M M M M M M M M M M M M
APPENDIX 2 (continued) - RP 10' ER 10' MP 10' ES 20' ANNELIDA Aglaophamus circinata P48 Amas tigos n. sp. P416 Ampharate acutifrons P94 Ampharcto arctica P58 Amphitrito johnstoni P422 6 Amphitrito ornata P310 Arenicola marina P302 Aricidea jeffreysil P21 6 Asabellides oculata P35 12 12 24 Autolytus cornutus P87 24 6 e Autolytus emertoni P99 El Autolytus fasciatus P405 Autolytus prismaticus P10 Autolytus spp. P71 Autosyllis spp. P12 Brania clavata P47 Capite11a capitata P31 31 5 Chaetozone setosa P30 Chone spp. P417 Cirratulus cirratus P29 12 6 122 5 Cirratulus grandis P112 Clymene11a torquata P32 Dorvilleidae P17 Dodecaceria coralii P28 18 6 Eteone hotaropoda P92 6 Etcono longa P9 Euchono rubrocinta P73 Eulalia viridis PS 92 73 263 Eumida sanguinea P63
APPENDIX 2 (continued) . RP 10' ER 10' MP 10' ES 20' ANhELIDA (continued) . Eusy11is bloomstrandi P77 Eusy111s lame 111gora P305 Exogone habes P30L Flabc111gera affinis P70 Frabricia sabella P39 Glycera americana P75 clycora capitata P403 Glyccra dibzanchiata P97 Goniadella gracilis P74 Narmothoe extenuata P414 135 282 239 g, Narmothoe imbricata P2 49 31 12 g Ichthyobellidae P1 Laonomo kroycri P423 6 Lepidonotus squamatus P3 55 37 55 Lumbrinerals brevipes P57 Lumbrincreis fragilis P313 Magelonidae P96 Magelonidae rosea P419 6 tbidanidae P85 Mediomastus ambiseta P83 Microphthalmus abctrans P82 Ninuspio spp. P69 Mtriochele j heari P88 Naincris quadricuspida P18 Nephtys buccra P15 Nephtys cacca P16 330 Nephtys incisa P101 Nephtys picta P62 Nerois grayi P61 Norcis pelagica P14 190 477 337 m M M M M M M M M M M M M M M __ _ _ _ M___ f_]
APPENDIX 2 (continued) . RP 10' ER 10' MP 10' ES 20' ANNELIDA (continued) - Nereis succinea P110 Herinades agilis P91 Nicolea venustula P36 220 18 1034 Nicomacho lumbicalls P33 Ninoe nigripes P89 011gochaeta P43 orbinia ornata P60 Orbinia swani P50 Orbiniidae P308 owenia fusiformis P56 w Paraonis fulgens P51 11 8 Paraonis gracilis P303 Paraprionosyllis longicirrata P404 Pectinaria gouldii P34 Pcctinaria granulata P415 Peloscolex benadoni P407 Phcrusa affinis P54 Pholoe minuta P4 135 239 67 Phy11odoce arenac P7 Phyllodoca maculata P6 18 98 61 107 Phyllodoce mucosa P46 12 21 Phyllodoce spp. P105 Fista maculata P37 Polychaeta spp. P100 Polychaete sp. A P309 Polycirrus eximus P315 Polycirrus spp. P307 Polydora ciliata P314 Polydora socialis P420 12 6 m _ _ _ _
APPENDIX 2 (continued) RP 10' ER 10' MP 10' ES 20' ANNELIDA (continued) Polydora ligni P23 Polydora spp. P25 Polydora websteri P24 Potamethus spp. P104 Potamilla remiformis P40 Potamilla oculifera P103 Fraxillella praetermissa P55 Prionospio streenstrupi P53 Pygospio elegans P79 Rhodine spp. P80 y sabellaria vulgaris P13 6
- Scolocalepidos viridis P67 Scalcicpis squamata P22 Scoloplo9 acutus P66 Scoloplos armiger P20 Scolopics fragilis P19 Scoloplos riscri PG8 Scoloplos robustus P93 Scoloplos spp. P64 Spio filicornis P98 Spionidae P424 6 Spiophanes bombyx PS2 6 1210 Spirorbis borealis P41 P P p Spitorbis spirillum P42 P P y Stauroncreis caecus P49 Sthenciais boa PS Sthenoli:is limicola P45 16 Streblospio bcnedicti P26 5 Streptosyllis varians P90 Syllidae P81 m m m m m m m M M M M M M M M M M M M
M M M M M M M M M M M M M M M M
~
APPENDIX 2 (continued) RP 10' ER 10' MP 10' ES 20' ANNELIDA (continued) - Sy111dcs longicirrata P406 Syllides verilli ?11 Syllis cornuta P76 Syllis gracilis P306 Tharyx acutus P27 6 501 Terebellidae P38 Trichobronchus spp. P421 6 Tubificidae P408 k ARCliIANNELIDA ARCll 12 12 314 MOLLUSCA Acmaca rubella M304 Acmaca testudinalis M3 6 6 24 Aeolidia papillosa M41 122 24 Acquipecten irradians M63 A1vania arcolata M20 6 6 A1vania castanca M21 Anadora transversa M59 Anomia aculeata M37 6 Anomia simplex M36 92 98 Assiminea succinea M54 Bivalvia sp. A M48 Bivalvia sp. B !!62 Bivalvia spp. M86 Calliostoma occidentale M15 Capulacmaca radiata M43 Capulus unguricus M58 Corastoderma pinnulatum M31 129 275 5 Colus spp. M27
APPENDIX 2 (continued) -
~
RP 10' ER 10* MP 10 ' ES 20' MOLLUSCA (continued) - Crepidula fornicata M4 Crepidula plana M85 Crepidula spp. M5 Dendronotus frondosus M66 6 Diaphana minuta M19 37 12 49 Dato coronata M65 6 Ensis directus M49 11 Eubranchus oxiguus M29 6 Facelina bostoniensis M307 30 43 g Castropoda spp. M83 g Castropoda sp. A M28 Gemma gemma M306 niaeella aretica M32 159 67 667 Idulia cornata M60 Ischnochiton rubar M1 Lacuna vincta M10 7962 1304 7803 5 Lepeta cacca M2 12 Littorina littorca M6 Littorina obtusata M7 Littorina saxatilis M303 Lunatia heros M22 27 Lyonsia hyalina M44 nacoma balthica M38 nacoma calcarea M302 Macoma tenta M52 Margarites coastalis M12 Margarites umbilicalis M9 1261 37 734 Mitre 11a lunata Mll 37 12 18 5 Modiolus modiolus M53 98177 588726 102320 821
7 ..- n n n n n n _n n n _n n M .R R R R _R_ P I
~
APPENDIX 2 (continued) _ RP 10' ER 10' MP 10 ' ES 20' MOI.LUSCA (continued) Mya arenaria M35 Mytilus edulis M30 Nassarius obtusata M25 Nassarius trivittatus M24 80 Neptunca despecta tornata M67 Nucella lapillus M8 Nucula delphinodonta M50 6 27 Nucula tenuis M305 Nucula spp. M84 Nudibranchia sp. D M64 H Odostomia bartschi M16 12 S Odostomia seminada M17 Odostomia spp. M82 Oenopota turricula M46 Omalogyra atomus M26 61 Onchidoris aspera M40 214 539 759 Oniba aculeus M18 282 6 588 Pandora gouldiana M47 Petricola phaladiformis M39 6 37 Placopectin magellanicus M45 49 Retusa obtusa M23 Siliqua costata M51 Spisula solidissima M33 37 6 378 Tellina agilis M34 24 12 1972 Thracia septentrionalis M300 6 Turbonilla areolata M13 Turbanilla elegantula M56 6 43 Turbanilla polita M14 Turbanilla spp. M81 volutina laevigata M57
i APPENDIX 2 (continued) - RP 10* ER 10' MP 10* ES 20' ARTIIROPODA - Acanthahaustorius cdllsi A22 85 Ache 11a scabra A111 Ache?lt spinosa A34 12 Aeginana lo . .gicornis A23 643 459 759 Amnothea acheliodes A129 Amphipoda A112 Amphithoe rubricata A9 649 1530 404 5 Anomura A27 Anonyx lilljeborgi A76 w Anonyx sarsi A58 h; Anoplodactylus lentus A31 Anoplodactylus petiolatus A32 Balanus balanoides Al Balanus balanus A109 Balanus crenatus A2 Balanus churneus A75 Balanus improvisus A104 Bathyporcia spp. A81 Brachyopoda larvae A108 Brachyura larvae A28 Calathura branchiata A48 Calliopius laeviosculus A10 61 269 37 Cancer borealis A100 Cancer irroratus A29 18 80 49 11 Capre11a penantis A24 5985 7748 1573 Carcinus caenus A35 Cariden A25 Chiridotea caeca A41 6 Chiridotea tuftsi A40 59 Cirolana concharum A63 m M M M M M M M M M M M M M M M M M
M M M M M M m m m m m m M M M M m APPENDIX 2 (continued) . RP 10' ER 10* MP 10 ' ES 20' ARTHROPODA (continued) . Cirolana polita A44 Cirripedia A90 Corophium acutum A11 2889 4076 3146 Corophium bonelli A12 4419 11885 967 11 Crangon septomspinosus A46 Crustacea larvae A107 Cyathura polita A80 , Cyclaspis varians A37 27 Dexamine thea A13 7087 3709 2448 Diastylis polita A4 6 6 85 w Diastylis quadrispinosus A36 Y Diastylis sculpta A5 Diastylis spp. A69 Edotea montosa A43 Edotea triloba A42 6 267 Erichthonius brasiliensis A79 Eualus pasiolus A26 92 147 269 Eudore110psis deformis A74 Eudrodolla emarginata A39 . Gammarus spp. A21 Haustorius canadensis A70 Hippomedon serratus A49 Hyale nilsono A14 Hyas coarctatus A30 6 Idotea halthica A7 49 135 6
. Idotea phosphorca A6 496 1034 624 Ischyrocerns angulpes A15 4761 13452 5251 Isopoda A64 Jacra marina A8
APPENDIX 2 (continued) - RP 10' ER 10' MP 10' ES 20' ARTHROPODA (continued) . Jassa falcata A16 8238 13231 11836 11 Lamprops quadriplicata A67 16 Leptochella savignyi A45 Leptocuma minor A65 5 Macra spp. A68 Maj idae A135 Marinogamnarus stoerensis A103 Metope11a angusta A20 Microdeutopus gry110talpa A19 Monoculodes edwardsii All Monoculodes tesselatus A60 [ Mysidacea A89
" neomysis americana A85 Nymphon grossipes A133 6 Hymphon stromii A91 Orchononella minuta A116 12 Orchomonella pinguis A117 12 Ostracoda A3 312 1224 942 107 Oxyurostylis smithi A38 Pagurus acadians A86 1 Page::us arcuatus A132 6 Pagurus longicarpus A47 Parophoxus epistomus A62 Parophoxus spinosus A53 Pelia mutica A87 Photis macrocoxa A55 24 426 Photis rheinhardi A137 12 l Phoxichylidium femoratum A131 6 Phoxocephalus halbolli A50 12 24 l
l
APPENDIX 2 (continued) - RP 10' ER 10' MP 10' ES 20' ARTIIROPODA (continued) . Phryrus abdominalis A136 6 Pleusymtes glabor A17 1652 4419 7417 5 Pontogeneia inermis A18 1756 2791 2583 Proboloides holmesi A115 171 636 796 Protohaustorius deichmannae A51 5415 Protohaustorius longimerus A61 Psammonyx nobilis A118 128 Pseudobaustorius caroliniensis A77 Pseudunciola obliquua A52 y Ptilanthura tenuis A88 u Stegophryxus hyptius A66 Synchelldium ancricanum A119 Tanystylum orbiculara A33 Tmetonyx nobilis A56 80 Trichophoxus epistomus A57 5 Unciola irrorata AS4 11 SIPUNCULOIDEA SIPU ECllINODERMATA Amphipholis squamata E4 86 55 135 Asterias forbesi El 214 422 147 Cucumaria frondosa E9 Echinatachnius parma E8 256 Henricia sanguinolenta E2 6 31 llolothuriodea E7 Leptosynapta tenuis E10 11 Ophiopholis aculeata E3 1102 1010 1738 5
APPENDIX 2 (continued) RP 10' ER 10* MP 10 ' ES 20' ECllIN0DERMATA (continued) Strongylocentrotus drochbachiensis E6 251 80 551 Ophiuroidea Ell C110RDATA Amaroucium conste11atum Cll4 Ascidiacea (colonial) P P Ascidiscea (solitary) Cll2 55 24 104 Boltenia echinata Cll3 Botryllus scholosseri Clli P g Nogula app. Cll6 Photonis architecta Cll5 PISCES PISC ECTOPROCTA Bowerbankia gracilis P P Bugula turrita Callopora aurita P P P Callopora craticula Callopora lineata Callopora punctata Cau1oramphus cymbacformis Cribrilina annulata Cribrilina punctata P P P Crisia eburnea P P P P Cryptostoma pa11asiana Dendroboania murrayana P P W W W W W W W W W W M M M M M M M M
M M m M M M m e m m m m e e APPENDIX 2 (continued) - t RP 10' ER 10' MP 10' ES 20'
~
l ECTOPROCTA (continued) Disporella hispida P P P Electra crustulenta Electta pilosa 2 y y Eucratca loricata Haplota clavata P P P Hippothoa hyalina ? P P Lepralia pa11asiana parasaittira tvisp1nosa Fore 11a proboscidea schizoporella unicctnis P g Tubu11pora liliacca P P y Umbonula arctica 4 4 l 4 i 8 O I
APPENDIX 3. Algal species recorded from the ten foot quantitative stations for the September,1979 and December,1979 collecting periods. The relative abundance of each species in each replicate sample is indicated. September 1979 December 1979 Manonet Point ' Rocky Point Effluent Manomet Point Rocky Point Effluent 1 2 3 1 2 3 1 2 3 1 2 3 1 2 3 1 2 3 CHEDROPHYTA Bryopsis plumosa Chaetomorpha linum 0 R 0 0 C C R 0 C R 0 0 A 0 C 0 C R C. melagonium R R R R 0 0 R 0 0 R 0 0 0 0 R R 0 R Enteromorpha flexuosa R R R 0 0 0 Rhizoclonium riparium R 0 0 R R 0 R R R R R R R R R Ulva lactuca R R R R 0 0 C R R C R R R PHABOPHYTA Chordaria flagelliformis Desmarestia aculeata R 0 R R R R R R R 0 0 R R h R D. viridis Laminaria digitata L. saccharina R R R Sphacelaria cirrosa R 0 0 0 R R 0 R R R R RHODOPHYTA Ahnfeltia plicata R R R R R R 0 R 0 0 R C R Antithamnion americanum R R R R R 0 R R R R R R R R Bonnemaisonnia hamifera R R Callophyllis cristata R R R R R 0 0 0 R R Ceramium rubrum C C C C 0 C C C C 0 0 R C 0 0 0 0 0 Chondrus crispus A A C A A C 0 C 0 A A A A R 0 A C A Corallina officianlis O R R R C 0 0 R R R C R C C R R 0 R Cystoclonium purpureum R R 0 0 0 0 0 C 0 0 0 0 0 0 0 R 0 0 M M M M M M M M M M M M M M M M
M M M M M M M M M M M M M M M APPENDIX 3. (continued) September 1979 December 1979
- Manomet Point Rocky Point Effluent Manomet Point Rocky Point Effluent 1 2 3 1 2 3 1 2 3 1 2 3 1 2 3 1 2 3 RHODOPHYTA (continued)
Gracilaria follifera R 0 0 R R R Gymnogongrus crenulatus R R R R Membranoptera alata R R R R 0 R 0 0 R R R Palmaria palmata Phycodrys rubens R 0 0 R 0 0 C 0 0 0 0 0 C R R 0 0 0 Phyllophora pseadoceranoides C 0 0 0 0 0 0 0 C C C 0 C R 0 0 0 C P. trailli P. truncata C 0 0 C 0 0 0 0 C 0 0 0 0 R 0 0 0 C Y Plumaria elegans Polyides rotundus R R R C C R R C A R R R Polysiphonia elongata R R 0 0 0 R R C 0 P. fibrillosa R 0 0 0 0 0 0 R R R 0 R 0 0 P. harveyi C C C 0 C C C R C R R 0 0 R C R C P. nigrescens R R R R P. urceola ta R R R R R 0 0 0 R R 0 R R 0 0 R Rhodomela confervoides R R Spermothamnion repens C C A C C A A C A C A C C C C C A C Total Species Number 18 24 20 19 20 22 25 24 25 17 18 20 21 19 22 22 19 22 KEY: A = abundant, C = c ammon, O = occasional, R = rare.
k N a a I f
i ! Final Report
- Investigations of Entrainment of Ichthyoplankton at Pilgrim
^ I January - December 1979 , l 1 l l i l Marine Research, Inc. I l Fair.outh, Massachusetts l l February 21, 1980 , 1 Revised 1 March 31, 1980 l l l i l l l l f i 1 l
f TABLE OF CO!EEICS s Page i
SUMMARY
i i
- I. INTRODUCTION - 1
- II. MET 10DS 2 III. RESULTS 1
A. Ichthyoplankton 8 a l B. Lobster Larvae 16 IV. LITERATURE CITED 47 APPENDIX
- Al d
i i i
- Appendix available upon request a
!Ii 4 i I O D I _ _ _ _ . . , . - - , . _ . . - - _ . m- . - - - - - -
~
FIGURES I Page
- 1. Entrainment sampling station in PNPS discharge canal. 3
- 2. Mean monthly densities (per 100 m of water) of the numerically dominant fish larvae entrained at the Pilgrim Nuclear Power Station, January through 3 December, 1975-1979. 34 5 TABLES
- 1. Species of fish eggs (E) and larvae (L) obtained in ichthyoplankton collections from the Pilgrim Nuclear Power Station discharge canal, January-December,1979. 17
- 2. Species of fish eggs (E) and larvae (L) collected in the PNPS discharge canal from 1974-1979 19
- 3. Mean monthly densities of the numerically dominant fish eggs and larvae entrained at the Pilgrim Nuclear Power Station, January-December, 1975-1979. 22 4, Su= ary of nu=bers of smelt larvae entrained at PNPS during the months of Apgil and May, 1974-1979. All densities are per 100 e of water. 46
- 5. Mean, maximum, and minimum discharge (cfs) in the Jones River recorded at Kingston, Mass. by the U.S.
Geological Survey for the months of April and May, 1974-1979. 46 APPENDIX I' Fish egg and larval densities, per 100 m of water, for each sa=ple collected in the Pilgrim Nuclear Power Station discharge canal, January-Dece=ber 19 9. Al i I l 1 I
SUMMARY
e Ichthyoplankton samples were collected from the Pilgrim Nuclear Power Station discharge canal in triplicate, biweekly in January, February, and October-December, and weekly March through September. e Eggs and/or larvae of 37 species of fish were obtained during the year.
- Atlantic cod (Gadus morhua) were most abundant among the eggs collected in January, February, March, November, and December. Through most of April American plaice eggs (Hippoglossoides platessoides) were dominant. From
- - the last week of April through mid-August the labrids (tautog, Tautoga I onitis, and cunner, Tautogolabrus adspersus) were most abundant among the eggs. Windowpane (Scophthalmus aquesus), rockling (Enchelyopus cimbrius),
and hake (Urophycis spp.) docinated from late August through September and October, e Larval collections were dominated by sand lance (Arzaodytes sp.) during the months of January, February, March, and April. During these months rock gunnel (Pholis gunnellus) and grubby (Myoxocephalus aenaeus) vere also numerous. Winter flounder (Pseudopleuronectes americanus) were coccon during April ard dominated the larval collections in May. Cunner was the most common larval species during June, July, and August. In September rockling dominated the larval catch along with windowpane, menhaden (Brevoortia tyrannus), and tautog. October collections were dcasinated by rockling, silver hake (Merluccius bilinearis), hake, and windowpane. Atlantic herring (Clupea harengus harengus) were most cocznon among the larvae in November, and sand lance were most cocmon in December. I i
l e Mean monthly densities of the numerically deciinant species of ichthyoplankton I i were compared for the 1975-1979 period (Table 3, Fi5 ure 2). l e One larval lobster (Homarus americanus) was collected in the 1979 ichthyo- gl 1 plankton samples; a stage I larva, July 14 I: ! I I I l I I I I l l = 4 I I 11 I
I . I. INIRODUCTION This report su arizes the results of ichthyoplankton sacpling conducted at the Pilgrim Nuclear Power Station (PNPS) from January through December 1979 by Marine Research, Inc., for Boston Edison Company under Purchase Order No. 64098. I In this report methods are detailed in Section II, results in Section III. Fish egg and larval population densities (per 100 m of water) are tabulated for each sa=ple in the Appendix. I I lI I I I I I I - I I 1
I II. METHODS The entrainment sampling plan for 1979 at the Pilgrim Nuclear Power Station I specified triplicate samples to be collected twice monthly in January, February, October, November, and December, and weekly frm March through September. All samples were collected from rigging mounted approximately 30 meters frm the headwall of the discharge canal (Figure 1) at low tide during daylight. A 0.333-mesh, 60-cm diameter plankton net af fixed to this rigging was streamed in the canal for 6 to 12 minutes depending on the abundance of plankton and detritus. 3 In each case, a minimum of 100 m of water was sampled. Exact filtration volumes were calculated with the aid of a digital flowmeter (General Oceanics Model 2030) mounted in the mouth of the net. All samples were preserved in 107. formalin and returned to the laboratory for microscopic analysis. All fish eggs and larvae were identified to the lowest distinguishable taxonomic category and counted. In most cases, species were identifiable. In certain cases, however, eggs--particularly in the early stages-of development--could not be identified at the species level in the preserved samples. In such cases, species were grouped. A brief description of each of these egg groupings is given below. Cadid::c-Clyptocephalus group (Atlantic cod, Gadus morhur.; haddock, Melano-I l grarr..us aeglefinus; pollock, Pollachius virens; and witch flounder, Glyptocephalus cynoglossus);. egg diameters overlap, no oil globule present. Stage III eggs (t tose containing embryos whose tails have grown free of the yolk; Ahlstrm and Counts,1977) are separated based on relative size and pigmentation cmbinations. Haddock eggs are difficult to identify until shortly before hatching (late stage III). Because of this, some early stage III haddock eggs =ay have been , identified as cod eggs. This error should be quite small judging frm the relatively low numbers of late stage III haddock eggs and haddock larvae i 2
1 I I l I CAPE COO BAY l -
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UNIT 1 INTAKE * . I S ICHTHYOPLANKTON PNPS UNIT 1
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STATION , , 100 METE 9S 'I Figure 1: Entrainment sampling station in PNPS dischar6e card., I 3 .
collected during recent years. The gadidae-Clyptocephalus grouping was not l necessary in January and February because it is unlikely that witch flounder spawn during these months, and haddock spawning is not likely to occur in January. We assumed haddock eggs were absent in February. All eggs of the gadidae-Clyptocephalus type were therefore classified as either cod or pollock based on diff ering egg diameters. Brosme-Scomber group (cusk, Brosme brosme, and Atlantic mackerel, Seceber I scembrus): egg and oil globule diameters overlap. Diff erences in pis=entation permit separation of stage II (early embryo) and stage III eggs. Enchelyopus-Urophycis-Peprilus group (fourbeard rockling, Enchelyopus cimbrius; hake, Urophycis spp.; and butterfish, Peprilus triacanthus): egg and oil globule diameters overlap. Stage III eggs are separated based on dif ferences in embryonic pipentation. Merluccius-Stenotomus-Cynoscion group (silver hake, Merluccius bilinearis; scup, Stenotecus chrysops; and weakfish, Cynoscion regalis): egg and oil glob-ule diameters overlap. Stage III eggs are separated into silver hake and scup-weakfish based on differences in embryonic pipentation. Scup and weakfish eggs, which have rarely been taken, remain grouped throughout their development because differences in embryonic pipentation are subtle and not clearly understood. Labridae-Limanda group (tautog, Tautoga onitis; cunner, Tautogolabrus adspersus; and yellowtail flounder, Limanda ferruginea): no oil globule present, egg diameters overlap. Stage III eggs are separated into labridae and yellowtail flounder based on differences in embryonic pipentation. A high percentage of the two species of labrid eggs are distinguishable, but only with individual, time-consuming measurement (Marine Research,1977a). 4
i - Labrid eggs are therefore grouped in all three stages of developcent in the 1 1979 samples. Paralichthys-Scophthalmus group (fourspot flounder, Paralichthys oblongus, and windowpane, Scophthalmus' aquesus): oil globule and egg diameters as well as pigmentation are quite similar. Separation of these two species, even at I stage III, remains uncertain. They are therefore grouped in all cases. I Eggs of the bay anchovy,(Aachoa critchilli) and striped anchovy (Anchoa hepsetus) are easily distinguishable, but their larvae are not. Eggs of these fishes were therefore listed by species while the larvae are listed si= ply as Anchoa spp. I Several other groups of eggs and larvae were not identified to the species level because adequate descriptions of each species are not available at this time. These groupings are as follows: I
- Urophycis spp. - consists of the red hake (U. chuss), the spotted hake (U. recius), and the white hake (U_. tenuis). Most larvae (and eggs) in this genus collected at PNPS are probably the red hake (see su:=:ary in Hardy 1978).
I
- Menidia app. - consists of the tidewater silverside (M. heryllina) and Atlantic silverside (M. =enidia). Atlantic silverside larvae are probably more likely to occur as far north as Ply =outh based on their = ore northern dis tribution.
- A:modytes sp. - No species designation was given the sand lance because considerable taxoncaic confusion exists in the literature (see for exa=ple Richards et al. 1963; Scott 1968, 1972; Winters 1970). Recently Meyer et al.
(1979) exactined adults collected on Stellwagen Bank and classified them as I A. at:ericanus (= A. hexapterus) . This population is probably the source of larvae entrained at P!GS.
I Prionotus spp. - consists of the northern searobin (P_. carolinus) and the striped searobin (P. evolans).
. Liparis spp. - may consist of the acasnail (L. atlanticus), the gulf snailfish (L_. coheni), the inquiline seasnail (L. inquilinus), and the striped '
seasnail (L. 11 paris). Most of those collected at PNPS are probably L_. atlanticus based on an identification by K.W. Able (personal cocaunication, July 1978). Because of particular interest in rainbow smelt (Osmerus cordax), cunner, I and winter flounder (Pseudopleuronectes a=ericanus), larvae of these species vere classified into three or four arbitrary developmental stages. These l l stages and corresponding length ranges are given belev. l Rainbow s=elt Stage I - From hatching until the yolk sac is fully absorbed. 5-7 cxu TL. Stage II - From the end of stage I until dorsal fin rays become visible. 6-12 :xn TL. Stage III - Free the end of stage II onward. 11.5-20 ::xs TL. 1 Cunner Definitions of developmental stages are the same as for scelt larvae. III Observed size ranges for each stage are: stage I,1.6-2.6 cm TL; stage II, 1.8-6.0 =m TL; stage III, 6.5-14 cm TL. Winter flounder 1 1 Stage I - From hatching until the yolk sac is fully absorbed. 2.3-2.8 cxn TL. i Stage II - Frces the end of stage I until a loop or coil forms in the gut. 2.6-4 cxs TL. I I
I . Stage III - From the end of stage II until the lef t eye migrates past the midline of the head during transformation. 3.5-8 m TL. 7.3-8.2 m TL. I Stage IV - From the end of stage III onward. , 1 l l In most cases, entire sa.ples were examined for fish larvae and the less
- 1 .I coc=on types of fish eggs. When a particular species was especially abundant, aliquot subsa=ples were taken. Such subsa=ples contained 100 or more specimens l of a given species or grouping. Unpublished studies by Marine Research have indicated that subsampling effort can be maintained at a lov level if the number of specimens in an aliquot increases as the fraction represented by the aliquot J'
grows s= aller, c.g.,100 larvae are sufficient in a one-half split, but 200 should be present in a one-quarter split. I I I I I I I I , l I l I I , .
l III. RESULTS l A. Ichthyoplankton
- I' Population densities, per 100 m of water, listed by date, station, and replicate for all sa=ples collected in 1979 are presented in the Appendix. I The occurrence of eggs and larvae of each species by month is su=marized in Table 1.
The ichthyoplankton collected may be s a rized as follows: January: Five species of fishes were represented in the January collections. Both egg and larval densities were quite low. Cod eggs represented 73*'. of the egg total with a mean density for the month of 2.1 per 100 m . A s=all nu=ber of pollock and sand lance eggs cocpleted the egg catch. Among the larvae, sand lance and rock gunnel (Pholis gunnellus) composed 89". of the catch with monthly mean densities of 4.8 and 1.0 larvae per 100 m , respectively. A few cod and grubby larvae (Myoxocephalus aenaeus) completed the catch. February: The nu=ber of species taken remained at five. Cod continued to I dominate ar:ong the eggs with a mean density of 1.6 per 100 m accounting for 957. of the egg catch. Larval collections were dominated by sand lance and rubby with cean densities over the month of 11.1 and 6.6 per 100 m 3 of water, respectively; these two species accounting for 857. of all larvac collected. March: The species count rose to 13 during the month. Four species were represented by egga. Cod accounted for the majority of the egg catch assuming they dominated the gadid-Clyptocephalus grouping at that time. (This appears to be a reasonable assu=ption since no stage III pollock or l I e I
l l witch flounder eggs were taken in March.) Combined with the early stage eggs I classified as gadid-Clyptocephalus, cod represented 807. of all eggs taken during the month with a monthly mean density of 9.7 per 100 m3 of water. Small numbers of American plaice (Hippoglossoides platessoides), winter flounder, and yellowtail flounder composed the remainder of the egg collections. I Eleven species of fish were represented by larvae in March. Sand lancu accounted for 707. of the month's catch with weekly mean densities, per 100 m 3 j I of water, ranging from 9.4 (March 1) to .206.5 (March 15). Grubby and rock Eunnel larvae cccposed an additional 287. of the conth's larval catch. Their I weakly mean densities ranged frca 1.8 to 32.7 per 100 m 3 and 1.2 to 32.3 per 100 m , respectively. April: Seventeen species were taken during the month, eight of these repre-sented by eggs. American plalce dominated the egg collections accounting for 527. of the April egg catch with weekly mean densities ranging between 0.5 and 3 37.3 per 100 m of water. Labrid-Limanda eggs first appeared in April and I increased to a density of 22.4 eggs per 100 m by April 25. Over the month as a whole they represented 267. of the egg catch. Winter flounder eggs were also taken and in f act cceposed the largest single collection during the month 3 (SM eggs per 100 m , April 25). Winter flounder eggs were not considered in the percentage figures presented above because they are demersal and adhesive. Their appearance in the discharge samples does not therefore quantitatively reflect their abundance in the surrounding water. Those collected were prob-ably scoured frca the bottom by currents or other fish or may be the result of a spawning near the plant intake where they were entrained before adhering to the botten. I Larvae representing 13 species were found in the April collections. Sand lance continued to dominate the catch as in January, Fe.bruary, and March with I e . I
3 a mean density over the month of 92.1 larvae per 100 m of water accounting l for 767. of the month's catch. Grubby, rock gunnel, and winter flounder ac-counted for an additional 197. of the catch. Maximum weekly mean densities 3 for these species were 25.6, 8.4, and 8.4 per 100 m for the grubby, rock gunnel, and flounder, respectively. May: Of the 22 species of fish represented in the May ichthyoplankton collec-tions 12 were represented by eggs. Labrid-Limanda eggs accounted for 917. of the egg total although they did not become abundant until the last week of the month. At that time the labrids probably dccinated the grouping. Over the month, weekly mean densities for the grouping ranged frca 7.8 per 100 m on 3 May 4 to 7066.5 per 100 m on May 24 Mackerel eggs were second in order of abundance assuming they decinated the Broscc-Seceber egg grouping; the ec= para-l tively low numbers of stage II and III cusk eggs and cusk larvae supports this assumption. The Drosme-Scomber grouping cccbined with mackerel eggs accounted for an additional 57. of the egg catch with a cean density calculated over the
=onth of 82.2 eggs per 100 m3, Twenty species of fish larvae were taken in the May samples. Winter flounder, sand lance, and seasnail (Liparis spp.) dominated the catch accounting for 647.
of the total. Weekly larval vinter flounder densities ranged from 13.0 to 41.o per 100 m3 . Sand lance, the most abundant species from January-April, declined 3 in May f rom a mean of 45.2 per 100 m on May 4 to 0.4 per 100 m 3on May 24 Scaenail also declined over the month fecc a high density of 32.6 per 100 m3 3 on May 9 to a low of 10.4 per 100 m on May 24. Radiated shanny (Ulvaria subbifurcata), grubby, and mackerel accounted for an additional 237 of the larval catch. June: The species count reached 24 in June, the highest during this year. I
)
Labrid eggs clearly dominated among the 16 species of eggs collected, assuming 1 10 5
they dominated the labrid-Limanda group.* Combined with the grouped eggs they composed 977, of the June egg total with weekly mean densities ranging between 3 1332.6 and 10449.6 per 100 m of water. The Paralichthys-Scophthal=us and I Enchelyopus-Urophycis-Peprilus egg groupings accounted for the majority of the re=aining eggs. Within these tro Sroups fourspot flounder and butterfish were probably ce=paratively unce= mon, judging by the larval collections. . I Nineteen species of fishes were represented by larvae. Cunner accounted l i for 47". of the larval densities with weekly mean densities ranging between 12.9 and 65.0 per 100 3m of water. Mackerel, vinter flounder, rockling, and tautos contributed an additional 387. of the larval catch. Respective maximum weekly cean densities for these species were 24.4, 27.1, 12.2, and 7.3 per 100 m3 . Both mackerel and flounder declined during the second half of the conth. I July: Twelve of the 21 species found in July were represented by eggs. Labrid eggs clearly dominated a=ong these, as they did in June, accounting for 967. of the total (if yellowtail flounder eggs are considered to have been absent fro = the labrid-Limanda grouping). Mean densities for both labrid and labrid-Limanda eggs combined ranged from 232.3 to 4937.7 per 100 3m . Rockling, hake, and windowpane accounted for =ost of the re=sining eggs in the sa=ples. I July collections contained relatively few larvae. Cunner and rockling were most abundant among the 18 species taken. They cocposed 767. of the month's larval catch with weekly =ean densities ranging between 0 and 24.4 3 per 100 m for the cunner and 0.5 and 7.3 per 100 m for the rockling. I *During the months of June, July, and August, yellowtail flounder stage III l I eggs and larvae averaged 2.9, 1.8, and 0 per 100 =3 of water, respectively. These figures are quite low relative to the densities of stage III labrid eggs, and cunner and tautog larvae. Therefore the vast majority of labrid-Limanda eggs are assu=ed to be labrid eggs during these months. I 11
Aus;ust: Eleven species were represented by eggs. The labrids continued to I dominate among them although they declined steadily each week. Over the month as a whole they accounted for 40.57, of the catch while declining from a weekly mean density of 561.6 per 100 m3 on August 2 to 1.5 per 100 m 3on August 30. As in June and July, rockling, hake, and windowpane accounted for most of the remaining eggs; 56.27. ccebining all three. The number of species represented by larvae declined to 15. Cunner, hake, and rockling accounted for 32,19, and 127. of the month's larval catch, respec-3 tively. Weekly =ean densities, per 100 m of water, for these species ranged frcc 0.6 to 9.1 for the cunner, O to 8.0 for the hake, and 0.5 to 2.7 for the rockling. September: Nine species were represented by eggs in this =enth's collections. I Windowpane , hake, and rockling cccbined accounted for 817. of the =enth's catch assuming no fourspot flounder or butterfish eggs were taken among the Enchelyopus-Urophycis-Peprilus and Paralichthys-Secphtha1=us egg groups. Weekly mean den-sities, per 100 m of vnter, ranged from 3.1 to 22.9 for the Paralichthys-Scophthal=us group, 0.9 to 30.1 for the Enchelyopus-Urophycis-Peprilus group, 1.4 to 21.0 for stage III hake eggs, and 1.3 to 10.1 for stage III rockling eggs. Silver hake accounted for an additional 177. of the month's eggs, assuming they accounted for =ost of the eggs grouped as Merluccius-Stenotomus-Cynoscien. The vast =ajority of silver hake eggs (977.) were found on September 21. Larval collections contained seven species, each of which were represented by a small nt=nber of speci= ens. Rockling accounted for 49% of the month's larval catch with weekly mean densities ranging between 0.5 and 1.9 per 100 m3 of water. Windowpane, menhaden, and tautog contributed much of the rc=aining catch. I 12
I October: Tha numbar of spacies represented by eggs continued to decline to five. Windowpane, rockling, and hake - the principal species in September - continued to dominate in October. Monthly mean densities, per 100 m of water, were 2.6 for the Paralichthys-Scophthal=us group, 2.5 for stage III rockling, 1.2 for the Enchelyopus-Urophycis-Peprilus group, and 0.1 for stage III hake eggs. I Six species.of larvae were found in the October collections. Rockling, silver hake, hake, and windowpane accounted for 977. of the catch with monthly 3 cean densities of 3.9,1.0, 0.6, and 0.5 larvae per 100 m , respectively. I November: Only the Atlantic cod was represented in this month's egg collec-tions, assu=ing all those stage I and II eggs listed as gadidae-Clyotocephalus were in fact cod; this assu=ption appears justified since no stage III eggs or larvae of the pollock or witch flounder were found. A =ean density of 10.6 eggs per 100 m was recorded over the month as a whole. Among the larvae three species were identified. The Atlantic herring (Clupea harengus harengus) accounted for 507. of the conth's total with a =ean i 3 density of 0.3 per 100 m . Menhaden accounted for 377. with a mean density of
- 0. and rockling accounted for 137. with a mean density of 0.1.
l December: Only cod eggs were taken in the Decc=ber egg collections with the I 3 exception of one unidentified egg. A mean density of 5.0 per 100 m y,, l recorded on December 10 and 3.8 per 100 m3 was recorded on Decc=ber 21. 1 Three species were found among the larvac. Sand lance accounted for 967. l I l 3 of the total with =ean densities per 100 m of water of 0.2 on December 10 l and 19.4 on Dece=ber 21. A few cod and rockling =ade t.p the remainder of I the larval catch. L F 13 i
Tcble 2 su=arizes by year all species of eggs and larvae collected in I the PNPS discharge canal from 19"/4-1979. Monthly mean densities for the nu-merically dominant species of eggs and larvae taken in 1979 are su=arized in Table 3. Similar data for 1975 through 1978 were also tabulated for com-parison after being standardized as follows:
- 1. Only 0.333-cm mesh net data were used in those cases (1975) when field sampling was carried out using both 0.333 and 0.505 mesh nets.
2 When, as in 1976 and 1977, 24-hour sampling series were conducted, the samples taken nearest the time of daylight low tide were selected I for comparison, since this confor=s to the routine specification for the tLne of entrainment sarapling.
- 3. For the sa=e reason only daylight low tide data were used when, in 1975, samples were also taken at high tide and/or at ni3 ht.
4 Cod and pollock egg densities were surraed to make up the category I
" gadidae" since these eggs, which are listed separately in recent reports, were not distinguished in earlier ones.
- 5. Sculpin larvae were identified to species beginning in 1979 following Khan (1971). They appear as Myoxocephalus spp. in Table 3 for ccm-parison with past years.
Although samples were in fact taken once in April 1976 and once in March 1977, comparisons with other years when sa=pling was weekly are not valid and consequently do not appear in the Table. Data collected in 1974 were not included because samples were not collected at low tide in all cases. Mean larval densities summarized in Table 3 were also plotted in Figure 2. As indicated in Table 3 and Figure 2, ichthyoplankton densities recorded in I 1979 do not appear unusual. In each case, densities fell within the level of variation observed over the previous four years. Several of the observed den-sities are of general interest. Sand lance and winter flounder densities, 14 I
l which were cecparatively high in April and May of 1978, declined in 1979 to l l a level more cccparable with 1975, 1976, and 1977. Sand lance densities were l again eccparatively high in December 1979, Labrid-Limanda eggs were relatively abundant in May of 1978 and 1979 and re=sined abundant in June 1979. July l 1979 labrid-Li=anda densities were comparatively low however. l Since the labrid-Limanda densities seem to vary to scoe extent in the timing of their peaks, monthly mean densities for May through August, taken l from Table 3, vere added within each year. This s - tion indicates that the l l 3 1975-1979 densities may be ranked as follows: 1977 (8835 per 100 m ), 1979 3 (8274 per 100 m ),1978 (6969 per 100 m3 ),1975 (5753 per 100 m3), and 1976 (3329 per 100 m ). Including stage III labrid eggs does not change the rank order. I Larval rainbow s=elt have been of special interest at PNPS because, being fr shwater spawners, their presence in the discharge waters of the plant may indicate that at least acce of the plant's cooling water is coastal in origin. Table 4 su==ari:es the densities of larval s=elt entrained at PNPS in April and May (the montha when they are most coccon) 1974-1979. Smelt were rela-tively abundant only in 1974 and 1977, which suggested (MRI 1978) that their presence in the discharge may result from periods of high freshwater ru..,ff which flushes larvae frce th.e streams in which they were spawned. Table 5 tabulates USGS discharge data for the Jones River in Kingston, Massachusetts, for the months of April and May. The Jones River is a well known smelt spawn-
- ing area (Lawton et al. 1979) which drains into Kingston Bay north of PNPS.
Flow rates were higher in 1974 and 1977 than in 1975 and 1976. However, the data free 1978 anu 1979 appear to be inconsistent, i.e., flow rates were rela-tively high while smelt densities were relatively low. This may indicate that l larval smelt production was relatively low in 1978 and 1979 or may si= ply l 15
I reflect sa=pling error, i.e., with caly three sa=ples taken per week there is a high probability of missirg!; a pulse of larvae flushed from the Jones River. B. Lobster Larvae All ichthyoplankton sa=ples collected frcra May through October were thor-oughly examined for the presence of lobster larvae (Hecarus a=ericanus). One-such larva was obtained in the 1979 sa=ples - a stage I larva in replicate sa=ple 1 on July 14. This coc: pares with past years as follows: 1978: none found. 1977: 3 larvae - 1 stage I on June 10; 2 stage I on June 17. I 1976: 2 larvae - 1 stage I on July 22; 1 stage IV-V on August 5. 1975: 1 larva - 1 stage I, date unknown. 1974: none found. The lobster la:tae collected in 1976 were obtained during a more intensive lobster larvac program which c= ployed a 1 =eter net, collecting reistively large sa=ple vole =es, in addition to the standard 60-c= plankton net (MRI 1977b). Both larvae taken in 1976 were collected in the meter net; none were found in the routine ichthyoplankton sa=ples. I I I 16 I I
7 _n_ n M M n R U _R F 1__JR R R R R R FR Tchlo 1: Species of fish eggs (E) and larvas (L) obtained in ichthyoplankton collections from the Pilgrim Nuclear Power Station discharge canal, January-December,1979. . 4 Species Jan Feb Har Hay Apr Jun Jul Aug Sep Oct Nov Dec Am3rican eel Anguilla rostrata J* J Alawife/blueback Al sa pseudoharengue/acetivalis i rring L Atlsntic menhaden Brevoortia tyrannus L E/L E/L E!L E/L L Attentic herring Clupea hareagus harengus L L L L Bay anchovy Anchoa mitchilli E Anchovy Anchoa app. L ' R=inbow smelt Osmerus mordax L Coccefish j,ophius americanus E E E L L Cusk Broome broeme E E/L g Feurbeard rockling Enchelyopus cimbrius E E/L E/L E/L E/L E/L E/L L L Attentic cod Gadus morhua E/L E/L E E/L E/L E/L E E E E E E/L H:ddock Helanogrammus aeglefinus L Silver hake Herluccius bilinearis E E E/L E/L E/L E/L Pollock Pollachius virens L E E/L L , Unkes Urophycis app. E/L E/L E/L E E/L Hummichog Fundulus heteroclitus E Striped killifish F. majalis J Silvarsides Henidia spp. L L N:rthern pipefieh Syngnathus fuscus J J J J Nsethern kingfish Henticirrhus saxatilis L
*J = Juvenile
Table 1 (continued). Species Jan Feb Har Apr May Jun Jul Aug Sep Oct Nov Dec Wrescos Labridae E E E E E E Tcutog Tautoga onitis L L L L L Cunner Tautogolabrus adspersus L L L L Radiated shanny Ulvaria subbifurcata L L L Hock gunnel Pholis gunde11us L L L L L Wr> mouth Cryptacanthodes maculatus L L Sand iance Manodytes sp. E/L L L L L L L Atlantic mackerel Scomber scanbrus E/L E/L E/L E/L Butterfish Peprilus triacanthus E/L L Ssorchin Prionotus opp. E E E gprubby Hyoxocephalus senaeus L L L L L L A111getorfish Aspidophoroides monopterygius L Seacnnil Liparis app. L L L L L Pcuropot flounder Paralichthys oblongus L L L L Wind owpane Scophthalmus aquosus E/L E/L E/L E/L E/L E/L . Witch flounder clyptocephalus cynoglossus E/L E/L E/L E/L E Am rican plaice !!Lppoglossoides platessoides E E/L E/L E/L E/L Yellowtati flounder Limanda ferruginea E E E/L E/L E/L E/L E Winter flounder Pseudopleuronectes americanus E/L E/L E/L L L
m m M M M M M M M M M M M M Teble 2: Species of fish eggs (E) and larvac (L) collected in the PflPS discharge canal from 1974-1979. Species 1974 1975 1976 1977 1970 1979 American eel Anguilla rostrata J* J J J J Alewife /blueback herring Alosa app. L L L J L Atlantic menhaden Brevoortia tyrannus E/L E/L E/L E/L E/L E/L Atlantic herring Clupea harengua harengue L L L L L L Anchovy Anchoa app. L L L L L Bay anchovy Anchon mitchilli E E E Hainbow amelt comerus mordax E/L L L L L L Ccosefish Lophius americanus E/L E/L E E/L E/L E/L Cusk Droeme broome E E/L E/L E/L E/L Fourbeard rockling Enchelyopus cimbrius E/L E/L E/L E/L E/L E/L Atlantic cod Cadus morhua L E/L E/L E/L E/L E/L IInddock Helanogrannus neglefinus L L E/L E/L E/L L Silver hake Herluccius bilinearts E/L E/L E/L E/L E/L E/L Atlantic tomcod flicrogadus tomcod L L Pollock Pollachius virens L E/L E/L E E/L E/L llake s Urophycis spp. E/L E/L E/L E/L E E/L.
- Cusk-eels /Ecipouta Ophidiidac-Zoarcidae L Atlantic needlefish Strongylura marina L Killifish Fundulus app. E E Hummichog Fundulus heteroclitus E Striped killifish F. majalis J Silversides llenidia spp. L L L L Atlantic silverside Henidia menidia L E/L E/L E
*J = Juvenile
Table 2 (continued). Species 1974 1975 1976 1977 1978 1979 florthern pipefish Syngnathus fuscus J* J J J J J Dlack sea bass Centropristis striata, L Scup St.anotomus chrysops L L llorthern kingfish Henticirrhus saxatilis E L L Wrasses Labridae E E E E E E Tautog Tautoga onitia L L L L L L Cunner Tautogolabrus adsperous L L L L L L Snakeblenny Lumpenus lumpretacformis L L Rcdiated shanny Ulvaria subbifurcata L L L L L L Rock gunnel Pholis gunnellus L L L L L L Wrymouth Cryptacanthodes maculatus L L L Sand lance Ammodytes sp. L L L L L E/L Seaboard goby Gobiosoma ginsburgi L L Atlantic mackerel Scomber acombrus E/L E/L E/L E/L E/L E/L Butterfish Peirilus,triacanthus E/L E/L E/L E E E/L Snarobins Prionotus spp. E/L E/L E E E . Sculpin _Hyoxocephalus spp. L L L L L L Aspidophoroides monopterygius Alligatorfish L Lumpfish Cyclopterus lumpus L L L Saasnail Liparis opp. L L L L L L Smallmouth flounder Etropus microstomus L Sumner flounder Paralichthys dentatus E/L E/L Fcurspot flouncter P. oblongua E/L E/L E/L L
*J = Juvenile M M M M M M M M M M E E E E E
Table 2 (continued). Species 1974 1975 1976 1977 1978 1979 Windowpane Scophthalmus aquosus E/L E/L E/L E/L E/L E/L Witch flounder Glyptocephalus cynoglossus E/L E/L E/L E/L E/L E/L American plaice Ilippoglossoides platessoides E/L E/L E/L E/L E/L E/L Yellowtail flounder Limanda ferruginen E/L E/L E/L E/L E/L E/L Winter flounder Pseudopleuronectos americanus E/L E/L L E/L E/L E/L llogchoker Trinoctes maculatus E E Northern puffer Sphoeroides maculatua L U
Table 3: Hean monthly densities of the numerically decinant fish Format: eggs and larvae entrained at the Pilgrim Nuclear Pcwer Range Station. Januarv December, 1975-1979. See t xt for dat:ft._
~ ~ JANUARY 1975 1976 1977 1978 1979 EGGS
- Gadidae-Clyptocephalus - - - -
0.5 0.2 2.2 Gad idae
- O-1 0 - 0.7 0-5 Enchelyopus-Urophycis- , ,
Peprilus Enchelyopus cJr.brius** 0.1 0 0 0 - 0.6 Urophycis spp. 0 0 0 Lab rid ae-Limand a 0 0 0 Labridae 0 e c 0 0 Secrnber scochtus 0 = = 0 0 Paralichthys-Scophthalmus 0 -
- O O 0.6 a 4 0.2 2.7 Total 0-1 0 - 0.7 0-5
- n. **
LARVAE Clupea harengus harengus 0 0.6 Enchelyopus cimbrius 0 0 0 Tautogolabrus adspersus 0 0 0 Ulvaria subbifurcata 0 0 0 C Pholis gunnellus 07 - 0-3 Am= dytes sp. 6.7 1!4' 478 lI 0 - 18 0-4 0 - 11 E Seceber sceabrus 0 0 0 Hyoxocephalus spp. 1.4 0.3 0.5 i' 0-6 0-1 0-1 Liparts app. 0 0 0 Pseudopicuronectes 0 0 0 ! americanus ' 9.4 7.4 8.1 Total 0 - 15 3 - 13 0 - 12 l
- Represents all three egg stages from January through February.
l
** Represents all three egg stages from January through March.
l ! 22
i Table 3 (continued). Format: Range FEBRUARY 1975 1976 1977 1978 1979 EGCs Gadidae-Glyutocephalus - - - Gadidae
- 0.9 2.4 1.6 0-3 0-5 0-3 Enchelyopus-Urophycis- ~ ~ ~
Peorilus Enchelyopus cimbrius** 0 0 0 Urophycis spp. 0 0 0 Labrid ae-Limanda 0 0 0 Labridae 0 e e 0 0 Scccber scombrus 0 = = 0 0 Paralichthys-scophthalcus 0 y - 0 0 1.0 a a 2.5 1.6 Total 0-3 0-5 0-3
- c. c.
IARVAE Clupea harengus harengus 0.1 x x 0.6 0 0 - 0.5 0-2 Enchelyopus cimbrius 0 < < 0 0 Tautocolabrus adspersus 0 O O 0 0 0 I divaria subbifurcata Pholis gunnellus 3.7 0 - 14 o o 0-3 1.2 2.9 0 - 10 J
)
I Armodytes sp. Seceber scombrus 2.1 0-8 0
= =
0.6 - 24 8.8 0 11.1 4 - 21 0 j j Myoxocephalus spp. 2.2 0.2 6.6 l 0-7 0-1 0 - 26 , Liparis spp. 0 0 0 Pseudopleuronectes 0 0 0 cmcricanus 10.8 11.0 20.9 Total 0 - 17 0.8 - 29 4 - 58
- Represents all three egg stages frce January thrcugh February.
** Represents all three egg stages frec January through March.
23 l l
Table 3 (continued). Format: R nge MARCH 1975 1976 1977 + 1978 1979 EGGS Cadidae-Glyptocephalus 1.5 9.2 0-2 0.8 050. 3 050. 32 Gadidae
- 0-3 0-1 0-3 Enchelyopus-Urophycis- , , ,
Peprilus Enchelyopus cimbrius** 0 0 0 Urophycis spp. 0 0 0 Labr id ae-Li=anda 0 0 0 Labridae 0 0 0 o Seceber scombrus 0 0 0 Paralichthys-Scophthalmus O 0 0 g E l g Total
'* 4 2.8 12.1 0.8 - 41 0-5 0.4 - 35 LARVAE Clupea harengus harengus % 0 0 2 0 1 Enchelyopus cimbrius 0 < 0 0 Tautogolabrus adspersus O m 0 0 Ulvaria subbifurcata 0 0 0 Pholis gunnellus 26 - 47 0. 28 1 34 g 29.5 2 11.1 54.0 y g,, ,p, 11 - 60 0.7 - 22 9 - 228 Scomber scombrus 0 0 0 l 61.4 Myoxocephalus spp. 17 , g 7 32.8 12.3 0.5 11 - 65 1 g5 Liparis app. 0 0 - 3. 0-4 Pseudopleuronectes 0.03 0 0 americanus 0 - 0.5 l '^
127.5 55.7 76.8 66 7 6 26 - 96 11 - 293
- Represents all three eEg stages from January through February.
** Represent: all three egg stages from January through March. +A single set of as=ples was taken in 1977. These data were not included in this E cecparison because veckly data sets ve g available in 1975, 1978, and 1979 3
Mean Table 3 (continued). Format: Range APRIL
~'1975 1979 1976+ 1977 1978 EGGS 1.7 0.7 8.1 3.5 Gadidae-Glyptocephalus 0-5 0-2 2 - 14 0.8 - 12 Gadidae
- O-6 0-3 0.6 - 14 0-3 Enchelyopus-Urophycis- 0 .S.
- O Peprilus 0-1 0-1 Enchelyopus cimbrius** 0 0 10 0 2 0 2 Urophycis spp. 0 0 0 0 0.8 0*0 2*S 11*1 8.1 Labr id ae-Lir.and a ,
0 - 18 0-7 0 - to 0 - 28
.._ Labridae 0.2 0.5 0.08 0 ,
0 - 0.9 0-3 0-1 Secnber scombrus 0 0 0 0 Paralichthys-Scophthalmus 0 0 0 0 - 0.7 33.4 10.2 63.1 73.9
'*1 1 - 84 1 - lb 8 - 114 4 - 546 LA.RVAE Clupea harengus harengus 0 0 12 0 1 0 2 3 Enchclyopus ci:::brius 0 0 0 0 I Tautogolabrus adspersus Ulvaria subbifurcata 0
5.4 0 - 19 0 3.9 0 - 19 0 0.2 0-2 0-1 0 0.3 1.8 4.0 1.5 3.7 Pholis gunnellus 0-8 0 - 19 0-5 0 - 13 6.5 36.8 388.8 92.1 Arnod y tes sp. 6 - 1252 26 - 196 I Seceber scecibrus 0.8 - 18 0 6 - 85 0 0 0 7.2 30.7 21.3 16.3 Myoxocephalus spp. 3 T 12 14 - 57 0 - 57 1 - 32 3.5 16.9 1.8 2.1 Liparis spp. 0-8 0 - 11 0 - 72 0-7 j Pseudopleuronectes 3.1 9.5 35.6 2.9 I americanus 0.8 10 0 - 21 0 77 0-8 1 29.7 103.1 458.2 120.5 Total 55 - 154 21 - 1324 57 - 238 14 - 43
- Represents all three egg stages frce January through February.
** Represents all three egg stages frec January through March. +A single set of sampics was taken in 1976. These data were not included in this cecparison because veckly data sets werg available in 1975 and 1977-1979. ;
l
Mean Table 3 (continued). Format: Range MAY 1975 1976 1977 1978 1979
~
EGGS l 1.0 2.3 3.4 3.4 1.4 Gadidae-Glyptocephalus 0-3 0-6 0 - 11 0 - 14 0-5 l'.1 1.5 1.2 9.6 1.8 Gadidae
- O-3 0-4 0-3 0 - 61 0-5 Enchelvopus-Urophycis-
^
8.3 13.3 12.5 27.8 9.5 Peprilus 0 - 30 0 - 72 5 - 22 2 - 125 0.6 - 34 Enchclyopus cimbrius*'* 0 - 91 0 - 32 0 - 37 0 - 15 6 - 70 Urophycis spp. 0 0 0 0 0 3 145.8 12.0 280 .8 1843.4 1491.9 Labridae-Limanda 2 - 1248 5 - 23 3 - 1240 3 - 11609 6 - 9475 0.3 8.6 20.5 4.1 Labridae 0-2 0 - 55 0 - 169 0 - 19 1.8 1.2 12.7 8.5 37.5 Seceber sco=brus 0-6 0-5 0 - 67 0 - 62 0 - 155 10.1 6.3 12.5 30.4 21.0 Paralichthys-Scophthalmus 0 - 64 0 - 19 2 - 32 0 - 169 0 - 76 Total 196.5 74.7 396.3 2017.8 1638.3 12 - 1366 35 - 126 31 - 1324 13 - 12428 45 - 9925 LAF.VAE Clupea harengus harengus 0 0 0 24 0 1 0 5 Enchelyopus cimbrius 0 10 0 13 0 1 0 19 0 19 Tautogolabrus adspersus 0 0 0 0 0.2 0-2 Ulvaria subbifurcata 65.4 7.3 5.7 43.5 5.2 10 - 235 1 - 24 0 - 20 11 - 141 0 - 23 Pholis gunnellus 0.1 0 0 0.4 0.08 0 - 0.5 0-4 0-1 A= dytes sp. 4.0 2.5 2.2 79.9 20.1 0 - 22 0-8 0-7 0 - 526 0 - 88
- Sccaber scombrus 0.1 0 0 2.6 6.1 0 - 0.4 3.2 0.5 1.2 0 - 27 0.3 0 - 29 5.9 3
Myoxocephalus spp. 3 0 - 11 0-2 0-9 0 - 37 0 - 17 Liparis app. 9.2 13.0 38.9 37.0 20.3 0 - 30 6 - 31 0 - 112 1 - 92 6 - 40 Pseudopleuronectes 13.9 7.4 16.3 38.0 18.4 americanus 2 - 36 2 - 18 4 - 29 0 - 129 13 - 40 l Total 99.6 37.9 81.9 222.2 104.1 l 28 - 283 15 - 76 24 - 185 33 - 660 66 - 210 l
- Represents all three egg stages frca January through February.
** Represents all threc egg stages frec January through March.
26
Macn Table 3 (continued). Format: Range JUNE 1975 1976 1977 1978 1979 I EGGS Cadidae-Glyptocephalus 0 4 0 6 0 11 0 7 0 5 0.8 1.5 5.3 2.0 0.4 Gadidae
- O-3 0-4 0 - 27 0-7 0-2 l Enchelyopus-Urophycis- 28.5 11.3 24.4 75.8 38.0 l Peprilus 16 - 55 2 - 25 0 - 96 0 - 308 17 - 98 l 20.0 25.6 51.! 14.7 24.3 I Enchelyopus cimbrius**
Ur phycis spp. 1 - 76 1.5 0-6 9 - 90 0.7 0-2 5 - 114 4.7 0 - 15 0 - 33 4.3 0 - 14 2 - 65 10.2 0 - 27 I Labr idae-Limanda 2432.0 699.0 5739.1 1317.7 809 - 5501 147 - 2258 289 - 19078 24 - 3876 1060 - 10505 5217.8 l Labridae 0 594 7 49 26 5. 81 'd i2~ 50 4 126.3 5.0 55.0 151.8 18.0 Secnber scombrus 4 - 746 0.8 - 19 6 - 199 0 - 360 4 - 41 Paralichthys-Scophtha1=us 2 8 0 3 3 - 129 0 13 2 20 - 41 2819.8 856.2 6301.5 1934.7 5620.2 Total 819 - 5718 342 - 2393 609 - 19425 226 - 5917 1401 - 11522 LARVAE I Clupea harengus harengus Enchelyopus cimbrius 0 50.1 0 28.7 0 128.2 0 40.2 0 7.4 0 - 137 0 - 46 84 - 248 0 - 145 1 - 15 11.3 2.6 11.5 19.5 38.8 Tautogolabrus adspersus 0 - 107 0 - 39 0 - 13 0 - 750 4 - t8 i Ulvarta subbifurcata 0 2 0 28 0 12 0 3 Pholis gunnellus 0 0 0 0 0 2 Ammodytes sp. 0 0 0 0 2 0 2 1 Seceber secnbrus 39.9 4.2 14.0 31.5 9.9 O - 149 0 - 15 OT TS 0 - 126 0 - 37 I Myoxocephalus spp. 0 0 0.7 0 0 0 l l 2.1 6.2 16.0 1.3 Liparis app. 0 - 7' O.- 50 0 - 28 2 - 65 0-4 Pseudopleuronectes 5.5 6.6 4.6 15.9 9.7 americanus 0.5 - 15 0 - 47 0 - 16 0 - 54 0 - 39 117.9 55.1 297.2 176.7 82.5 Total 14 - 260 8 - 139 325 - 641 51 - 343 2 U 154
- Represents all three egg stages from January through February. l l
** Represents all three egg stages from January through March. l 27
Mean l Table 3 (continued). Format: Range JULY 1975 1976 1977 1978 1979 EGGS Gadidse-Clyptocephalus 0 2 0 9 0 2 0 4 Gadidae
- 0 0 0 13 0 2 0- .8 Enchelyopus-Urophycis- 26.6 271.8 656.3 389.2 17.5 Peprilus 2 - 132 3 -- 943 10 - 2858 50 - 1445 4 - 49 Enchclyopus cimbrius**
O 10 0 10 0 14 0 9 0 18 0.7 27.9 34.7 74.9 10.2 Urophycis spp. 0-2 0.7 - 70 0 - 113 5 - 184 0 - 38 2972.0 2588.1 2793.4 3275.8 1430.4 Labrid ae-Limanda 182 - 9861 75 - 6817 814 - 8537 482 - 8086 154 - 6904 Labridae 44.3 232.6 223.6 210.8 54.1 0 - 170 39 - 460 11 - 791 93 - 386 12 - 126 Seceber scombrus 0 1 0 20 0 35 0- 9 0 9 Paralichthys-Scophthalmus 0 23 0 9 2 - 118 20 71 2 - 27 3056.9 3235.4 3936.2 4117.3 4624.2 192 - 10041 303 - 4115 962 - 12306 677 - 8711 207 - 7112 IARVAE Clupea harengus harengus 0 0 0 0 0 Enchelyopus cimbriu 6.4 5.8 34.3 1.1 3.2 O - 27 0 - 25 25 - 42 0-3 0-8 5.2 30.8 20.1 11.2 8.9 Tautogolabrus adspersus 0 - 15 0 - 124 0 - 155 0 - 110 0 - 39 Ulvaria subbifurcata 0 0 0 0 0 Pholis gunnellus 0 0 0 0 0 Ar=od y t e s sp. 0 0 'O O O Scccber secebrus 0 O 12 0 13 0 52 0 2 Hyoxocephalus spp. 0 0 0 0 0 .8 0.3 0.1 0.04 Liparis app. 0 0-2 0 0-1 0 - 0.5 Pseudopleuronectes 0.1 0.1 0.2 0.1 0 americanus 0 - 0.8 0 - 0.8 0-2 0 - 0.6 i 19.1 50.6 69.5 30.9 47.6 Total 0 - 42 10 - 153 4 - 275 4 - 211 0 - 57
- Represents all three egg stages fr'cc January through February.
** Represents all three egg stages frcm January through March.
28
Table 3 (continued). Format: R e AUGUST 1975 P?6 1977 1978 1979 EGGS Gadid ae-Glyptocephalus 0.1 0.4 0.7 0.9 0.2 0 - 0.9 0-2 0-1 0-2 0-1 0.2 0.3 0.06 0.09 Gadidae
- O 0-1 0-1 0 - 0. 7 0 - 0.8 Enchelyopus-Urophycis- 4.8 104.9 17.4 206.4 132.6 Peprilus 1 - 14 20-318 13 - 21 5 - 490 2 - 502 2.0 10.9 2.3 12.8 10.5 Enchclyopus cimbriuse 0-4 2 - 26 2-3 0 - 56 0.5 - 36 2.2 39.9 15.4 80.1 18.3 Urophycis spp.
O-8 3 - 76 9 - 25 0 - 250 0.8 39 I Labridae-Limanda 202.7 0.5 - 896 2.6 30.2 1 - 90 9.7 22.0 17 - 31 20.3 531.9 0 7 34 19.6 0.6 133. 6
- 16.2 $33 l
Labridae 0 - 72 I Secrnber scombrus 0-6 0 0 - 20 0 14 - 31 0 0 - 88 1.0 0-7 0.2 0 - 0.5 j 22.9 37.0 6.5 37.6 46.4 I Paralichthys-Scophtha1=us 8 - 48 230.96 13 - 69 249.5
'J - 10 11-. 9 1 - 96 899.6 10 - 86 369.8 Total 21 - 920 57 - 584 101 - 128 30 - 2445 22 - 1199 LARVAE Clupea harengus harengus 0 0 0 0 0 1.0 12.6 1.6 1.9 1.7 Enchclyopus ci:::brius O-3 0 - 25 1-2 0 - 13 0.5 - 4 I Tautocolabrus adspersus 0 15 2 2 0 1 0 3 0 10 Ulvaria subbifurcata 0 0 0 0 0 Pholis gunnellus 0~ 0 0 0 0 Ammodytes sp. 0 0 0 0 0 0.07 Secruber scocbrus 0 0 0 0 0-1 Myoxocephalus spp. 0 0 0 0 0 Liparis spp. 0 0 0 0 i 0 1 Pseudopicuronectes 0 *' O O O americanus 0-2 I
1 1 20.5 52.8 3 .'9 f.0 14.8 To tal. 1 - 17 8 - 126 2-8 0 - 29 5 - 28
- Represents all three egg stages from January through February.
** Represents all threc egg stages frce January through March.
29
Table 3 (continued). Format: Range SEPTEMBER 1975+ 1976 1977 1978 1979 EGGS 0 0.1 0.06 Gadidae-Clyptocephalus 0 0-1 0 - 0.7 Gadidae
- O O O O Enchelyopus-Urophycis- 10.7 10.1 18.7 13.9 Peprilus 4 - 20 1 - 23 2 - 32 0.5 - 36 Enchclyopus cimbrius** 30.7 19 _ 39 0 29 0 24 '0 12 Urophycis spp. 5.7 10.0 13.0 7.4 1-8 0 - 42 0 - 32 0 - 23 Labridae-Li:unda 0 6 0 3 0 6 0 2 Labridae 0
O 4 0 0.9 O 3 Seceber sec=brus 0 0 0 0 Paralichthys-Scochtha1=us 3- 0 1 03 ~ 4- 1 2 - 26 1 Total 75.6, 94.4 s 65.3 50.1 29 - 126 10 - 334 9 - 154 11 - 110 a LGVAE g Clupea harengus harengus 0 0 2: 0 0 1 Enchelyopua cimbrius g 4 0 3 0 5 7 0.9 0.2 " 0.5 Tautogolabrus adspersus 0 0-2 0 - 0.9 0-2 Ulvaria subbifurcata 0 0 0 0 Pholis gunnellus 0 0 0 0 0 l
- c Am=cdytes sp. 0 0 0 0 1
Scccber scombrus 0 O O O Il 1 Myoxocephalus spp. 0 0 0 0 Liparis opp. 0 0 0 0 Pseudopleuronectes 0 0 0 0 americanus 13.6 35.2 33.2 2.2 Total 6 - 20 5 - 130 1 - 169 0-7 ,
- Represents all three egg stages frac January through February.
** Represents all three egg stages from January through }! arch. +0.505 sa :ples only.
30
p - Tcble 3 (continued). Format: R ngc OCTOBER 1975 1976 1977 1978 1979 Cadidse-Clyptocephalus 0.8 0.2 1.3 0-2 0-1 0-5 cadidae* O O 1 0 0.7 Enchclyopus-Urophycis- 2.0 1.2 0 Pcprilus 0-8 0-3 Enchelyopus ciebrius** O O 16 0 6 Urophycis spp. 0 0 1 0 - 0. 7 1.ab r id ac-L i=and a 0 0 1
- Labridae . 0.1 0 0 0-1 Sccraber scombrus e 0 a 0 0 Paralichthys-Scophthalmus 0 = 0.3 2.5 0-2 0-8 w w ~
Total " 4 0 2 2 2 19 m m LARVAE
= x Clupea harengus harengus ~
0 0 0 0.8 < Enchclyopus ci::brius e 0 m 0 6 0 10 Tautogolabrus adspersus 0 0 0 Ulvaria subbtfurcata a 0 0 0 Pholis gunnellus 0 = 0 0 Ar: nod y te s s p. 0 0 0 Sember sembrus 0 0 0 ,I Hyoxocephaluo app. 0 , 0 0 i Liparts opp. 0 0 0 Pacudopicuronect 0 0 0 arne e t eanus 1.0 3.5 6.2 Total 0-2 0 - 15 2 - 13
- Represents all three egg stages fr m January through February.
*+2epresents all three esa stages frm January through }isrch.
31
Table 3 (continued). Tomat: Haan l Range hCVDGER 1975 1976 1977 1978 1979 Cadidac-Clyptocephalus 16 48 1 3 1 8 0 4 2 10 Cadidae* 2.8 1.0 2.2 11.0 3.8 1-6 0.4 - 2 0.5 - 5 1 - 26 0.9 - 7 Enchelyopus-Urophycis- 0.1 0.1 Pcpritus 0 0 0 0 - 0.6 0 - 0.5 Enchelyopus cimbrius** 0 0 0 0 0 0.5 Urophycis spp. 0 0 0 0 0 Lab r id ac-Limand a 0 0 0 0 0 Lab r idae 0 0 0 0 0 Secc.ber scombrus 0 0 0 0 0 ParniIchthys-Scophthalmus 0 ( 0 0 0 Total 32.5 2.6 20.3 13.0 10.6 18 - 51 1-4 2 - 13 2-7 4 - 17 , LARVAE Clupea harengus harengus 0.4 2.0 0.2 0.3 0 0-1 0-5 0 - 0.5 0 - 0.4 Enchelyopus cimbrius 0 0 0 0 2 0- 4 Tautogoinbrus adspersus 0 0 0 0.2 0 0-1 Ulvaria subbifurcata 0 0 0 0 0 Pholis gunnellus 0 0 0 0 0 A. racd y te s s p. 0 0 0 0 0 Sember scombrus 0 0 0 0 0 Hyoxoc.:phalus app. 0 0 0 , 0 0 Liparts opp. 0 0 0 0 0 Pseudopleuronect 0 0 0 0 0 americanus Total 0.7 0.1 2.0 3.0 0.6 0-1 0 - 0.4 0-5 2-5 0.4 - 0.9
*:lepresents all three eBS stages frce January through February.
- iepresents all theco egg stages frecs January through m i-h.
32 E m
Mean Table 3 (continued). Format: Range DECEFBER 1975 1976 1977 1978 1979 cadidae-clyptocephalus 0 0 0 0 0 I Cad id ac
- 6.7 1 - 12 0.9 0-3 2.3 1-3 2.8 1-6 4.4 3-8 I
Enchclyopus-Urophycis- 0 0 0 0 0 Pcprilus Enchelyopus cimbrius** 0 0 0 0 0 Urophycis app. 0 0 0 0 0 Lab r id ac-Limand a 0 0 0 0 0 Labridae 0 0 0 0 0 Seceber scombrus 0 0 0 0 0 Paralichthys-Scophthalcus 0 0 0 0 0 Total 6.7 0.9 3.7 2.8 4.5 0-3 2 - 10 1-6 3-9 I 1 - 12 LARVAE Clupea harengus harengus 1.8 0 0 5 0 2 Encaclyopus cimbrius 0 0 0 0 0-09 Tautogolabrus adsperous 0 0 0 0 0 Ulvaria subbifurcata 0 0 0 0 0 I Pholis gunnellus 0 0 0 0 0 Amod y te s sp. 0 0.6 0 0.1 9.8 0-1 0 - 0.4 0 - 24 Seceber scombrus 0 0 0 0 0 I Hyoxocephalus spp. 0 0 0 , 0 0 Liparis spp. 0 0 0 0 0 Pseudopleuronectes 0 0 0 0 0 americanus l Total 2.5 0.8 2.5 1.3 10.2 l 2-7 0-2 0-5 1-2 0-M
*!1epresents all three egg stages frca January through February. ** Represents all thrco egg stages frca January through March.
33
I I Il I i I I ! I; Figure 2: Mean monthly densities (per 100 m of water ) of I the numerically decinant fish larvae entrained at the Pilgrim tiuclear Power Station, January threugh Decc=ber, 1975-1979. I I I I I I I' , I 34
I I I 'O : l [ Clupea horenaus harenous l
........ 1975
_ - - - - - 1976 l
- 1977 l
_ 1978 1979 10 0 -- I % E Io O" Isx to - Ik - I v
~
D 14 Iw ~
/
I 1 -
- ,..- . . i ~
- l l
l . 1 I
. l .. : A ' * ' \
f ) s N' 1 I ' -' L ' o - JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC i MONTH l 35
I l [ Enchelyopus cimbrius
- .........iezs 3'
- - - - - 1976 1977 i
_ 1978 I 1979 l ico - E-E l _ l
~
m - e t l 8
~ Jl '. . ~
I \*. 4 [ s ;. * /
/ ', % to - \* /
2 I y \*. _ . s. / i
- - / V*
i Q -
)
- I
% . i 0 -
t . 4 ! .-
' E .- E . n l . . \
1 -
! *l g I
l I t g i t
~
JAN FEB MAR PR MAY JUN JUL AUG SEP T DEC MONTH 36 , g
'O O[ Tautogolabrus adspersus ' ;
l ~
........ 1975 - - - - - 1976 1977 I _
1978 1979 10 0 -- I _ E c - g~~,l lI Q - I \
\
A 10 - I e : . i I f ., 1
- I ., t Q -
- I '
t q - I
., I f
g - 1
~ I i l .i I 1 I l '.
I 1 _-
~
I
/ i *.
t _ l \ l -
!l I
g
~ . I I t * * } l l [ \ \ ' i JAN FEB MAR APR MAY JUN JUL AUG SEP I ==
OCT NOV OEC 37 '
l I I,
'
- bbifurcofa
{ U/varia
........ 1975 - - - - - 1976 1977 1978 1979 m g
10 0 -- g - . G ~ 9 - . W . . A 10 g _ . . s - . ( - l sj
.s l ~ i s ~
N : Q . - t -
~ - l -
- 1. I 1 8 ' ' _ _ _ m 'm m . m' o .f . .
JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC MONTH 38 - j
e e I l _ Pho//s cunnellus
.........i973 I -
_ _ ~- - - 1976 1977
- . 1978 1979 100 _
I m m m pump ImoG - o . Is - I ~x 10 - . . g - s _ v> - Iq - k .
~
N .
= _
I . 1 - m im cima M I _ I O I JAN FEB I MAR APR MAY JUN JUL AUG SEP OCT NOV OEC MONTH 39 I
l
- l t i 1
'0** ~ Ammodyles sg.
l _ ........ 1ezs _ - - - - - - 1976 ' 1977
-1978 1979 l
100 -- I e
- g m -
E o -
, gl Q _ .
- ' 1 Q * \
tu: . R A to -
- k ~ , .
4 5 e l
~
t - z - r
.: r s
l i - I
,== , ~ /
l
/
l 3
.- ~ /
s
, E. 1 l ' ' ' /
O ' I ' ' JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV OEC MONTH 40 - , Il
'O i
- Scomber scombrus i -
........ 1975 i - - - - - 1976 1977 1978 I
1
- 1979 4
10 0 - + ! = iI i m q e O l
- l t .
i k I* x to - AN -l Q - e k I I , s
~
I I I s
\
i I g
. \ *I t .' I t
l t .1 l
^
- I . 1 lI ; \
" .I * ,g .
- s *
~ .I .
- I 1 I
e
- o "
' I L'- - -
JAN FES MAR APR MAY JUN JUL AUG I == SEP OCT NOV DEC 41 I
l I
* ~ Myoxocephalus spp. ........ 1975 - - - - - 1976 l l
_ 1977 I 1978 l 1979 l too -- O E m - 6 - l 0 .- , S .- '. 5 4 A to - k - Di : . m Q
~
k . Q - E _ 1 .
. 4 ame - \ \ \ \ \
t 1
\
i ' ' ' ' ' ' f f f 1 -_ _ _ 3 JAN FEB MAR APR MAY JtJN JUL AUG SEP OCT NOV DEC g MONTH 42 - I
i 1000 -- Liparis spp. :
........ 1976 I
l
- - - - - 1976 l I 197 7 l - - {979 1978 l
I 10 0 -- I _ 9 Im 6 - o IO _ .l ' A 10 - s t
- .t k :
,I w R
N
.- i i
t. q -
\ *-
I .-
~
q
- n -
l \
% : \
I - l \
\
I ' = l ', 1 g l I
- s - l I - \
l
- \ \
I O I I I
\ \
JUN JUL AUG SEP OCT NOV DEC 'g JAN FEB MAR APR MAY MONTH E l 43
l
. ll, l
[ Pseudopleuronecte's americanus I
- ........ 1975 g
- - - - - 1976 1977 1978 l, 1979 I
100 -- 3 E
~ % _ E,l Ei o -
9 _ A 10 - k -
% - l ~~ E l .
1 l q - 1
~ '
k .' 3 - n : :
- E
- E
~ ~ * . a
- i,
\ ~ ' ; / . / \\
c < u , , , i...... t, , m JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV OEC g MONTH E u . l
l . e e l l
' '^' '^""^'
__m
- - - - - 1976 i g ~
1977 5 1978 1979 g .. ... .
~: ,co -
l
. l ,~~ ,
m
*t l
s'
- i
. . s G ~ *l e
l .. . .. . i m m i h
/ '
g , g e g - g i
~
N \
- w. t - :
l , -
~ \ \ \
i l -
\ \ \ ,
f
/
l
\ # \ j g / i / \1 l 0 a a a a a a MON 7*H A. a sie er ~6 occ 1
45
Table 4: Sary of nu=bers of smelt larvae entrained at Ph?S duri y; the months of April and May, 1974-1979. All densities are per 100 mb of water. 1974 1975 1976 1977 1978 1979 Su=ed c=elt densities 395 2 3.9 1123 3.5 4.5 Hu=ber samples taken 30 53 57 221 27 27 Mean 13.2 0.05 0.07 5.1 0.1 0.17 Highest density 97.2 1.0 1.0 65.9 1.7 1.1 Sampling period 4/24-5/25 4/1-5/27 4/29-5/7 4/1-5/27 4/3-5/3 4/5-5/29 Table 5: Mean, maxi =um, and =ini=um discharge (cf s) in the Jones River recorded at KinEston, Mass. by the U.S. Geological Survey
- for the months of April and May, 1974-1979.
1974 1975 1976 1977 1978 1979 April Mean 46.0 34.6 27.7 40.5 44.5 34.9 Maximum 84 75 44 87 82 62 Minimum 30 0 19 25 24 14 May Hean 33.3 18.8 21.6 33.4 48.2 50.2 Maximum 62 28 33 120 95 128 Minimum 18 11 16 14 19 22
*U. S.C. S. 19 75, 19 76, 19 7 7, 19 78, 1979. 1979 data - personal cortnunication.
I I-46
~ '
IV. LITERATURE CITED Ahlstrom, E.H. and R.C. Counts. 1955. Eggs and larvae of the Pacific hake Merluccius productus. U.S. Fish and Wildlife Service, Fish. Bull. 56(99): 295-329. Hardy, J.D. , Jr. 1978. Development of fishes of the mid-Atlantic Bight. An atlas of egg, larval, and' juvenile stages. Vol. II Anguillidae through I syngnathidae. U.S. Fish Wild 1. Serv. , Birl. Serv. Progr. , 458 pp. 1971. Comparative morphology and ecology of the pelasic larvae Khan, N.Y. I of nine cottidae (Pisces) on the northwest Atlantic and St. Lawrence drainage. Ph.D. thesis. Univ. Ottowa. 234 pp. Lawton, R.P. , E. Louloheras , P. Brady, and M. Borgatti. 1979. Progress report I on s: cit reproduction and spawning population structure in the Jones River run. ,In Boston Edison Company.1979. Marine Ecology Studies related to Semi-annual report 14 operation of Pilgrim Station. Marine Research, Inc. 1977a. Entrainment investigations and Cape Cod Bay ichthyoplankton studies, March-August 1977. 31 pp. and 78 pp. Appendix.
. 1977b. Entrainment investigations and Cape Cod Bay ichthyo-plankton studies, July-Septe=ber 1976. 69 pp. and 332 pp. Appendix. . 1978. Investigations of entrainment of ichthyoplankton at the Pilgrim Station and Cape Cod Bay ichthyoplankton studies, March-December 1977. Twelve-conth su==ary for 1977 Cape Cod Bay Ichthyoplankten Studies.
43 pp. and 180 pp. Appendix. Meyer, T.L., R.A. Cooper, and R.W. Langton. 1979. Relative abundance, behavior, and food habits of the A=crican sand lance, Ammodytes americanus, from the Gulf of Maine. Fish. Bull., U.S. 77: 243-253. Richards, S. W. , A. Perlmutter, and D.C. McAneny. 1963. A taxonomic study of the genus Amodytes from the east coast of North America (Teleostei: Ammod y te s) . Copeia l'363(2): 358-377. Sentt, J.S. 1003. Morphometries, distribution, growth, and maturity of off-I shore sand lance (Ammodytes dubius) on the Nova Scotia banks. Res. Board Can. 23: 1//3-1/oa. J. Fish 1972 Morphological and meristic variation in Northwest Atlantic I sand lances (Arcodytes) . ii. Fiah. Res. Board Can. 29: 1673-1678. U.S. Geological Survey. 1975. Water Resources Data for Massachusetts, New Hampshire, Rhode Island and Vermont. Part 1. Surf ace Water Records. Part 2. Water Quality Records. 429 pp.
. 1976. Water Resources Data for Massachusetts and Rhode Island -
Water Year 1975. Water data report MA-RI-75-1: 288 pp.
. 1977. Water Resources Data for Massachusetts and Rhode Island -
Water Year 1976. Water data report MA-RI-76-l: 300 pp. 47
. 1978 Water Resources Data for Massachusetts and Rhode Island '-
Water Year 1977. Water data report MA-RI-77-1: 299 pp. 1979. Water Resources Data for Massachusetts and Rhode Island - Water Year 1978. Water data report MA-RI-1: 299 pp. Winters , C.H. 1970. Meristics and Morphometrics of sand lance in the Newfoundland area. J. Fish. Res. Board Can. 27: 2104-2108. I I I 48 l
l
}
I I ' l Investigations of Larval Winter Flounder in the Plymouth Harbor-Duxbury Bay Estuary, I April - June 1979
- I I
Marino Research, Inc. I Falmouth, Massachusetts I I November 1, 1979 i I I 'I I I . I I -
i I ,
! Table of Contents Page
! Sumrnary - I. Introduction 1 a II. !!cthod s 1 A. Field Sampling 1 B. Laboratory Analysis 7 j C. Statistical Treatment 8 III. Results 8 Literature Cited 16
- I
- Appendix 17 1
i I i I I I ,I I I l I I l I . .
l Tab 1'es No. Page 1 Sampling station summary for the Plymouth liarbor-Duxbury Day flounder studies, 1976-1979 (* - stations sampled). 3
~
2 Comparison of population densitics of larval flounder entrained at PNPS during the spring of E' 5' 1976 through 1979, with estimates of larval standing stocks in the Plymouth Harbor-Duxbury Bay estuary. 9 3 Hean catch per 20-minute tow, 957. confidence limits (CL), and total number of tows (n) for Massachusetto Division of Marine Fisheries otter trawl stations 1 and 3, January-December, 1970-1978. 14 4 Hean catch per 20-minute tow, 957. confidence limits E (CL), and total number of tows (n) for Massachusetts 3 Division of Marine Fisheries otter trawl stations 1 and 3, January-October 1970-1979. 14 Appendix Table Al Larval winter flounder densities, per 100 m of water, estimated at cight stations in PHDB on four dates in 1979. 17 I I I I I I I I I
I Figures No. pog,
- g 1 Eight larval winter flounder rtations in Plymouth E Harbor-D"xhury Say (-) ===P t ed in 1976 and 1979-The remaining stations (o) were sampled in the 1976-1977 programs as indicated in Table 1. 2 2 Entrainment att:aapling station in PNPS discharge canal. 5 3 Massachusetts Division of Marine Fisheries otter trawl stations in the vicinity of PNPS. 6 4 Log-transformed (base c) mean 31 rval flounder population densities (nos/100 m ) and 95 percent
; confidence limits for each sa=pling date in Plymouth Harbor-Duxbury Bay for 1976, 1977, 1978, and 1979. 10 ,I 5 Log-transformed (basee)meanlarva3) population densities (numbers /100 mflounder , classified by developmental stage, for each sa.:pling date in Ply =outh Harbor-Duxbury Bay for 1976 through 1979. 11
- I
- 6 Mean adult winter flounder catch per 20-minute tow with 957. confidence interval for Massachusetts
.E Division of Marine Fisheries otter trawl Stations
- 5 1 and 3, January-October of each year 1970-1979. 15 t
I I lI I I I I I
5u:r.a ry 4
- 1. Sn.:pling was conducted for larval winter flounder (Pseudopleuronectes americanus) at eight stations in Plymouth Harbor-Duxbury Bay (PHDB) on four dates in 1979.
- 2. Larval densities, per 100 m of water, obtained in 1979 were compared with similar data obtained in 1976,1977, and 1978, and with inrval flounder densities recorded at the same respective times in the Pilgrim Nuclear Power Station (PNPS) discharge canal.
- 3. Larval flounder sampic densities suggest that the 1979 PHDB population was intermediate in abundance between the 1977 and 1978 populations.
I Over the 1976-1979 period PHDB densities were lowest in 1976, highest i in 1978.
- 4. Larval flounder densities observed in the PNPS discharge canal were quite low compared with P3DB densities recorded on corresponding dates. Den-sities at both locations appear to vary independently of one another.
- 5. Adult winter flounder catch per tow near PEDB based on Massachusetts Division of Marine Fisheries otter trawl data collected from 1970-1979 suggests a decline in flounder populations from 1970 through 1975 and a period of increasing abundance from 1976 through 1979.
- 6. Although four years (1976-1979) are insufficient to identify a relation-ship between PHDB larval populations and nearby adult populations, there is some suggestion that they cay parallel one another. This is suggested by the fact that, among these four years, 1976 was the lowest year for I
1978). I I
1 1
- 7. The low number of larval flounder entrained by the PNPS relative to the
- numbers observed in PHDB, the fact that larval densities in PIDB in-l creased durin;; the 1976-1979 period, and that adult flounder in the area i appear to be in a period of increasing abundance, all suggest to us that PNPS has no detectable adverse impact on the local flounder populations.
E' ! I I I k I I I I I l' I I I I
I 1. IffTP.0DUCTIO!1 'I This report discusses results of larval winter flounder (Pseudopicuro-nectes americanus) sampling concucted in the Plymouth !! arbor-Duxbury Bay es-tuary (PHDB) on four dates in the spring of 1979. Larval flounder densitics, 3 per 100 m of water, recorded on these dates are presented and compared with similar data obtained in 1976,1977, and 1978. Densitics obtained in PHDB are compared with entrainment rates recorded on the same dates at the Pilgrim liucicar Power Station (FUPS). Finally, larval flounder abundance estimates from PHDB are considered together with trends in abundance of adult winter flounder recorded by the Massachusetts Division of Marine Fisheries. The work ccepicted in 1979 was conducted under Doston Edison Company Purchase Order !:o. 64101 dated March 2,1979. I II. a L vDS I A. Field Sampiing Figure 1 shows the eight stations in PEDB sampled in 1978 and 1979 as well as the 23 and 12 stations sa= pled in 1976 and 1977, respectively. Tabic 1 su=r.arizes the stations sampled each year. The eight 1978-1979 stations were selected as those which in 1976 and 1977 best approximated the population means derived from all stations, using 1 cast squares meth-1 I ods. Eight was the maximum number of stations which could be sampled in l l triplicate by one vessel within a four-hour period of the ebb tide, be-ginning one hour af ter high water cnd ending one hour before low water; l this time requirement was established for previous years' sampling. ^ I Sampling methods were identical to those used in 1976, 1977, and 1978.
, Oblique tows were =ade at each station on four dates using a 3/4-m Tucker I
I -'-
~
I I I-, f.i O 21 l DUXBURY BAY O CAPE COO BAY '
.:: 20 ,- O gg :: ,
Og g
- - ' . , . ::,- 0 23 0 18 ',:.
e t2 "' ' 014 17 0 f Og3 el5 ,': eso O g g M l *It e6 07
- PLYMOUTH
- a,z 05 40 BIGHT I
'. :. O3 g PEYMOUTHe g HARBOR 9
- v. .
II * *- 10
*:::. ROCKY PT * * .*:',3.'l.,* . a. .:' . ,, . 4,. . . . . . . . f,; . f., , . . ..:.
PN PSM.:.
- .. g .. .
N
* " '.& ~ :-l e
t i
~
- .[:
~,
E f N A U T. M !. .' : - . g t'igure 1: Eight larval winter flounder stations in Plymouth Harbor-Duxbury Bay (e) sampled in 1978 and 1979. The remaining stations (o) were sampled in the 1976-1977 programs. I I
- ~--
I
i I l Table 1: Sampling station su:r.arv f or the Plymouth liarbor-
- l
- n Duxbury Bay flounder studies, 1976-1979 (* - stations sampled).
I
- Station 1976 1977 1978 1979
! 1 *
- 2 * * *
,I 3
- i i
5 *
- 6 * * * * ,
l 7
- 4 '
- 8 *
- 9
- 10 * * *
- 11 * *
- i 12 * * *
- 13
- 14 *
- I 15 * * *
- 4 16
- 17
- lE E 18 * * *
- 19 * *
- 20
- 21
- 22 * * *
- 23 * )
1 I 1
- I I
lI l I l I
net (1:arinc Researc!.,1:.c. pattern) made with 0.333-m Nitex mesh. Tows I were a minimum of five minutes in length. In most cases, because the sampling stations were in very shallow water, the net was lowered and hauled back several times to make up the necessary towing time. Towing speed was maintained at 2 to 2.5 knots. Filtration volumes were deter-mined with a Cencral Oceanics model 2030 digital flowmeter mounted in the 3 mouth of the net. Volumes averaged about 115 m per tow. Sampling in PHDB was coordinated with entrainment sampling at PNPS so that estimates of larval flounder densities at both locations could be compared. Discharge samples were collected on the same dates PHDD was sampled by streaming a 0.333-m mesh, 60-cm plankton net i- the discharge canal. Rigging for these sampics was located approximately 30 m down-stream of the discharge canal headwall (Figure 2). Sa=ples were collected in triplicate at low tide during daylight for six to ten minutes depending upon clogging rate of the net. A minimum of 100 m of water was filtered in each case. A Ceneral Oceanics 2030 flowmeter mounted in the mouth of the net provided volume estimates. The entrainment sampling program for the months of January-July 1979, the period which includes the winter flounder spawning season, vm 7 surr.arized in detail in MRI (1979). All field sa ples were preserved in a 10 percent solution of formalin l in seawater and returned to the laboratory for analysis . Trends in abundance of adult winter flounder were examined and com-pared with PHDB larval flounder data. Adult CPUE data for 1970-1979 were obtained from the Massachusetts Division of Marine Fisheries (BECO, 1978; Robert Lawton, personal cocr.unication) which regularly completes atter trawl tows near PNPS (Figure 3); in general duplicate 20-minute tows are " 8
L l " l L_ 1 F L , CAPE COD BAY e '..
.f*
- w..
*t l '. DISCH ARGE CANAL .4.,
BRIDGE N aC IN T 4gg
)k A Sty a ..gw;.
HEADWALL . *o. O. :.o. [ UNIT 1 INTAKE -
;m..
PNPS : . . ;,:.. e ICHTHYOPLANKTON '. . ' t UNIT 1
- STATION I i 100 METERS p elgure 2: Entraint.cnt sa:npling station in PNPS discharge canal.
7 _U
I i t 70*38' \ O E a
- u. T 4
y.
- N c,- n. e 5 ~~oo' N O h O g
PL YMOUTH @ BAY 7A
.%- l 1.% / %.. .
I
%,e+ /'S Q = %[1 .,,}i'M- & h* * ,.y:.,e. '. b.,nr: C04 4-t# *}m ,'& ,'.% s k
p.-~" iMf' M PILGRIM j 9: N ~. NUCLEAR i dj POWER STATIO
'brIFg,gggg' Mcncenet Pt.
TR AWL STATIONS y, .. ,
,.31 1 1Q 1.85 Kilometers 0 1.85 3.70 T'- *p;i. , I lh *. -s *4: t 1 0 l' 2 7,g Nautical Miles -(
Figure 3: Massachusetts Division of Marine Fisherica otter trawl stations in the vicinity of PNPS. (Figure reproduced from BECO 1978, ; page 111.4-5). I
I made at cach station twice per month. Only Stations 1 and 3 were considered here because Station 2 data were missing for July through September of 1978 due to the abundance of lobster gear in that area. ; l I B. Laboratory Analysis l Larval winter flounder from both PIIDB and the PNPS discharge col-lections were classified into the following developmental stages; an approximate length range for each stage is included. Stage I - Frce hatching until the yolk sac is fully absorbed. 2.3-2.8 r:n TL. Stage II - From the end of stage I until a loop or coil forms in the gut. 2.6-4.0 en TL. Stage III - From tl.c end of stage II until the left eye migrates past the midline of the head during transfomation. 3.5-8.0 nn TL. Stage ~V - From the end of stage III to juvenile stage. 7.3-8.2 rn TL. I Entire samples were counted except when larval flounder were par-ticularly abundant. In those cases aliquot subsamples were taken using a plankton splitter. The contribution of subsampling error to total sampling error from all sources is generally not large (MRI, 1974) and may be kept at a low level if the number of specimens in an aliquot increases as the aliquot fraction grows smaller (e.g., 100 larvae should be present in a 1/2 split, 200 in a 1/4 split, etc.). Representative specimens of each stage have been catalogued in our reference collection. I l
C. Statistical Treatment I Confidence limits (p = 0.05) for the mean population estimates of I larval flounder in PHDD for each year 1976 through 1979 were calculated using logarithmically transformed data, a standard procedure when untrans-f ormed data depart markedly from the normal distribution, as plankton data typically do (see any standard text, e.g., Zar, 1974). !;ote that back-transformations of logarithmic values will frequently give estimates of the population mean which dif fer somewhat from the arithmetic mean of untransformed data and confidence limits which are not symmetrical about the mean. III. PlSULTS I 3 Larval flounder densities, per 100 m of water, computed for each date, station, replicate, and developmental stage are tabulated in Appendix Table Al. 3 Mean densitics, per 100 m , calculated over the eight stations are sta=arized by date in Table 2 along with a corresponding estimate of the PIDB stock size based on those data. Also included in Table 2 are mean density estimates for each date from the PleS discharge canal. The acan densities from P!!PS were multiplied by the plant pumping rate. for each respective date to provide an estimate of the number of larval flounder entrained in 24 hours. Similar data for the 1976-78 seasons are included for comparison. lican densitics of log-transformed (base c) data f rom P10B together with corresponding 957. confidence limits were plotted for each year, 1976-1979, in Figure 4 Table 2 and Figure 4 suggest that the 1979 larval flounder populations in PIDB were intermediate in abundance between the 1977 and 1978 populations, I . l thus the upward trer.d in larval flounder densities noted from 1976 to 1978 I
M M M M M M M M M M M M m M M M M M Tabic 2: Comparison of population densities of larval flounder entrained at PNPS during the opring of 1976 through 1979, with estimates of larval standing stocks in the Plymouth liarbor-Duxbury gay 3 estuary. Standing stock estimates are based on a half-tide volume for the estuary of 9.077 x 10 m. Mean 11 umber Mean density in Plymouth liarbor- - Pumping density at entrained Plymouth liarbor- Duxbury Bay rate (cfs) Pilgrim 3 in24grs Duxbury Bgy stock size 7 Date (no/100 m ) (x 10 ) (no/100 m ) (x 10 ) 1976 Apr 29 345 19.26 (n=21) 1.63 21.69 (n=19) 1.97 thy 3 345 6.97 (n=15) 0.59 31.03 (n=15) 2.82 May 13 345 37.64 (n=12) 3.18 41.27 (n=24) 3.75 May 17 345 99.07 (n=9) 8.37 46.25 (n=23) 4.20 June 1 690 7.93 (n=45) 1.34 19.28 (n=19) 1.75 1977 Apr 28 690 15.08 (n=72) 2.55 72.30 (n=23) 6.56 May 4 690 4.84 (n=71) 0.82 85.64 (n=36) 7.77 h liny 12 69 16.17 (n=72) 2.50 3 7.17 (n=36) 3.37 0 rs) June 1 690 15.89 (n=72) 2.68 10.26 (n=36) 0.93 1978 Apr 18 690 0.55 (n=3) 0.09 276.21 (n=24) 25.07 May 2 345 4.50 (n=3) 0.38 135.79 (n=24) 12.33 Itay 18 690 33.98 (n=3) 5.74 63.74 (n=23) 5.79 May 31 690 0.31 (n=3) 0.05 7.61 (n=24) 0.69 1979 Apr 13 690 0 (n=3) 0 77.17 (n=24) 7.01
!!ay 4 690 13.02 (n=3) 2.20 85.80 (n=24) 7.79 Ilay 14 345 16.09 (n=3) 1.36 116.66 (n=24) 10.59 June 4 690 27.07 (n=3) 4.57 5.30 (n=24) 0.48
I
- 1976 l i
o 1977 E 1978
+ 1979 I
6-I A. k Es
's, 5 - 's 's I
T B its - ts - l +1 _ _ _. _ _ _ _ , _ _ _w 6-
N M omm mehN 0000 e y y
- e N e e e e e e & y l
j y , A mh o mmme m 4 enem Nmme m 9 d e L J in h N o esem o e o e u. e e e. . O. d emM
~em. ~ ~m e e e e 3000 h.
m 4 T emee mmme m 9.. w 40 m I 7" k i emde NOch
- EON N g 3 O e e e o Omme OOom o a Z = n*NN h* * * ~8 h 4 emFN e e . O em e Cb J 2 dh ad hamw - o e OM
- A 2 M 1 m 34*m ehem * *
- e O 2 4 W 4 mamm CNNe OOOO e a *wk"K b
- e e e e 44Nm e -
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I I !I l I IMPINGEMENT OF ORGANISMS AT PILGRIM NUCLEAR POWER STATION I (January - December 1979) I Prepared by: e 9 fA Robert D. Anderson I Senior Marine Fisheries Biologist Approved by: Dr. F. J. Mogolesko Environmental Sciences Group Leader I I I I Nuclear Engineering Department I Boston Edison Company 800 Boylston Street Boston, Massachusetts 02199 i j l April 1980 l l l I
4 lI \ l TABLE OF CONTENTS 1 lI i Page lg Section Title ) i n 1
SUMMARY
I !I i 2 INTRODUCTION 2 !I j 3 METHODS AND MATERIALS 3 l l 4 RESULTS AND DISCUSSION 6
! 4.1 Fishes 6 4.2 Invertebrates 17 l
ll 3 CONCtuSIONS n 6 LITERATURE CITED 23 lI lI !,I !I il I ii e , e - ,. ,
LIST OF FIGURES I Figure Page I 1 Location of Pilgrim Nuclear Power Station 3 2 Intake Structure Pilgrim Nuclear Power Station 4 3 Length-Frequency Histogram for Atlantic Silversides Impinged at Pilgrim Station, January-June 1979 9 I 4 Day / Night Impingement Rate for Atlantic Silversides I and Intake Water Temperature at Pilgrim Station, January-June 1979 12 5 Trends of Intake Water Temperature, and Number of Fish Captured by Month from Pilgrim Station Intake Screens for the Five Most Abundant Species Collected, January-December 1979 15 I I I I I I 1 I 1 I m
I LIST OF TABLES I Tcble Page, I 1 Monthly Impingement for All Fishes Collected From Pilgrim Station Intake Screens, January-December 1979 7 2 Species, Number, Total Length (mm), Weight (gms) and Percentage for All Fishes Collected From Pilgrim Station Impingement Sampling, January-December 1979 8 3 Percent Composition of Fishes for High Impingement Dates I at Pilgrim Station During March & April 1979. Catch /Hr. by Species in Parentheses. 10 4 Annual Impingement Collections (1973-1979) for the 10 Most Abundant Fishes From Pilgrim Station Intake Screens During January-December 1979 11 5 Approximate Number and Cause for Major Fish Mortalities at Pilgrim Nuclear Power Station, 1973-1979 14 6 Impingement Rates per Hour, Day and Year for All Fishes Collected From Pilgrim Station Intake Screens During January-December 1979, Assuming 100% Operation of Pilgrim Unit 1 16 7 Monthly Means of Intake Temperatures ( F) Recorded During Impingement Collections at Pilgrim Nuclear Power Station, 1976-1979 18 E
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8 Monthly Impingement for All Invertebrates Collected From Pilgrim Station Intake Screens, January-December 1979 19 I IV I Il
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SECTION 1 SWY I Fish impingement averaged 3.24 fish / hour during the period January-December 1979. Atlantic silversides (Menidia menidia) accounted for 73.3% of the fishes collected. Rainbow smelt (Osmerus mordax), windowpane (Scophthalmus aquosus), pollock (Pollac_hius virens) and winter flounder (Pseudopleuronectes americanus) accounted for 5.4, 2.9, 2.3 and 2.1%, respectively, of the fish impinged. Peak impingement periods occurred in March and April and involved I Atlantic silversides as was true in previous years when February was also a high impingement month for this species. At full-load yearly (January-December) operation of Pilgrim Nuclear Power Station (PNPS) the estimated maximum impingement was 28,280 fishes (1,095 lbs.). The PNPS capacity factor was 84.4% from January-December 1979. I The collection rate (no./hr.) for all invertebrates captured from January-December 1979 was 18.44. The blue mussel (Mytilus edulis), sand shrimp (Crangon septimspinosa), jellyfish (Aurelia auritia) and common starfish . (Asterias forbesi) accounted for 92.2, 2.3, 1.2 and 1.1%, respectively, of the l invertebrates impinged. Mixed species of algae collected on intake screens amounted to 565.2 pounds. I I l l I ! l l I I I
I SECTION 2 I INTRODUCTION I Pilgrim Nuclear Power Station (lat. 41'56' N, long. 70 34' W) is located on g the northwestern shore of Cape Cod Bay (Figure 1) with a licensed capacity of 5 655 MWe. The unit has two circulating water pumps with a capacity of approx-imately 345 cfs each and five service water pumps with a combined capacity of 23 cfs. Water is drawn under a skimmer wall, through vertical bar-racks spaced approximately 3 inches on center, and finally through vertical travel-ling water screens of 3/8 inch wire mesh (Figure 2). There are two travelling water screens for each circulating wat'er pump. This document is a report pursuant to operational environmental monitoring and reporting requirements of NPDES Permit No. 0003557 (EPA) for Pilgrim Nuclear Power Station, Unit I. The report describes impingement of organisms carried onto the vertical travelling water screens at Unit I. It presents analysis of the relationships between impingement, environmental factors, and plant oper-ational variables. The report is based on data collected from screen wash samples from January-December 1979. I I I I I I-I
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I SECTION 3 METHODS AND MATERIALS Three screen washings each week were performed from January-December 1979 to provide data for evaluating the magnitude of marine biota impingement. The total weekly collection time was 24 hours (three separate 8-hour periods: morning, afternoon and night). Two collections represented dark period sampl-ing and one represented light period sampling. At the beginning of each collection period, all four travelling screens were washed. Eight hours later, the screens were again washed (minimum of 20 minutes each) and all organisms collected. When screens were being washed continuously, half hour . collections were made at the end of the regular sampling periods, and they represented two light periods and one dark period on a weekly basis. I Water nozzles directed at the screens washed impinged organisms and debris I into a sluiceway that flowed into a trap. The trap was made of galvanized screen (3/8-inch mesh) attached to a removable steel frame. Variables recorded for organisms were total numbers, and individual lengths (mm) and weight (gms) for up to 20 specimens of each species. A random sample of 20 fish or invertabrates was taken whenever the total number for a species exceeded 20; if the total collection for a species was less than 20, all were measured. Intake seawater temperature, power level output, tidal stage, number of cir-culating water pumps in operation, timet of day and date were recorded at time of collections. The collection rate (#/ hour) was calculated as number of organisms impinged per collecting period divided by the total number of hours in that collecting period. All common and scientific names in this report follow the American Fisheries Society (1970) and Smith (1964). I I I
I SECTION 4 I RESULTS AND DISCUSSION 4.1 Fishes In 494.25 collection hours, 1,600 fishes of thirty-six species (Table 1) were collected from Pilgrim Nuclear Power Station intake screens from January-December 1979. The collection rate was 3.24 fish / hour. Atlantic silversides (Menidia menidia) were the most abundant species accounting for 73.3% of all fishes collected (Table 2). Rainbow smelt (Osmerus mordax), windowpane (Scophthalmus aquosus), pollock (Pollachius virens) and winter flounder (Pseudopleuronectes americanus) accounted for 5.4, 2.9, 2.3 and 2.1% of the total number of fishes collected and identified to lowest taxon. Atlantic silversides occurred predominantly in all monthly samples from March through May with the largest number (815) captured in April. Hourly collec-tion rates for Atlantic silversides ranged from 0 to 42 specimens. Silversides impinged in March and April accounted for 71.1% of all identified fishes cap-tured in impingement collections from January-December 1979. The majority of Atlantic silversides ranged from 100-125 mm total length (Figure 3), averaged 6 grams in weight and were mature specimens. Four high impingement periods for Atlantic silversides occurred during March and April when this species represented the great majority of the collections, and hourly rates varied from 8.9 to 24.1 on each date (Table 3). It is not unusual for silversides to , dominate the impingement catch the first 6 months of any year and a review of historical data shows they are generally one of the dominant species collected on an annual basis (Table 4). Although silversides were general 1</ consistently impinged more at night (Figure l l 4), analysis of variance (ANOVA) of diurnal effect on the impingement rate of Atlantic silversides from January-June 1979 demonstrated a statistically insignificant (p> 0.05) difference between rate of impingement during dark or nighttime hours as compared to daylight hours. No significant influence on I ___ _ _ _ _ __ . ._ . _ ._ _. ___m _ . _ _ _ _ .. __ Table 1. Monthly Impingement For All Fishes Collected From Pilgrim Station Intake Scre g January - December 1979 Species Jan. Feb. Har. Apr. Hay June July Aug. Sept. Oct. Nov. Dec. Totals Atlantic silverside 2 8 322 815 22 1 3 1.173 rainbow smelt 8 30 16 6 3 2 1 21 87 windowpane 9 29 5 3 46 pollock 8 21 7 4 2 39 winter flounder 1 1 10 17 4 1 34 Atlantic toncod 1 6 17 1 2 3 30 alewife 3 10 7 2 1 1 4 28 three-spined stickleback 8 15 2 1 26 cunner 2 2 2 7 6 1 2 22 blueback herring I 18 1 20 grubby 2 2 3 2 1 4 14 Atlantic herring I 8 1 2 1 13 northern pipefish 1 1 6 8 Atlantic menhaden i 2 4 7 butteriish I 5 1 7 fourspot flounder 5 5 American sand laneg 2 1 1 4 L' lausp fi s h 1 1 I I 4 Atlantic cod 1 I I 3 hake sp. I 2 3 little skate 1 2 3 radiated shanny 2 1 3 scup i 2 3 Alosa r.p. 2 2 longhorn sculpin 2 2 northern puffer 1 I 2 northern searobin 2 2 tautog i I 2 American eel I I Ammodytes sp. I l black sea bass I I ocean pout i 1 redfish 1 1 reil hake i I striped searchin 1 1
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l Totals 15 39 %7 969 81 .I 'l 3 Il 15 5 9 53 1,600 Collection Time (hrs.) 5.50 8.0 61.50 99.0 86.0 55.75 21.0 15.50 17.50 21.0 12.0 71.50 494.25 Collection Rate (#fhr.) 2.73 4.88 5.97 9.79 0.94 0.59 0.14 0.71 0.40 0.24 0.75 0.74 3.24
Table 2. Species, Number, Total Length (on), Weight (gms) and Percentage For All Fishes Collected From Pilgrim Station Impingement Sampling, January - December 1979 ___ Length Mean Weight Mean Percent of Srecies Number Range Length Range Weight Total Fish Atlantic silverside 1,173 70-162 110 2-19 6 73.3 rainbow smelt 87 73-220 126 2-52 12 5.4 windowpane 46 33-275 112 1-237 48 2.9 pollock 39 32-185 72 1-64 6 2.3 winter flounder 34 102-410 223 11-908 192 2.1 Atlantic tomcod 30 40-246 111 1-113 20 1.9 alewife 28 67-201 109 2-59 11 1.8 three-spine stickleback 26 32-78 64 1-7 3 1.6 cunner 22 55-218 139 2-196 60 1.4 blueback herring 20 65-170 97 2-15 7 1.3 grubby 14 58-145 87 3-39 11 41 Atlantic herring 13 40-315 183 0.4-287 66 northern pipefish 8 108-202 146 1-3 2 Atlantic menhaden 7 233-255 245 100-310 200 butterfish 7 31-138 63 1-43 10 fourspot flounder 5 273-376 320 159-417 254 i American sand lance 4 155-195 172 10-15 12 i' lumplish 4 25-71 52 1-15 8 " Atlantic cod 3 39-178 106 1-54 21 hake sp. 3 90-115 102 5-8 6 little skate 3 320-470 417 178-936 553 radiated shanny 3 99-126 111 7-13 11 scup 3 50-345 150 - - Alosa sp. 2 75-85 80 3-5 4 longhorn sculpin 2 340-359 350 420-454 437 northern puffer 2 85-248 167 10-321 166 northern searobin 2 211-270 241 84-187 136 tautog 2 95-205 150 13-181 97 American eel 1 305 305 48 48 black sea bass 1 256 256 152 152 ocean pout 1 585 585 686 686 redfish 1 133 133 41 41 red hake 1 90 90 4 4 Ammodytes sp. I 179 179 15 15 striped searobin 1 102 102 12 12 white perch 1 258 258 293 293 M M M M M M M M M M M M M M
i 100 l r 75 - E g N = 383 5 I a 2 50 - l 1 25 - 0 I 25 I 50 75 100 125 I 150 175 TOTAL LENGTH IN MILLIMETERS Figure 3. Length-Frequency Histogram for Atlantic Silversides Impinged at Pilgrim Station, January - June 1979.
Table 3. Percent Composition of Fishes For High Impingement Dates at Pilgrim Station During March & April 1979. Catch /Hr. by Species in Parentheses. 1979 Date Species 3/3 3/10 4/9 4/23 Atlantic silverside 95.7%(22.0) 85.9%(8.9) 96.4%(21.1) 96.2%(24.1) rainbow smelt 0.3%(0.06) windowpane 3.7%(0.4) 0.3%(0.06) 0.5%(0.1) pollock 0.5%(0.1) winter flounder 4.3%(1.0) 3.7%(0.4) 1.8%(0.4) Atlantic ~tomcod 0.7%(0.1) threespine stickleback 2.1%(0.5) g alewife 0.7%(0.1) 0.3%(0.06) g blueback herring 0.7%(0.1) 0.3%(0.06) 0.5%(0.1) Atlantic herring 0.7%(0.1) grubby 0.7%(0.1) cunner 0.7%(0.1) American sand lance 1. 8%(0. 2) hake sp. O.7%(0.1) northern pipefish 0.3%(0.06) ocean pout 0.5%(0.1) I I I l l I I e - - o
Table 4. Annual Impingement Collections (1973-1979) For the 10 Most Abundant Fishes From Pilgrim Station intake Screens During January - December 1979 Number of Impinged Fishes Collected From January - December I Species 1973 1974 1975 1976 1977 1978 1979 Totals Atlantic silverside 515 4 107 114 473 722 1,173 3,108 rainbow smelt 291 34 6 103 273 631 87 1,425 windowpane 24** 13 29 4 46 116 pollock 12 3 42 23 39 119 winter flounder 25** 1 4 29 64 34 34 191 Atlantic tomcod 1 63 157 31 30 282 alewife 894* 380* 42* 2,061 15 131 28 3,551
, three-spine stickleback 18 1 4 9 26 58 p cunner 99 10 28 285 154 61 22 659 8 blueback herring 894* 379* 41* 23 19 64 20 1,440 Totals 2,773 811 228 2,734 1,211 1,687 1,505 10,949 Collection Time (hrs.) 2,096.0 1,464.0 1,336.0 2,022.0 1,515.0 1,442.0 494.25 10,369.25 Collection Rate (#/hr.) 1.32 0.55 0.17 1.35 0.80 1.17 3.05 1.06 *llerrings indentified as a general category in 1973 - 1975 were split between alewife and blueback herring. ** Flounders identified as a general category in 1973 were split between windowpane and winter flounder.
1 No collections were made from March - July 1974. 2 No collections were made in September 1977.
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l l fish impingement could be attributed to tidal stage (impingement rate slightly I greater around high tide), water temperature or number of circulating water pumps operating (during most of this 6-month period both pumps were in operation). The Atlantic silverside impingement mortality in March and April 1979 was the ninth most notable fish kill at Pilgrim Station since operation commenced (Table 5). Of the nine fish incidents most (5) have involved impingement as the causative agent. However, at least in two of these the possibility of pathological influence has been implicated as indirectly contributing to the mortalities. They were the Atlantic herring (tubular necrosis) and rainbow smelt (piscine erythrocytic necrosis) incidents in 1976 and 1978, respectively. In January, February and December 1979, rainbow smelt showed numerical domi-nance in impingement. Although a repeat of the December 1978 mortality was not apparent, this species was second only to Atlantic silverside in collec-t'ans. While rainbow smelt abundance in 1979 might be anticipated by past impingement records as shown in Table 4, windowpane, pollock and winter flounder relative abundance was atypical. The species which have been among the dominant in most years (e.g., cunner (Tautogalabrus adspersus), Clupeid spp.) were conspicuously low in sample collections. This may be partially reflective of population variances for these latter species or the fact that the fewest sampling hours in 1979 occurred when they were most prevalent, as a I result of continuous screen washes, thus indicating a sampling bias. Monthly impingement rates for the five dominant species are illustrated in Figure 5. Projected fish impingement rates were calculated assuming 100% operation of Pilgrim Nuclear Power Station during the period January-December 1979. Table 6 presents hourly, daily and yearly impingement rates for each species cap-tured (rates are rounded ta significant figures). For all fishes combined the respective rates are 3.24, 77.69 and 28,280. The yearly rate of 28,280 fishes l "" impinged is approximately 23% less than the 5-year (1973-1977) mean annual !l projection of 36,734 fishes from the Marine Ecology Studies Final Report Related to Operation of Pilgrim Nuclear Power Station, Section IV (Marshall, 1978). A total of 61.78 pounds of fishes was collected from January to December 1979 which projected for 100% operation of Pilgrim Station amounts to 1,095 pounds. I 1
)
Table 5. Approximate Number and Cause for Most Notable Fish Mortalities at Pilgrim Nuclear Power Station, 1973-1979 . Date Species Number Cause April 9-19, 1973 Atlantic Menhaden 43,000 Gas Bubble Disease August / September, 1973 Clupeids 1,600 Impingement April 2-15, 1975 Atlantic Menhaden 5,000 Gas Bubble Disease August 2, 1975 Atlantic Menhaden 3,000 Thermal Stress August 5, 1976 Alewife 1,900 Impingement November 23-28, 1976 Atlantic Herring 10,200 Impingement August 21-25, 1978 Clupeids 2,300 Thermal Stress December 11-29, 1978 Rainbow Smelt 6,200 Impingement March / April, 1979 Atlantic Silverside 1,100 Impingement l l l l JANUARY FEBRUARY MARCH APRIL MAY JUNE JULY AUGUST SEPTEMBER OCTOBER NOVEMBER DECEMBER 80 - WATER TEMPE'R ATURE - 60
^ - # N' l
60 - 50 3 40 - - 40 3>
, WINTER FLOUNDER ,
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- D I POLLOCK i r
- 10 - 10 s a c 0 - 0 m .W INDOWPANE ,
- 15 5 k 15 7 j E 5 0
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- c -
0- 0 i JANUARY FEBRUARY MARCH APRIL MAY JUNE JULY AUGUST SEPTEMBER OCTOBER NOVE MBE R DECE MBE R i i 1 l l Figure . Trends of Intake Water Temperature, and Number of Fish Captured by Month from Pilgrim ] Station Intake Screens for the Five Most Abundant Species Collected, January - December 1979. l l
Table 6. Impingement Rates Per Hour, Day and Year For All Fishes Collected From Pilgrim Station Intake Screens During January - December 1979, Assuming 100'% Operation of Pilgrim Unit 1* Dominant Season Species Rate /Hr. Rate / Day Rate / January-December 1979 Of Occurrence Atlantic silverside 2.37 56.96 20,733 March - May rainbow smelt 0.18 4.22 1,536 December - February windowpane 0.09 2.23 813 tiarch - May pollock O.08 1.89 689 April - June winter flounder 0.07 1.65 601 March - May Atlantic tomcod 0.06 1.46 530 March - April alewife 0.06 1.36 495 April - May three-spine stickleback 0.05 1.26 460 March - April cunner 0.04 1.07 389 August - foptember blueback herring 0.04 0.97 354 April grubby 0.03 0.68 247 December Atlantic herring 0.03 0.63 230 April northern pipefish 0.02 0.39 141 December Atlantic menhaden 0.01 0.34 124 November - December i butterfish 0.01 0.34 124 September f fourspot flounder 0.01 0.24 88 June American sand lance 0.008 0.19 71 March - April . lumpfish 0.008 0.19 71 November - January Atlantic cod 0.006 0.15 53 April - June hake sp. 0.006 0.15 53 March - April little skate 0.006 0.15 53 June radiated shanny 0.006 0.15 53 May scup 0.006 0.15 53 September Alosa sp. 0.004 0.10 35 April longhorn sculpin 0.004 0.10 35 April northern putfer 0.004 0.10 35 May/ September northern searobin 0.004 0.10 35 June tautog 0.004 0.10 35 April - May American eel 0.002 0.05 18 November black sea bass 0.002 0.05 18 July ocean pout 0.002 0.05 18 April redfish 0.002 0.05 18 June red hake 0.002 0.05 18 May Ammodytes sp. 0.002 0.05 18 December striped searobin 0.002 0.05 18 December white perch 0.002 0.05 18 May Totals 3.24 77.69 28,280
- Rates have been rounded to significant figures.
m m a m M M M M M
I I Comparison with fish impingement rates at other power plants in the northeast United States shows Pilgrim Nuclear Power Station to be relatively low in this area of impact. Anderson et al. (1975) documented higher annual impingements at seven other northeast power plants in the early 1970's. Maine Yankee Atomic Power Company (1978) Nuclear Generating Station had a mean impingement rate of approximately 58 fishes /hr. from late 1972 - late 1977 while over the same period of time Pilgrim Station's rate was slightly greater than 2 fishes /hr. In a survey of estuarine and coastal power plants in the United States, Stupka and Sharma (1977) showed annual impingement rates at numerous locations for dominant species, and compared to these even expanded rates at Pilgrim Station (assuming 100% annual operation) were lower than at most other sites. I Intake water temperatures recorded during impingement periods at Pilgrim Station were generally lower in 1979 than the comparable mean monthly temper-atures for the interval 1976-1979 (Table 7). .In contrast, 1976 displayed relatively warm water temperatures, and 1977/1978 were average years. Pilgrim Station intake temperatures approximate ambient water temperature. These yearly differences in water temperatures may partially explain the dominance of some colder water species (e.g., windowpane, pollock and winter flounder) in collections in 1979, and warmer water species (e.g., cunner and alewives) in 1976. 4.2 Invertebrates l In 488.75 .cl.ection hours, 9,014 invertebrates of twenty-eight species (Table l 8) were collected from Pilgrim Station intake screens from January-December I 1979. The lection rate was 18.44 invertebrates / hour. Four species, blue l mussel (Mytilus edulis), sand shrimp (Crangon septimspinosa), jellyfish l (Aurelia auritia) and common starfish (Asterias forbesi) accounted for 92.2, 2.3, 1.2 and 1.1%, respectively, of the total number of invertebrates l collected. L 1 i b l l r L l
I I' Table 7. Monthly Means of Intake Temperatures (*F) Recorded During Impingement Collections 3 at Pilgrim Nuclear Power Station, 1976-1979 5 Year (X) Month 1979 1978 1977 1976 1976-1979 January 36.75 34.47 31.85
- 34.36 February 30.36 32.88 30.86
- 31.37 March 35.51 34.98 36.36 42.59 37.36 April 39.92 40.67 42.88 49.02 43.12 May 49.56 47.22 50.75 52.58 50.03 June 54.39 50.04 54.21 52.13 52.69 July 55.56 56.03 56.98 58.51 56.77 August 56.73 60.48
- 61.62 59.61 September 53.75 58.59
- 58.94 57.09 October 51.94 52.80
- 54.21 52.98 l
November 48.75 49.22 47.33 45.38 47.67 December 40.86 40.41 39.78 38.18 39.81 I
- Temperatures were incompletely recorded during PNPS outages in these months.
I I I I l l M M M M M M E M M M M - M M Table 8. Monthly Impingement For All Invertebrates Collected From Pilgrim Station Intake Screens, January - December 1979 Species Jan.* Feb. Mar. Apr. May June July Aug. Sept. Oct. Nov. Dec. Totals blue mussel 89 127 344 454** 278** 43I** 834 6 100** 5,300 352 8,315 sand shrimp 25 84 98 2 209 Aurelia auritia 40 9 51 6 106 common starfish 4 16 6 5 2 8 2 2 2 26 24 100 horseshoe crab 6 26 21 2 I I 57 long-fin squid 4 10 8 19 1 42 rock crab 2 7 6 11 1 2 3 32 C J anca capillata _ 30 30 green crab 6 8 4 7 2 1 2 30 Cirripedia spp. 20 4 24 green sea urchin I 6 2 9 clan worm 4 2 2 8 Paguy s longirarpus t 7 8 acorn barnacle 6 1 7 periwinkle 6 1 7
, Metriditum senile 2 4 1 7 g Arbacia punctata 2 4 6 8
Dichelopardalus lep t oce ros 3 3 Idotea balthica 1 2 3 American lobster i 1 2 short-fin squid 2 2 Cerebratulus facteus ! I crats (unidentiffed) I 1 ctenoptiore 1 I llenricia sanguinolenta 1 I mud snail 1 1 My sis stenolepis 1 I Palemonetes spp. 1 I Totals 130 249 470 502 4ll 455 907 71 104 5,331 384 9,014 Collection Time (hrs.) 5.50 8.0 61.50 99.0 86.0 55.75 21.0 15.50 37.50 21.0 12.0 71.50 488.75 Collection Rate (!/hr.) 16.25 4.05 4.75 5.84 7.37 21.67 58.52 1.89 4.95 444.25 5.37 18.44
- Invertebrates not recorded.
** Mussels too numerous for complete count.
I The greatest collections of mussels were influenced by mussel removal opera-I tions of divers in the vicinity of the seawater circulating and service water pump wells. Sand shrimp appeared in greatest numbers from February-April. Two specimens of the commercially important American lobster (Homarus americanus) were captured, one each in July (62 mm carapace length, 52.1 gms) and November (85 mm carapace length, 250.7 gms with major chelaped missing). This equals 36 lobsters / year at 100% operation of Pilgrim Station. Approximately 565.2 pounds of mixed algae species were recorded during impingement sampling or 1.16 pounds /hr. I I I I I I I I I S g
I
- g 5 SECTION 5 CONCLUSIONS g
- 1. The average Pilgrim I collection rate for the period January-December 197', was 3.24 fish / hour.
- 2. At full-load (conservative assumption) yearly operation the estimated maximum January-December impingement rate was 28,280 fishes (1,095 lbs.).
- 3. Thirty-six species of fish were recorded in 494.25 impingement collection hours.
- 4. The major species collected and their relative percentages of the total collectio1s were Atlantic silverside 73.3%; rsinbow smelt 5.4%; window-pane 2.9%: pollock 2.3%; and winter flounder 2.1%.
- 5. Peaks in impingement collections occurred in March and April for Atlantic silverside during which time hourly rates varied from 8.9 to 24.1. This represented the ninth largest fish mortality incident in Pilgrim Station operational history.
- 6. Impingement rate was statistically insignificant (ANOVA, p 0.05) for Atlantic silversides during dark hours as compared to daylight hours, although generally consistently greater during dark hours.
- 7. Tidal, temperature, and puirp operational variables did not significantly influence collection rates.
.g 8. Intake water temperatures, which reflect ambient water temperatures, were , E relatively low in 1979 compared to the four year monthly averages for l l 1976-1979. I I 1 l 1 1
- I
- 9. The hourly collection rate for invertebrate s was 18.44 with blue mussel j representing 92.2%; sand shrimp 2.3%; jellyfish 1.2%; and common starfish i 1.1% of the catch.
i
- 10. Two American lobsters were collected during impingement sampling which equates to 36 lobsters / year impinged.
l l I I I I I I 1 I I 22 -
i i I SECTION 6 I LITERATURE CITED I I l Americal Fisheries Society. 1970. A list of Common and Scientific Names of Fishes From the United States and Canada. Spec. Pub. No. 6: 150 pp. I Anderson, C. O., Jr., D. J. Brown, B. A. Ketschke, E. M. Elliott and P. L. Rule. 1975. The Effects of the Addition of a Fourth Generating Unit at the Salem Harbor Electric Generating Station on the Marine Ecosystem of Salem Harbor. Mass. Div. Mar. Fish., Boston 47 pp. I Maine Yankee Atomic Power Company. 1978. Impingement Studies. M Final Report, Environmental Surveillance and Studies at the Maine Yankee Nuclear Generating Station (1969-1977). Section 3: 40 pp. I Marshall, B. L. 1978. Impingement of Organisms at Pilgrim Nuclear Power Station: A Multi-Year Study (January 1973-December 1977). In Marine Ecology Studies Related to Operation of Pilgrim Station, Final Report, Section IV: 72 pp. Smith, R. I. (Ed.). 1964. Keyes to Marine Invertebrates of the Woods Hole I Region. Marine Biological Laboratory. Woods Hole, Massachusetts. Stupka, R. C. and R. K. Sharma. 1977. Survey of Fish Impingement at Power Plants in the United States Vol. III. Estuaries and Coastal Waters. Argonne National Lab. 310 pp. I I I 3 a 0 k m C Gl1 D**D .wJM@W].19 "Tf _ocJ o gpts'
sm-M 3 50 O m W m C o Gts 1 m .
I 1 1 l !E l l
SUMMARY
REPORT: FISH SPOTTING OVERFLIGHTS '
; IN WESTERN CAPE C0D BAY IN 1979
!I Prepared by: / d Robert D. Anderson . Senior Marine Fisheries Biologist Approved by: '. Dr. F. J. Mogolesko Environmental Sciences Group Leader I I i I Nuclear Engineering Department Boston Edison Company 800 Boylston Street Boston, MA 02199 April 1979 I I I I _ . _
SUMMARY
REPORT: FISH SPOTTING OVERFLIGHTS IN I WESTERN CAPE COD BAY IN 1979 Fish spotting overflights were made north, south and in the vicinity of I Pilgrim Nuclear Power Station (PNPS) during 1979. Five main groupings of fish were noted by the overflight pilots who are trained to spot fish for commercial fishing operations. The five groupings are herring, consisting I primarily of Atlantic herring (Clupea harengus harengus), alewife (Alosa pseudoharengus) and/or blueback herring (Alosa aestivalis); Atlantic mea-haden (Brevoortia tyrannus); pollock (Pollachius virens); Atlantic mackerel g (Scomber scombrus); and baitfish, consisting primarily of any species too g small to identify but most likely being composed of Atlantic silverside (Menidia menidia), rainbow smelt (Osmerus mordax) or the juveniles of other species. Figure 1 shows the general area covered by the PNPS fish overflight pro-gram, although reports of fish concentrat: _ns are received from further ,I north, also. This summary report is meant for general information purposes only, as it is not possible to quantify with reasonable accuracy the data from this qualitative program. Nevertheless, this program is very valu-able and useful in being responsive to NPDES Permit requirements, docu-
- I menting barrier net effectiveness by confirming large quantities of fishes in the Pilgrim area, and alerting BECo. personnel of the potential for a discharge-related fish mortality.
Table I summarizes location, approximate poundage and seasonal information for the five groupings of fishes defined above. Below are some interpre- ~l tive comments based on general trends illustrated by fish observation data 5 for the five predominant fish groups in 1979:
- 1. Herring - This is a mixed species category but probably consists lI mostly of Atlantic herring. These fish were in the Cape Cod Bay area primarily from Fall through early-Spring, tiost frequently north of PNPS. The alewife and blueback herring are more preva-
- lent in the summer and the 5,000 pounds of juvenile herring ob-served on July 5 inside the PNPS intake breakwaters most proba-bly represented these species. The majority of pounds of herring I observed by fish overflights represents Atlantic herring to a large extent as borne out by commercial catch statistics.
- 2. Atlantic Menhaden - This species is of concern at Pilgrim because
,I of past gas bubble disease mortalities in the discharge canal and thermal plume. As can be seen, menhaden occur over the entire Cape Cod Bay region in the millions of pounds from Spring through I Fall. From late-July through early-September thousands of pounds of menhaden were spotted within a few hundred yards of the PNPS discharge canal but none were detected above the barrier net and I no mortalities were noted. The first commercial catch of menhaden north of Cape Cod in 1979 was made in mid-May. Overflight pilots are particularly adept at identifying this species as commercial ventures depend heavily on accurate observations for success. I
- 3. Pollock - These fish were identified during May in the Pilgrim area. They were not as prolific as the herring and Atlantic menhaden, and no serious incidents have occurred involving them at PNPS although the 6,000 pounds spotted in May were within the intake embayment.
- 4. Atlantic Mackerel,- These fish support a valuable commercial fishery and are reported mostly north of PNPS. They occur in relatively large numbers usually during the Summer months, and no incidents involving them have occurred at Pilgrim Station.
They are an offshore species for the most part but have been ob-served schooling in the PNPS intake embayment, although in 1979 only one sighting was made north of PNPS in October.
- 5. Baitfish - This category is a catchall and may include large num-bers of small unidentified fish. Only one questionable sighting E was made in April, just north of Pilgrim Station, in Plymouth 3 Channel. They may represent the offspring of fishes in the above categories as well as Atlantic silversides and rainbow smelt.
I I I E I I I l I 2-1
Figure 1. FISli SURVEILLANCE OVERFLIGilTS (Critical Area) A
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SUMMARY
REPORT: 1978-1979 INSPECTIONS l OF PILGRIM DISCHARGE CANAL AND FISH BARRIER NET , l I l I Prepared by: d+ M I ' Robert D. Anderson Senior Marine Fisheries Biologist Approved by: . . Dr. F. J. Mogolesko l Environmental Sciences Group Leader I I Nuclear Engineering Department Boston Edison Company I 800 Boylston Street Boston, MA 02199 April 1980 I I l
I
SUMMARY
REPORT: 1978-1979 INSPECTIONS OF PILGRIM DISCHARGE CANAL AND FISH BARRIER NET 1 I Pilgrim Station discharge canal dive surveys were initiated in 1976 to de-scribe and document the effectiveness of a barrier net in excluding fishes and any behavioral or physical observations of marine biota inhabiting the l l canal waters. Biweekly dive inspections of the Pilgrim discharge canal and barrier net were performed from May-October 1978 and 1979 in partial fulfillment of the I Boston Edison Company's Marine Ecology NPDES (EPA) Permit Program. The dives were made around the time of high tide to take advantage of low cur-rent velocities ( ~ 2 fps) in the discharge canal. Marine life upstream I and downstream of the barrier net and functioning of the net were observed. Live marine biota observed in the discharge canal included the following:
- 1. Rockweed (Laminaria sp.)
- 2. Green algae (Enteromorpha)
- 3. Sea anemone (Metridium sp.)
- 4. Common starfish (Asterias forbesi)
- 5. Blue mussel (Mytilus edulis)
- 6. Quahog (Mercenaria mercenaria)
- 7. Green crab (Carcinus maenus)
I 8. 9. 10. Rock crabs (Cancer spp.) Horseshoe crab (Limulus polyphemus) Striped mullet (Mugil cephalus)
- 11. American eel (Anguilla rostrata)
- 12. Atlantic silverside (Menidia menidia)
- 13. Striped killifish (Fundulus majalis)
- 14. Alewife (Alosa pseudoharengus)
- 15. Three-spined stickleback (Gasterosteus aculeatu Q
- 16. Bluefish (Pomatomus saltatrix)
- 17. Pollock (Pollachius virens)
- 18. Mummichog (Fundulus heteroclitus)
Observations made of the above species revealed no signs of stress or gas l I bubble disease upon close inspection. No individuals of these species ob-served upstream of the barrier were likely to have entered the canal due to failure of the net. They were either small enough to get through the 2" mesh of the net or came from the intake via the screenwash sluiceway. Species taken by sportfishermen off the ends of the discharge breakwaters were: I I 1. 2. 3. Tautog (Tautoga onitis) Cunner (Tautogolabrus adspersus) Striped bass (Morone saxatilis) I i 4. 5. Bluefish Pollock I I Many of these fish were closely examined onshore and showed no signs of gas I bubble disease. Although large schools of bluefish and other species were apparent in the near-field thermal plume, as evidenced by catches and diving sea gulls, they were not observed upstream of the barrier net. This indi-cated, and close observation of the barrier net confirmed, that the net was operating successfully. Each inspection covered six major regions of the canal around the barrier net (Figure 1). To put major observations made during 1978 and 1979 in g perspective, the following qualitative monthly breakdown is presented which 3 combines dives during both 1978 and 1979. May Algae and rockweed occurred densely over the bottom of the discharge canal upstream of the barrier net. Virtually no live blue mussels were observed in the discharge canal in 1979, unlike 1978 when mats of them coated the canal bottom several inches thick. Mussel predators, crabs and starfish, were noted. Several pairs of green crabs were seen in mating postures. g Evidently a couple of American eels had taken up residence in the discharge g canal, upstream of the footbridge. Atlantic silverside were schooling in front of the barrier net and downstream of it, behind the wings. Some Pol-lock were caught by sportfishermen at the end of the discharge canal in 1979. One Atlantic menhaden was found caught between a net wing and side l sill, having evidently tried to enter the canal in vain. Approximately 2 dozen adult Atlantic silverside which were dead in the cod end of the barrier net showed external gas bubble disease symptoms on April 27, 1979. The barrier net was in relatively good condition. June Green and red algae covered the canal bottom and sides. Mummichogs dis-playing cpawning behavior upstream of the barrier net and silversides were observ; . Catches of small bluefish and striped bass were made at the canal termi as in 1979. The mussels noted in May 1978 thinned out along with their ! asse.iated predators. Horseshoe crabs were feeding directly in front of the l ba -ier net. No signs of gas bubble disease were detected on marine biota and t'.e net was in acceptable condition. July Green algae was abundant upstream of the barrier net. In 1978, the dis-charge canal bottom became completely coated with sea anemones and bluefish were being caught off the jetties. Atlantic silversides were schooling on either side of the barrier net and a few juvenile alewife were mixed in with them. An American eel was noted upstream of the footbridge. All fishes appeared healthy and showed no gas bubble disease symptoms. The l a j barrier net was in relatively good condition. August The canal bottom and sides were coated with tiny sea anemones. Small a groups of Atlantic silverside were noted downstream of the barrier net and large catches of bluefish were made on the weekends. In late August 1978 g I I a fish kill of approximately 2,000 herring occurred next to the discharge canal. Despite large quantities of herring in the plume region as evi-I denced by this kill, at no time during this period were any fishes noted above the barrier net. The barrier net was in poor condition in 1979, but high discharge water temperatures ( ~ 95*F) served to dissuade fish from entering the canal. No gas bubble disease symptoms were noted on marine I life. September The canal was covered by the growth of sea anemones. In spots clumps of mussels were being fed upon by rock crabs. Altantic silversides were swim-I ming downstream of the barrier net and showed no signs of gas bubble dis-ease. Bluefish fed on young Altantic mackerel off the discharge jetties in 1978. Sporadic catches of bluefish were made off the discharge jetties. In 1979 the barrier net was replaced with a new net. October A mixture of sea anemones and algae dominated the bottom of the discharge canal at different times but the former were gone by early November. As the sea anemones disappeared greater numbers of crabs and other invertbrates I were noted in the canal. An American eel was observed in its usual loca-tion just upstream of the footbridge. Striped killifish and mummichogs were noted mostly downstream of the barrier net. In late October schools of juvenile bluefish were seen downstream of the net, and also several large striped mullet under the net in 1979. Maintenance divers had re-ported spotting tautog and striped bass juveniles near the barrier net but the latter were probably mullet. The bluefish and mullet appeared to be I trying to gain access upstream of the net, but in vain as none were noted above it. No external symptoms of gas bubble disease were obvious on any species observed. In 1978 a new barrier net was placed in the discharge I canal. l l i l 1 I 1 I 64 W u . e :2 .. E d o n. s d5 ( '?N _ i gyb , $ !! tine - w%ei p w .s ,, g; warasE_ssw; gh -m -u x., n N. - .
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.i j d l J FINAL REPORT l ON ProRODUCTION AND SPAWNING POPULATION STRUCTURE Oi ANADROM0US RAINBOW SMELT, OSMERUS MORDAX (MITCHILLJ, THE JONES RIVER, MASSACHUSETTS I
; _ Project Report for 1979 by Robert P. Lawton I
I . February 29, 1980 Massachusetts Department of Fisheries, Wildlife and Recreational Vehicles I Division of Marine Fisheries 100 Cambridge Street Boston, Massachusetts 02202 II 11 l
I I TABLE OF CONTENTS I INTRODUCTION 1 2 STUDY AREA 3 METHODS AND MATERIALS 9 RESULTS AND DISCUSSION 23 ACKNOWLEDGEMENTS LITERATURE CITED 24 I 'I 'I 'I I ,.,. I I I - ---- - - - - . . - _ _ _
I LIST OF TABL)' 1 Table I
- 1. Number of smelt by sex and for combined sexes, per-centage of females, and average catch per unit effort (CPUE) in nighttime dip net samples collected from the Jones River spawning area, 1979.
- 2. Catch composition by sex and for combined sexes for each sampling hour (pooled data) over the duration of the run in the Jones River, 1979. l
- 3. Calculated age composition (%) by sex and for com- '
bined sexes of the 1979 rainbow smelt spawning-run, Jones River, Massachusetts.
- 4. Average lengths of mature rainbow smelt, by age and sex, collected immediately prior to and during spawning season from five locations ranging from Massachusetts to Canada.
- 5. Total length (mm) and weight (g) by age-class of male l and female rainbow smelt from the Jones River, 5 Massachusetts, 1979.
- 6. Sampling zones, stations, distance of sampling units (in m and ft) below the Elm St. Dam, and smelt egg densities Per Square Inch (2.5 cm2 ) on sampling units by station and zone during the 1979 smelt spawning-run in the Jones River.
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- 1. Plymouth, Kingston, and Duxbury Bay and tributaries -
one of which is the Jones River.
- 2. A diagrammatic of the Jones River spawning area showing egg sampling zones, sampling stations, zone area, and K constants.
- 3. Daily water temperature (c) ranges and means recorded in the Jones River, 1979.
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I 1 INTRODUCTION I This study was designed to obtain baseline information on aspects of re-1 productive biology, spawning activity, and population structure of anadromous rainbow smelt, Osmerus mordax (Mitchill) from the Jones River in Kingston, Massachusetts. As part of this investigation, smelt were specifically examined l for incidence of Glugea hertwigi, a microsporidian parasite of the digestive j tract and gonads, and piscine erythrocytic necrosis (PEN), an erythrocytic infection of viral etiology. 1 Smelt has been selected as a representative important species (RIS) to I j assess impact of Pilgrim Nuclear Power Station (PNPS) operation on the local fish l population (Stone and Webster 1975). It is assumed that smelt frequenting l the environs of PNPS are essentially from local stock which originates from nearby Plymouth-Kingston-Duxbury Bay (PKDB) complex (Stone and Webster 1975). i l This area supports intensive smelt breeding. Smelt are essentially confined I to the inshore zone usually within a mile of the estuary of origin (Bigelow I and Schroeder 1953), and there are few other known spawning runs in the l vicinity of Plymouth (Reback and DiCarlo 1972). To date, however, docu-mented information on the local population is limited. 1 An estimated impingement mortality of 6,200 smelt occurred at PNPS from l 11 to 29 December, 1978 (Lawton et al. 1979). Impinged smelt were assumed l to be progeny of PKDB,probably natal to the Jones River spawning-run. Iwanowic et al. (1974) indicated that of the tributaries to PKDB utilized for smelt spawning, the Jones River, by far, supports the largest run. In l fact, the Jones River run is one of the largest in the state and has histori-l cally been important. The Massachusetts Division of Marine Fisheries (DMF) has used this river as a source of smelt eggs for transplanting purposes. r u F
It was our assessment that the aforementioned impingement mortality, al-though deemed moderate, could have significant impact on the smelt run and population in the Jones River (Lawton et al. 1979). There were indications that both the 1977 and 1978 year-classes of smelt from this river were de-pressed. Moreover, smelt, sampled in the Jones River in 1977 and at PNPS during the impingement incident, were affected by Glugea and PEN. Signifi-cance of infections and resultant disease symptoms was unknown. Comprehen-sive population data are implicit to assess effects of the operation of PNPS on the local stock. STUDY APIA , PKDB is a coastal embayment (Figure 1), whose morphometry and hydro-graphy were summarized by Iwanowic: et al. (1974). l Four major streams enter the bay: Back, Bluefish, Eel, and Jones Rivers. Headwaters of the Jones River include Silver Lake in Pembroke and swamp lands in Kingston and Plympton. Reback and DiCarlo (1972) reported numerous small confluents, most of which are impounded, augment flow in the Jones River. The main branch he.s two impoundments. The first is a dam located at Elm Street in Kingston. A 15.2 m (50 ft) concrete fishway built by DMF at this site allows the passage of alewives and blueback herring but is impassable to spawning-run smelt. McKenzie (1964) reported that smelt are unable to ascend vertical falls greater than 15.2 to 25.4 cm (6-10 inch). Further up river, there is a second impoundment which has no fishway. Based en qualitative and quantitative observations of reproductive activity in past years, i.e. spatial distribut bn of spawning smelt and egg density deposition, the principal study area (Figure 2) was delimited as the I
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-NM 3,620 m (39,060 ft )
K(B)=5,624,640 Zone B feet 10 11 12 0 385 17 meters l I I 13 14 15 i Zone C ' 3,980 m2 (42,840 ft 2) K(C)=6,168,960 16 17 18 I I Rte 3A Bridge l Figure 2. A diagrammatic of the Jones River spawning area showing egg I sampling ::ones, sampling stations, zone area and K . constants. I
l l Jones River from below the Elm Street Dam iupper limit) to the U.S. Inter-state Rte. 3A bridge (lower limit). Su>plemental egg density data were col-l I lected from the following tributaries: Eel River, Town Broek, and Smelt Brook; all support smelt runs. METHODS AND MATERIALS Field Procedures Physical-chemical river characteristics. Morphometric data were ob-tained from a U.S.G.S. Topographic Map and in situ measurements. Linear and area measurements were made employing a map rotometer and planimeter, and tape measure in the field. Substrate type was qualitatively identified. Measurements of water depth and velocity were recorded on a flood and ebb tide at a location approximately 25 m (82 ft) below the Elm Street Dam employing depth soundings and G.M. flowmeter, respectively. I Air and water temperatures were recorded throughout the field study at the base of the dam employing a FT-3 hydrographic thermometer and constant temperature recorder. Salinity was measured on a spring flood and ebb tide both at the upper and lower bounds of the study area using a YSI, model 33, SCT meter. Dissolved oxygen (DO) and hydrogen ion (pH) concentrations were deter-mined employing the azide modification of the Winkler Technique (Strickland and Parsons 1972) and a pH meter (Corning model 610 A), respectively. Total i gas pressure was measured directly with a Weiss saturemeter (ECO Enterprises, 1. Seattle, WA), and gas saturations calculated by formulae computation after l Fickelsen et al. (1975). A Hach portable water analysis kit was used to f obtain point measurements of detergents, f 1 I _3_ l l
I Reproductive parameters. During the spawning run, adult smelt were collected within the upper 25 m (82 ft) of the study area because of sampling l accessibility. Prior to inception of sampling, day and night observations ' were made to ascertain when fish first occupied the spawning grounds. Samples of smelt were collected approximately every other night from late March when fish arrived until early May when fish emigrated from the river. We employed a 1.44 m2 (16 ft2) dip net of 19 mm (3/4 inch) stretched mesh. This netting retained all sizes of smelt found in the spawning run. The dip net was generally hauled hourly during a sampling night (1900 hrs to 0300 hrs). Supplemental sampling was undertaken, as time allowed, during the daytime utilizing a nylon cast net of 2.1 m (7 ft) diameter and 10 mm (3/8 inch) square mesh. All fish were enumerated, sexed, and measured (total length) to the nearest mm. Sex was determined by examining each fish for the presence of nuptual tubercles (McKenzie 1964). If questionable, the fish was gently squeezed to extrude a small amount of gametes. Those not retained were re-leased at the point of capture to minimize sampling mortality. Fish caught at night were reccrded as catch per unit of fishing effort (CPUE), i.e., catch / lift of the dip net. This allowed us to quantify temporal changes in relative abundance of spawning-run smelt over a sampling night and throughout the run. We assumed the dip net sampled a proportional number of smelt present on the spawning grounds each night. During the entire run, we strived to retain 20 fish per em interval of length by sex throughout the range of sizes. These fish were also measured for fork length and weighed to the nearest 0.1 g. To determine age structure of the spawning stock, scale samples were taken off the left side of these E
fish just below the anterior pcrtion of the dorsal fin. Scales were stored in envelopes for subsequent age determination. Samples of retained fish were f preserved in buffered 10% formalin or frozen for laboratory examination for Glugea. For evidence of PEN, blood samples were collected from live fish. Spawning activity. To document the spatial and temporal parameters of the 1979 spawning run, including the period of spawning and time of hatching, an egg sampling unit was necessary. Spawning smelt broadcast demersal, ad-hesive eggs which attach to stream substrate. To quantify egg production, we utilized a sampling unit designed by DMF to collect eggs for transplanting purposes. Enumeration of eggs collected on unit area sections of the smelt trays placed at permanent locations provided estimates of egg density and pro-duction. A sampling unit consisted of a 35.6 x 45.7 cm (14 x 18 inch) woeden frame (outside dimensions) or 25.4 x 35.6 cm (10 x 14 inch) inside dimensions which had chicken wire for a top and bottom. All trays were filled with sphagnum moss to provide egg depositional surface. Steel bars attached to the frame on the bottom of each tray provided weight to anchor the unit to the substrate in turbulent areas. A sampling site was marked with a steel rod (painted fluorescent red) driven into the stream bottom. For added stability, sampling units were secured by a wire loop to station markers. Each unit was identi-fied by a station number affixed to the frame. M Placement of egg sampling units was based on past DMF observations of egg density distribution. We divided the Jones River spawning grounds into three zones of unequal areas (Figure 2): Zone A, upstream spawning area of l 828 m2 (8,910 ft2); Zone B, midstream spawning area of 3,620 m2 (39,060 ft2); and Zone C, downstream spawning area of 3,980 m2 (42,840 ft2). Eighteen l
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I stations were systematically established, six within each zone. This regimen provided representative but disproportionate sampling. Three sampling units were employed at each station. One unit was desig-nated as the primary surface (A) and remained on station to collect eggs from inception of spawning until just prior to initial hctching. Unit A was then I removed and replaced with a second unit (B), specified as a supplemental sur-face, to ascertain additional deposition. A third unit (C) served as a con-trol and remained on station throughout the period of hatching in order to estimate egg survivorship. It was assumed a pMoM that attachment of eggs to the sampling units was equivalent to that on natural substrate immediately surrounding the units. Rothschild (1961) and Clayton ( 1976) found no significant difference between egg densities on natural bottom and on their sampling units. The validity of our premise was tested during the study by sampling sections of artificial depositional surface and adjacent stream bottom and comparing egg counts. The assumption of parity was cogent when natural substrate was sand or attached macroscopic vegetation but was tenuous with gravel (i.e., stones or pebbles) or rocks. The percent of egg distribution by substrate type was not determined. Replicate 2.5 cm2 (1 inch2 ) sections of depositional surface were sampled and all eggs were carefully removed with fine tweezers from each Unit A, just I prior to initial hatching, and placed in denatured ethyl alcohol for labora-tory enumeration. Hatching was confirmed by the presence of prolarvae which were collected in a 1/2 m (1.6 ft) plankton net secured in the river. Addi-tional egg counts were made from B units. Total egg density per station was considered the sum of the mean of replicate egg counts /2.5 cm2 on Units A and B. E
I Egg survival was to be obtained by first counting 2.5 cm2 sections per I control unit (C) at the termination of hatching. This figure, representing egg mortality, was to be subtracted from total egg density to yield estimates of egg survival / unit surface area. However, by the time hatching was com-pleted, many of the dead eggs had detached from the sampling units negating this method to determine egg survival. Supplemental data. Sampling units were also deployed in Smelt Brook, Town River, and Eel River to determine egg density deposition in these tribu-taries. Total egg production was not determined at these sites. I Laboratory Procedures Data on spawning-run fish were programmed to efficiently handle the large data set. Sex composition of the run was determined. Linear regressions of fork length to total length and total length to weight were calculated using lI ! appropriate programs on the Woods Hole Oceanographic Institute's Xerox Sigma 7 l computer. Length and weight frequency tabulations and plots were made by sex and for pooled catch. Determination of age composition was made from scales utilizing the " shiny line" criterion of McKenzie (1958). A 43X microprojector was employed to facilitate scale readings. Scales were cleaned, mounted between glass slides, 1 and independently read at least twice. If a positive consensus as to age of a particular fish was not obtained or if scales were regenerated and/or unusable, these fish were discarded. Based upon a sample size of 599 fish aged, an age-length key was prepared to determine age composition by sex for spawning-run fish in 1979. 1 A total of 139 fish was examined for Glugea and PEN. Blood smear slides l l
I were fixed in the laboratory in absolute methanol for three minutes. Immedi-ately following fixation, slides were stained for 30 minutes with Giemsa stain, diluted 1:6 with buffered distilled water (pH 7.0) according to Sherburne (1977). This is a permanent stain allowing us to store slides until examination was possible. Subsequently, each slide was scanned for 10 minutes under oil immersion (magnification 970X) in search of PEN lesions in erythrocytes as described by Sherburne (1977) and Sherburne and Bean (1979). Frozen or formalin preserved smelt were retained for necropsy. Just prior to examination, fish were thawed or rinsed in fresh water. A gross examination was performed on the peritoneal cavity for parasites, particularly macroscopic cysts of Glugea hertwigi on the intestinal tract and gonads. Unit area samples of eggs from A and B sampling units for each station were enumerated under magnification employing a binocular dissecting microscope. Estimates of the range, mean, and standard deviation of egg densities were calculated for each of the three ::enes and for pooled data. A study area mean was calculated by weighting each zone mean according to proportional size (area) of the zone relative to the study area. Suspected large vari-ability in egg densities was confirmed; this influenced precision of estimates. A highly skewed egg density distribution was imputed as much to nonuniform egg deposition on stream bottom as to effects of sample size. Consequently, calculations of mean and variance of egg densities resulted in the variance exceeding the mean. Thus, estimates of the mean and variance were limited in precision, and it was not possible to calculate meaningful confidence limits about the mean. Nevertheless, sources and magnitude of bias in .eampling pro-cedures were believed to be minimal. To estimate egg production, we followed methods of representative but I
I disproportional sampling used by Rothschild (1961). Calculations of egg pro-duction within each of the three zones of the study area are the product of the mean egg density on sampling units and a constant value which relates area of each zone to an area count of a single sample surface. Zone estimates were I summed to provide an estimate of total egg production for the 1979 spawning run I in the Jones River. RESULTS AND DISCUSSION Physical-chemical parameters. The Jones River study area included approxi-mately 8,428 m (90,810 ft2) of surface area. In Zone A, there was no differ-ence in water depth and salinity when measured at the time of high and low tide in PKDB, thus indicating a lack of tidal influence. Depth averaged 19 cm (7.5 inch), and salinity was 0.0 /w . By contrast, in Zone C,a tidal influence was evident as a back up of fresh water at high tide. Just above the Rte. 3A bridge, I depth varied from 21 to 150 cm (8.3 to 59.0 inch), however salinity remained at
- 0. 0 o/, at low and high tides, respectively. Water velocities were measured to range from 0.68 m/see to 0.81 m/sec in Zone A. Zone B was a transitional area.
The upper spawning area (Zone A) was characterized by rock, coarse and fine gravel and sand with vegetation interspersed. Zone B was similar in sub-strate composition. In the lower portion of the study area (Zone C), bottom material included fine gravel, substantially more sand, and localized concen-trations of silt. DO concentrations were high, ranging from 11.7 to 12.6 ppm which was ex-pected for this lotic environment during the spring. Readings of pH were slightly alkaline (7.2 - 7.8). Gas levels approximated equilibrium, i.e. 100% saturation. No detergent concentrations were detected when measurements I 3 9_ I
I were taken; however on several occasions in late afternoon, apparent deter-gent discharges which discolored the water were observed to emanate from up-river of the study area. At the time, a manufacturing firm located upstream of the study area was reportedly discharging detergents into the river. Water temperature was first measured on 12 March at 2.5C (37F) when no fish were observed in the study area. On 13 March, water temperatures were 1.0C (34F) below the Elm Street Dam in the morning and increased to 3.5C (38F) by late evening when measured at the latter location and at the Rte. 3A Bridge. An aggregation of smelt was observed that morning in a pool below the bridge. From 14 March through 21 March, no fish were observed day or night above the Rte. 3A bridge. Water temperatures ranged from 2.0 to 6.5C (36-44F) during this period. Continuous temperature recordings were obtained from 15 March through 3 May (Figure 3). Reproductive Parameters Temperature and the spawning run. Smelt first arrived on the spawning grounds on 22 March when water temperature reached 7.0C (45F). Mean water temperature had increased rapidly subsequent to 19 March (Figure 3). McKen::ie (1964) reported that in smaller tributaries to the Miramichi River and Bay in New Brunswick, spawning-run smelt rarely arrived until temperatures were 6-7C (43-45F). Onset of the spawning season in Massachusetts has ranged from late February in southern streams (Crestin 1973) to mid-March in areas farther north (Clayton 1976; and Murawski 1976), occurring when water temperatures reached 4-6C (39-43F). The Massachusetts Division of Fisheries and Game (1921) re-ported that in the Weir River, Hingham and in the Jones River, a temperature ~ of at least 7C (45F) is necessary for anset of the spawning season.
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I Smelt were first collected on 23 March during the daytime with a cast net. Night sampling using a dip net ccamenced on 26 March and continued through 5 May. Subsequent to the latter date, so few smelt were observed in the river, sampling was terminated. Water temperature at the time was about 16C (61F). McKenzie (1964) indicated that late spawners in New Brunswick brooks usually emigrated before temperatures reached 15C (59F), although some spent males were found at temperatures of 19-20C (66-68F). By contrast, Clayton (1976) stated that spawning concluded in the Parker River, Massachusetts in mid-April when water temperature was 8C (46F). Distribution, abundance, and sex compositicn. A total of 13,215 smelt (11,920 males and 1,295 females) was collected during day and night sampling. All the fish captured, except for one, were sexually mature. The number of fish recaptured was not determined as no fish were tagged er marked. Our observations revealed that although there was no evidence of daytime spawning, small numbers of smelt remained on the spawning grounds during the day. Of the 618 fish sampled during daylight hours, males comprised 97.0% of the catch. Exhibiting a diurnal aggregated dispersion pattern while on the spawning grounds, smelt schooled in pools or troughs where water velocity was reduced. Of the 12,597 smelt collected at night, 89.9% were males and 10.1% females (Table 1). Overall sex ratio (pooled nighttime data) was 8.86 males to 1.00 female. The relative representation of females varied from 0.0 to 1 19.1% in nighttime totals over the duration of the run (Table 1). Kendall l (1927), McKenzie (1964, and Murawski (1976) also collected far more males than females on other smelt spawning grounds. From 1949-1953, McKenzie (1964) found 1 1 I that in various New Brunswick smelt spawning brooks, females comprised 31% of i e l
I Table 1. Number of smelt by sex and for combined sexes, I percentage of females, and average catch per unit effort (CPUE) in nighttime dip net samples col-lected from the Jones River spawning area, 1979. l Sampling night No. of Total % x CPUE Date Sets Fish Males Females Females (combined sexes) I March 26 7 87 71 16 18.4 12.4 l 28 8 491 477 14 2.8 61.4 l 30 8 290 280 10 3.4 36.2 I April 1 9 1,004 946 58 5.8 111.6 3 2 2 2 0 0.0 1.0 l l 5 7 35 34 1 2.8 5.0 7 6 27 26 1 3.7 4.5 u 10 7 588 580 8 1.4 84.0 13 7 878 847 31 3.5 125.4 18 9 1,239 1,081 158 12.8 137.7 l 20 9 1,507 1,369 138 9.2 167.4 22 9 3,247 2,915 332 10.2 360.9 25 9 1,348 1,090 258 19.1 149.8 l 27 8 985 863 122 12.4 123.1 29 5 551 479 72 13.1 110.2 L May 5 7 318 260 58 18.2 45.4 Totals 117 12,597 11,320 1,277 10.1 107.7 E
I overnight smelt catches. In close agreement with our findings, Murawski (1976) reported that female smelt comprised 11.08% of pooled nightly catches at the Parker River spawning-run in 1974 and 10.50% in 1975. A predominance of males in smelt spawning runs apparently represents a shift in sex ratio during spawning season. According to Murawski et al. (in press), overall spawning ratios in the Parker River were 8.03 males to 1.00 female in 1974 and 8.56 to 1.00 in 1975. However, they reported that males and females were found in approximately equal numbers in the winter sport fishery of the area. Murawski (1976) purported the discrepancy in sex ratios resulted from the average male remaining on the spawning grounds 4.05 times longer than the average female. Rupp (1968) reported individual males in Branch Lake, Maine, engaged in spawning for up to eight nights as opposed to females whose maximum activity spanned four nights. Our observations indicate that after sunset, smelt on the Jones River spawning grounds dispersed from clumped distributions and initially moved about more or less at random. In corroboration with the work of Rupp (1965), we noted that in the early hours of darkness, pre-spawning fish were percep-tively wary and easily disturbed by a moving light or a commotion in the water. Total numbers of fish on the spawning grounds generally ir. creased through-out the night via new arrivals and maximized at 0300 hrs (Table 2). Whereas the number of males peaked at 0300 hrs (pooled sampling nights' data), the number of females peaked at 0100 hrs. Three to four hours after sunset, the highest proportion of females to males was recorded. Ccemencing at this time, the fish were characterized by a general lack of wariness and minimal trans-location as they could easily be approached employing a steady beam of light. According to Rupp (1965), this behavioral posture signified inception of I
I I Tabte 2. Catch composition by sex and for combined sexes for each samp1ing hour (poo1ed data) over the duration of the run in the Jones River, 1979. 1 I Time, No. of % of tota 1 No. of % of total Tota 1 % of tota 1 catch (hr) females female catch males male catch fish (combined sexes) 1900 54 4.2 903 e.0 957 7.6 2000 32 2.s 387 419 3.3 3 3.4 2100 76 5.9 726 6.4 802 6.4 I 2200 1s7 12.3 ees 7.e 1,043 e.3 2300 144 11.3 981 e.7 1,12s e.9 g 2400 186 14.6 1,353 11.9 1,539 12.2 l g 0100 2s2 20.1 1,eie 1e.1 2,07s 1s.s 0200 223 17.5 2,007 17.7 2,230 17.7 E 0300 148 11.e 2,2s9 20.0 2,407 19.1 l i - Tota 1s 1277 100.0 11,320 100.0 12,597 100.0 1 E 1 I 1 l 1 l L n L P l -
r b . spawning activity which is influenced by some threshold level of intragroup f stimulation involving density of smelt on the run and/or presence of a cer-L tain proportion of females. Although no sampling was conducted after 0300 hrs, we observed that by sunrise (= 0500 hrs) spawning had terminated, and most smelt departed from the spawning grounds. The remaining fish congregated into pools and troughs and oriented themselves facing into the current while maintaining their general position unless disturbed. There-was no evidence of daytime spawning in the Jones River. Clayton et al. (1978) reported there is no evidence of daylight spawning in Massachusetts. CPUE data (Table 1) indicated that the number of spawning fish generally increased the first week of the run but substantially declined the second week concomitant with an overall decline in water temperature (Figure 3). It is noteworthy that strong northeast winds prevailed at that time. During the following week, wind direction changed and both water temperature and CPUE 3 increased. Maximum numbers of spawning fish occurred in the run during the fourth and fifth weeks, with peak CPUE recorded on 22 April. Contrary to our findings, Clayton et al. (1978), summari::ing smelt studies from New Brunswick ( to Massachusetts, reported that maximum numbers of spawning smelt usually occurred about one to two weeks after a run began. It should be noted, however, that the number of smelt in the river on any given night may not necessarily have reflected spawning intensity. Rothschild (1961) found that in Dean Brook, Maine, peak numbers of smelt in the brook did { not parallel peak egg depositions. Age composition. A total of 599 fish were aged. Age / length keys were developed by sex for the 1979 spawning run according to Ketchen (1950). Age [ r .
I distributions were calculated from corresponding keys (Table 3). Five age groups were present in the run. The first three age groups (pooled sexes) comprised 99.2% of the spawning fish. The predominant age class was two-year olds which comprised 64.8% of the run. Age III fish constituted (13.4%) the second largest age group. Warfel et al. (1943) sampled four age I groups in a spawning-run in Great Bay, New Hampshire; no five-year old fish were collected. Their findings were similar to ours, in that two and three-year olds predominated. Murawski et al. (1976) found that in the Parker River, Massachusetts, two-year old smelt predominated in the 194 and 1975 spawning-runs. Age I males and females were less abundant than age II and III cohorts in the Jones River. Apparently one-year olds are not fully recruited to the spawning population. In contrast to the findings of Warfel et al. (1943), Murawski (1976), and this study; McKenzie (1958) and Flagg (1972) collected no one-year old smelt in spawning-runs of the Miramichi River, New Brunswick I and the Kennebec River, Maine, respectively (Table 4). Murawski (1976) proffered that since Parker Ri.*er smelt grew faster than Miramichi River fish, a larger number of the former age I fish would reach a body size necessary for onset of maturation. This is based on the premise that maturity is related more to body size than to age. I Total length-ferklength relationship. It behooved us to relate total length and fork leng*h of smelt measured on the run. Smelt data measurements obtained in prior years via trawling and gill netting in the environs of FNPS were recorded in fork length. Whereas, most smelt studies in the "open" literature, report meas" ements in total length. Thus, a total length-fork I length (TL-FL) relationship was determined by linear regression (untransformed I;
L [ Table 3. Calculated age composition (%) by sex and for combined sexes of the 1979 rainbow smelt spawning run, Jones River, Massachusetts. r L 7 Pooled L Year Class Age Male Female Sexes 1978 I 15.0 15.1 15.0 l L 1977 II 64.6 66.7 64.8 1976 III 19.7 16.7 19.4 1975 IV 0.7 1.0 0.7 1974 V <0.1 0.5 0.1 [ Total 100.0 100.0 100.0 Number Aged 364 + 235 = 599 Number Measured 11,803 + 1,290 = 13,093 [ [ [ [ [ [ 4 . .
I I Table 4 Average lengths of mature rainbow smelt, by age and sex, collected immediately prior to and during spawning season from five locations g ranging from Massachusetts to Canada. 5 Total length at capture (mm) Location Investigator Sex 1 2 m3 4 5 Great Bay, Warfel et al. MSF 86 150 171 220 - New Hampshire (1943) - - Miramichi River, McKen::le
- M -
157 178 196 211 New Brunswick (1958) F - 162 186 212 238 hennebec Plver, Maine Flagg (1972) M&F - 169 191 210 232 I Parker River, Murawski M 141 188 208 236 242 Massachusetts (1976) F 140 197 219 245 249 Jones River, Present Study M 136 192 207 230 242 Massachusetts (1980) F 136 196 214 251 253 I
- Measurements converted by Murawski (1976) from standard to total length.
I I' I I I l l I
I data) of total length on fork length for 620 smelt (pocied sexes) collected in the Jones River. This relationship is expressed as: FL =-4.5176851 + 0.9261072 (TL) (r = 0.99655) . l Lenzth and weight. Linear regressions (log 10/10810 transformation) of total length on weight were calculated. The stochastic model employed to re-late these variables for individual fish is: log 10W = log a + b(log 10L ) (#) where W = weight in g, a and b = constants, and L = total length in mm. A correlation coefficient (r) was calculated for each equation. Data were analyzed by sex and also combined to generate the following equations: Males log 10W =-5.595846 + 3.146908(log 10L ) (r = 0.99007) Females log 10W =-5.844075 + 3.269434(logioL) (r = 0.98937) Pooled sexes log 10W =-5.714457 + 3.204401(log 10L ) (r = 0.98852). Murawski (1978) reported the following length-weight relationship for smelt from the Parker Pdver: log 10W :-6.0315 + 3.3592 log 10L (r = 0.980). The relationship between length and weight of 599 smelt collected from the Jones River is shown in Table 5. The average weight of females generally exceeded that of males at a given length, m Weight and age. Smelt weights by year class for each sex are found in l Table 5. There is a large overlap in weights between age groups. Average weight of females exceeded that of males for all year classes. Males ranged in weight from 7.4 - 94.0 g, and females ranged from 8.7 - 150.3 g. Spawning-I run smelt from the Jones River were substantially heavier than smelt studied in Great Bay, New Hampshire by Warfel et al. (1943) and those reported by Stone l and Webster (1977). According to Warfel et al. (1943) and Stone and Webster I L F' 5 e
I I Table S. Total length (mm) and weight (g) by age class of male and female rainbcw smelt from the Jones River, Massachusetts, 1979. MALES Length at Capture Weight at Capture ! Age No. of Standard Standard Group Fish Mean Deviation Range Mean Deviation Range I 100 136.3 12.0 113-169 13.3 3.5 7.4-24.4 II 182 192.1 20.2 132-238 40.7 13.2 12.7-77.4 j u III 67 206.9 19.7 150-249 51.1 15.8 22.2-94.0 IV 14 230.1 8.8 205-244 69.9 9.4 43.5-80.5 V 1 242.0 - 242 74.5 - 74.5 I FEMALES I 66 135.7 10.3 118.169 13.6 3.9 8.7- 29.1 II 116 196.3 22.1 131-236 46.6 16.4 11.8- 83.2 III 40 214.5 23.5 154-258 63.6 22.9 28.4-125.8 IV 9 251.1 12.4 236-270 108.2 22.4 79.4-150.3 E v 4 253.0 10.0 240-264 u3.2 26.8 77.6-140.8 I 1 I l i I f I I l I
I (1977), respectively, one-year fish hveraged 2.45 and 8 g; two-year fish,16.73 and 14 g; three-year fish, 30.62 and 17 g; four-year fish, 55.00 and 22 g; and five-year fish, none captured and 32 g. Length and age. Length measurements of age groups by sex are found in Tables 4 and 5. There is a considerable range in size within each age-group and overlap between year-classes. The overall length of the total spawning population ranged frem 113-270 mm TL. Males ranged from 113-249 mm TL, and I females, 118-270 mm TL. Calculated mean total lengths indicated that growth is greatest during the first year. Pish (pooled sexes) averaged 58 mm in growth the second year, 17 mm the third year, 30 mm the fourth year, and 7 mm the fifth year. Similar findings were reported by Warfel et al. (1943) for spawning-run smelt in Great Bay, New Hampshire. Jones River males were slightly longer than females at age I, but thereafter, females were longer than males at all ages (Table 4). This agrees with the findings of Murawski and Cole (1978) in the Parker River. Mean lengths by year-class obtained from this study agreed remarkably well with data from the Parker River spawning run; whereas, populations of north-ern contingents exhibit slower growth rates, in that these fish are substantially smaller for each age group (Table 4). Smelt from southern contingents partially recruit to spawning grounds as one-year olds. Parasites. Of the 139 smelt examined for Glugea and PEN, 22% were females. This sample size included representatives from age-groups I through V; all fish were mature. There appeared to be no significant difference in the incidence of either parasite with sex. There was no apparent relation between Glugea and PEN infections in individuals. Of the 135 smelt with PEN, only 20 (14.8%) similarly had Glugea. j l I
I Glugea hertwigi I Overall, 16.5% (23/139) of the fish vere affected by Glugea. Incidence of infection ranged from 0.0% in age I and V fish to 20.6% in age III fish. Sherburne and Bean (1979) examined 100 smelt collected from the Jones River in 1977 and found that 28% were infected with Glugea. Examination of representa-tive samples of smelt collected from an abnormal impingement mortality at PNPS in December, 1978, revealed that 8.3% were infected with Glugea; 5/11 with heavy infections (Lawton et al. 1979). Primary infections in the spawning stock were localized as white, spheri-cal cysts along the intestinal tract. The secondary site of infection was the gonads. Degree of infection varied frem a few cysts to a condition where the abdominal cavity was conspicuously filled with cysts. However, overall, in-tensity of individual infection was relatively light. The significance of Glugea infections and resultant disease symptoms (microsporidosis) on the Jones River smelt stock is unknown. Haley (1957) provided evidence which implicates this parasite in the decline of the smelt fishery in the Atlantic. Nepszy et al. (1978) reported mortality of juvenile
.elt in the Great Lakes resulting from Glugea infestation. Che.. and Power (1972) reported that aside from possibly causing debilitation and death in smelt, the import of Glugea infection is in its' effect on smelt fecundity.
Parasitic cysts have been observed to replace ovarian tissue, thus effecting a substantial reduction in egg production. I Piscine erythrocytic necrosis (PEN) Of the spawning-run smelt examined from the Jones River in 1979, 97.1% - l 1 (135/139) were infected with PEN. All ages were affected, with the lowest I 1 g l I l
I incidence (96.3%) occurring in age II fish. Although none of the one-year fish examined (0/18) were parasitized by Glugea , 100% were infected with PEN. Individual infections were light, however. A majority of the fish with PEN had nuclear lesions in < 1.0% of their erythrocytes. The highest individ-ual infection was 4.7%. Sherburne and Bean (1979) surveyed the incidence and distribution of PEN and Glugea in smelt from Massachusetts to the Canadian Maritimes from 1976-1977. They reported that of the 15 coastal streams sampled, the highest incidences of PEN occurred in the Jones River (100/100) and in the Harringto'n River in Addison, Maine,(100/100); and the highest individual in-fection was 8% in a smelt from the Jones River. The significance of PEN infections on smelt is unknown. Evelyn and Traxler (1978) reported that with two species of talmonids, individuals in-fected with PEN exhibited symptoms of anemia. It is possible that smelt could be weakened or debilitated by severe infections of PEN. I Spawning Activity Spatial and temporal parameters. Spawning commenced in the Jones River the night of 22 March at a water temperature of 7.0C (45F), as evidenced by initial egg deposition on the river bottom observed the next morning. Spawning activity continued until 28 April when water temperature was about 15C (59F). Thus, smelt spawned over a prolonged period of time in the Jones River. Clayton (1976) found that in 1975, spawning commenced in the Parker River on 17 March and concluded on 27 April. Hatching of prolarvae initiated on 23 April, 32 days following commence-ment of spawning and terminated by 15 May. The period of actual egg hatching I lasted 22 days. McKenzie (1964) reported that smelt eggs hatched in 29 days . Il
r at water temperatures of 6-7C (43-45F); 25 days at 7.1-8C (45-46F); and 19 days at 9 to 10C (48-50F). Clayton (1976) reported that in 1975, prolarval ^ hatching in the Parker River began 16 April, which was 31 days after spawning [ commenced, and concluded 7 May. Egg deposition occurred throughout the study area but at varying densities. A light set of eggs was also observed for approximately 91.4 m (100 yd) below the Rte. 3A Bridge but was not quantified in this study. Distribution of eggs was nonuniform throughout the spawning grounds. We did not specifically ana- { lyze for site selection in spawning. However, it was very apparent that the Elm Street Dam, which is impassable to smelt, disproportionately concentrated spawners below it,resulting in an overcrowding of deposited eggs. Rupp (1965) reported on absence of smelt spawning site selectivity in Branch Lake, Maine. 1 Clayton (1976) observed that in the Parker River, site selectivity appeared to l be influenced by only water velocity and not by substrate type or water depth. Mortality. Although our attempts to quantify egg survival failed, we do know that a large mortality of eggs occurred in Zone A of the study area due to crowding. Crowded eggs were subjected to reduced circulation of water and E increased infestation by an unidentified species of fungus which developed { among the many layers of egg masses forming large mats. McKen:le (1964) re-ported the latter situation is typical for spawning areas below obstructions. Visual inspection of eggs within all three zones of the study area revealed substantially more dead eggs in Zone A. Egg production was probably also limited by predation of fish and aquatic { insects, eggs dislodging and washing from the river, the possibility of non-fertilization, and mortality from detergent discharges into the river. Sur-vival was notably higher throughout the study area where eggs were attached to l E [ _ - - - - -
endemic macroscopic river plants and rocks as opposed to those deposited on l' l I sand or silt. Egg density and production. Egg production is considered as the number of eggs deposited on the spawning ground by the spawning population of smelt. To estimate egg production, we first obtained samples of egg densities through-out the study area (Table 6). Zones differed in the densities of smelt eggs found within them. Zone A was the location of greatest egg deposition as a result of the dam blocking further upstream covement of smelt. Mean densities generally decreased with increased distance away from the Elm Street Dam. Station densities ranged from 9 to 2,364 eggs /2.5 cm2 (inch2 ). Average egg densities within Zones A, B, and C were: 1,433.83, 342.67, and 152.00 2 eggs /2.5 cm2 (inch ), respectively. An overall weighted mean density for the 2 study area was 359.78 eggs /2.5 cm2 (inch ) or $1,808.32 eggs /0.3 m2 (ft2), J. DiCarlo (pers. comm.)1 estimated that in previous years, the density of smelt eggs in the Jones River was as high as 230,400 eggs /ft 2 - EEE densities , in Smelt 3 rook, Eel River and Town Brook averaged 347.5, 26.00, and 0 eggs / 2.5 cm2 (inch2 ). Total egg production in these tributaries was not determined. l Trom the literature, it is evident that egg density is directly related to egg survival. McKenzie (1964) observed that the percentage of eggs which hatched ranged from 3.6% at a low egg density of 487 eggs /ft2 to only 0.03% I,' at a very high egg density of 180,000 eggs /ft 2 . He further reported that there were 416 eggs / inch 2 when the eggs just touched each other and were only i one layer thick. Our work substantiated his findings. When densities ex-ceeded the latter value, eggs were generally found to be in layers,with eggs attached on top of earlier spawn. This obviously adversely affected egg sur-l I J. DiCarlo, Marine Fisheries Biologist, Mass. Division of Marine Fisheries, Il Shawme-Crowell Forest, Sandwich, MA 02563 , I
I L Table 6. Sampling zones, stations, distance of sampling units (in m and ft) below the Elm St. Dam, and smelt egg r densities Per Square Inch (2.5 cm2) on sampling L units by station and zone during the 1979 smelt spawning-run in the Jones River. c Mean Density (#/ inch2 ) , F 2 Below Dam Density (#/ inch ) of of Eggs Per Zone { L Zone Station (ft) (m) Eggs Per Station (E) (Std. Dev.) l A 1 84 25.6 2364 2 84 25.6 1159 3 84 25.6 1612 4 171 52.1 973 5 171 52.1 1077 6 171 52.1 1418 1,433.83 512.33 B 7 675 205.7 752 8 675 205.7 799 9 675 205.7 49 10 1095 333.8 83 11 1095 333.8 364 12 1095 333.8 9 342.67 358.12 C 13 2019 615.4 16 14 2019 615.4 31 15 2019 615.4 435 16 2439 743.4 286 17 2439 743.4 11 { 18 2439 743.4 133 152.00 174.03 E E E E .
e L vival to hatching. r Rothschild (1961) and McKenzie (1964) found that maximum prolarval pro-L duction per unit area was obtained at egg densities of 6,000 to 15,000 eggs / [ ft 2 (42 to 104 eggs / inch2 ), which yielded hatching successes of about 1.8 and 2 0.8%, respectively. Rothschild (1961) reported that 80 eggs / inch or 11,475 egg /ft2was optimum egg density for maximum prolarval production. McKenzie { (1964) was in agreement in that he reported 83 eggs / inch2 or 12,000 eggs /ft 2 { as the optimum density. Densities exceeding the aforementioned levels pro- ' duce a lower percentage hatch and fewer larvae /ft2, Accordingly,'none of the sites sampled in Zone A of our study area in E 1979 contained optimum egg densities. At the mean density found for Zone A { (Table 6),McKenzie (1964) reported that egg survivorship would be approximately 0.03% of total egg production for that area of the river. Percentage of hatching should have been better in Zones 3 and C where egg concentrations were sub-stantially reduced. Based on mean egg densities calculated for these areas of the river, and according to McKenzie (1964), egg survivorship probably approached { 0.06% in Zone B and 0.3% in Zone C. To estimate egg production, we first calculated a K constant for each E sampling zone (Figure 2), which related the area of each zone to the unit area enumerated on a single sampling surface. Calculations for estimating zone egg productions equalled the product of the mean egg density on sampling units and the K constant for each zone. Zone estimates were summed and provided an esti-mate of total egg production of 4,706,812,800 (4.7 x 10 9 ) smelt eggs for the 1979 spawning-run in.the Jones River. Via predictive modeling, Stone and Webster (1977) estimated smelt egg production in the Jones River per annum at { 2 x 109 (initial number) and 7.355 x 109 (equilibrium number). Although our esti-mate lies half way between these values, both estimates are of the same magnitude 9 of power, i.e. 10 1 F
I l Applying egg density survivorship values obtained by McKenzie (1964) to our study findings, we estimated that of a total egg production in the Jones River in 1979 of 4.7 x 10 9, 4. 5 x 106 eggs would have survived to hatching, i 1.e., 5.5 x 105 in Zone A, 1.2 x 106 in Zone B, and 2.8 x 106 in Zone C. I During the 1980 spawning run, we will determine site-specific estimates of egg survivorship (percent) within each zone of the spawning grounds. I I I I I I I I I 4 I I 3 I
I ACKNOWLEDGEMENTS ! I I extend much appreciation to numerous staff members of DMF who success-fully conducted various phases of this study. H. Russell Iwancwicz, Doris l Jimenez, and Joseph Pelezarski completed smelt ageing and parasite examinations. Cathy Chabot, Anne O'Hara, and Steve Correia enumerated egg samples and were involved in parasite analysis. Data were programmed by Christine Sheehan, Elizabeth Kouloheras, and James Buckley. Mr. Buckley also served as pro-gramming consultant. James Kennedy of the Massachusetts Division of Fisheries and Wildlife collected temperature data. Thomas Currier coordinated field activities. Field data were collected by Mr. Currier, Sandra Beaton, Elizabeth Amaral, Mando Borgatti, Phillips Brady, Jay Wennemer, Frank Germano, Mark Galkowski, Andrew Kolek and Bruce Estrella. Finished tables and figures were prepared by Susan Faria and Lawrence Furrer. The manuscript was typed by Elear.or Bois. I also extend thanks to Joseph DiCarlo (DMF) and the Pilgrim Adnnistrative-Technical Committee for input into the formulation of this study and to Robert Anderson, of BECo, for his continued support and helpful suggestions. Finally, I thank W. Leigh Bridges, of DMF, for guiding the study and reviewing the manuscript. l 1 l r
I LITERATURE CITE: Bigelow, H.B. and W.C. Schroeder. 1953. Fishes of the Gulf of Maine. U.S. Fish Wildl. Serv. , Fish. Bull. (74): 577p. Chen, M. and G. Power. 1972. Infection of American smelt in Lake Ontario and Lake Erie with the microsporidian parasite Glugea hertwigi. Can. J. 2. col. 50: 1183-1188. Clayton, G.R. 1976. Reproduction, first year growth and distribution of anadromous rainbow smelt, Osmerus mordax (Mitchill), in the Parker g River-Plum Island Sound estuary, Mass. M.S. Thesis. Univ. of Mass., 5 Amherst. 105p.
, C.F. Cole, S.A. Murawski and J. Parrish. 1978. Common Marine Fishes of Coastal Massachusetts. Mass. Cooperative Fishery Research Unit.
231p. Crestin, D.S. 1973. Some aspects of the biology of adults and early life stages of the rainbow smelt, Osmerus mordax (Mitchill), from the Weweantic River estuary, Wareham-Marion, Mass., 1968. M.S. Thesis. E Univ. of Mass. , Amherst. 108p. 5 Evelyn, T.P. and G.S. Traxler. 1978. Viral erythrocytic necrosis: natural g occurrence in Pacific salmon and experimental transmission. J. Fish, g Res. Bd. Can. 35: 903-907. Fickeisen, D.H. , M.J. Schneider, and J.C. Montgomery. 1975. A comparative evaluation of the Weiss saturometer. Trans. Am. Fish. Soc. 104(4): 816-820. Flagg, L.N. 1972. The anadromous smelt fishery of Maine. Maine Dept. Seashore Fish. Res. Bull. (33): 6p. Haley, A.J. 1957. Microsporidian parasite, Glugea hertwigi in American smelt from Great Bay region, New Hampshire. Trans. Am. Fish. Soc. 83: 84-90. Iwanowicz, H.R. , R.D. Anderson, and B. A. Ketschke. 1974. A study of the marine resources of Plymouth, Kingston, and Duxbury Bay. Mono. Ser. No. 17. Mass. Div. Mar. Fish. 37p. Kendall, W.C. 1927. The smelts. Bull. U.S. Bur. Fish. 42: 217-375. Ketchen, K.S. 1950. Stratified subsampling for determining age distribu-tions. Trans. Am. Fish. Soc. 79: 205-212. Lawton, R.P., E. Kouloheras, J. Wennemer, and M. Borgatti. 1979. Progress report on studies to evaluave possible effects of the Pilgrim Nuclear Power Station on the marine environment, July-December,1978. In: g Marine Ecology Studies Related to Operation of Pilgrim Station, Semi- 5 Annual Report No. 13. Boston i'dison Company, Boston, Mass. I
e LTTEP>sTURE CITED (Cont.) > Massachusetts Division of Fisheries and Game. 1921. Smelt. In Annual Report of the Division of Fisheries and Game, Commonwealth of F Massachusetts. pp 75-76. [ McKenzie, R.A. 1958. Age and growth of smelt, Osmerus mordax (Mitchill), " of the Miramichi River, New Brunswick. J. Fish. Res. Bd. Can. 15(6): 1313-1327. F L , 1964. Smelt life history and fishery in the Miramichi River, New Brunswick. Bull. Fish. Res. Bd. Can. 144: 77p. r l Murawski, S.A. 1976. Population dynamics and movement patterns of spawning anadromous rainbow smelt, Osmerus mordax (Mitchill), in the Parker River, Massachusetts. M.S. Thesis. Univ. of Mass., Amherst. 125p. and C.F. Cole. 1978. Population dynamics of anadromous rainbow smelt (Osmerus mordax) in a Massachusetts' river system. Trans. Am. Fish. l Soc. 107(4): 535-542.
, G.R. Clayton, R.J. Reed, and C.F. Cole. (in press). Estuaries.
Dec. 1980. Nepszy, S.J., J. Budd, and A.O. Dechtiar. 1978. Mortality of young-of-the-year rainbow smelt in Lake Erie associated with the occurrence of Glugea hertwigi, J. Wild 1. Dis. 14(2): 233-239. Reback, K.E. and J.S. DiCarlo. 1972. Final completion report. Anadromous l fish project. Mass. Div. Mar. Fish. 113p. (Unpublished). Rothschild, B.J. 1961. Production and survival of eggs of the American I smelt, Osmerus mordax (Mitchill), in Maine. Trans. Amer. Fish. Soc. 90(1): 42-48. I l Rupp, R.S. 1965. Shore-spawning and survival of eggs of the American smelt. I Trans. Amer. Fish. Soc. 94(2): 160-168.
. 1968. Life history and ecology of the smelt (Osmerus mordax) in the f inland waters of Maine. Final Rep., Fed. Aid. Fish. Proj. F-10-R, Maine Dept. Inland Fish Game. 36p.
j Sherburne, S.W. 1977. Occurrence of piscine erythrocytic necrosis (PEN) in the blood of the anadromous alewife, Alosa pseudoharengus, from Maine coastal streams. J. Fish. Res. Bd. Can. 34: 281-286. and L.L. Bean. 1979. Incidence and distribution of piscine erythro-I l i cytic necrosis (PEN) and the microsporidian (Glugea hertwigi) in rain-bow smelt (Osmerus mordax) from Massachusetts to the Canadian Maritimes. Fish. Bull. 77(2): 503-509. I 1 l l _
O l' LITERATURt CITED (Cont. ) Stone and Webster Engineering Corporation. 1975. 316 Demonstration for I Pilgrim Nuclear Power Station: Units 1 and 2. Boston, MA.
. 1977. Supplemental assessment in support of the 316 demonstration, Pilgrim Nuclear Power Station, Units 1 and 2. Boston, MA.
Strickland, J.D.H. and T.R. Parsons. 1972. A practical handbook of seawater analysis. Bulletin 167. Fish. Res. Bd. Canada. 310p. Warfel, H.E., T.P. Trost, and W. H. Jones. 1943. The smelt, Osmerus mordax, in Great Bay, New Hampshire. Trans. Amer. Fish. Soc. 72: 257-262. I I I I. I I I I l I I I-I
5
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h E l hu - Tile ENd
l l MEMOPANDUM I l TO: Members of the Administrative - Technical Committee, Pilgrim Power Plant Investigations l FROM: Christine Sheehan, Marine Fisherie:: Biologist L
SUBJECT:
Minutes of the forty-fourth meeting of the Administrative - . Technical Committee, September 12, 1979 { E DATE: November 5, 1979 The 44th Administrative - Technical Committee meeting was called to orde ,at 10:05 AM in the Boston Edison Company (BECo) offices by chairman Bridges. E Ms. Christine Sheehan, Division of Marine Fisheries (DMT) was I introduced ani assumed the duties of Recording Secretary. Seven agenda items were addressed: I. No corrections to the 43rd Committee minutes were proferred. , II. Semi-annual report Mr. Robert Anderson of BECo informed the committee that due { dates for semi-annual reports are extended to 31 October and 30 April. Mr. Robert Lawton of DMT presented results of data compiled p from 1 January through 30 June 1979. Data from each major study was discussed L and related to past findings. a) Iobster Pot Catch. A total of 787 pots containing 234 legal [ lobsters was sampled. Mean catch rate for May and June (corbined) equaled 0.3 lobsters per pot haul. Quadrat I-ll mean catch rate was 0.7 lobsters per pot haul - 2.3 times higher than the overall study average for this period. b) Irish Moss Landings. Mean harvest rate in area I (Manomet Point) decreased 7.9% but increased 21.0% in area 5 (Pilgrim site). However, { rates for both areas were similar. No adverse PNPS impact was apparent except in the immediate vicinity of the discharge flume. c) Ground Fish Stock Assessment. Two control (reference) E stations (White Horse Beach and Rocky Point) were added to the study area in January. These stations will provide additional references for comparison to the surveillance station. Winter flounder, skate spp., yellowtail [ ocean pout, windowpane and longhorn sculpin were numerically dominant. catch per tow increased from 1978 levels a,s follows: winter flounder - 10.8 flounder, Mean to 19.5, skate - 3.4 to 14.0, windowpane - 1.6 to 3.8, and longhorn sculpin - { 1.1 to 3.0. d) Gill Net. Eight sets of the net produced a total of 1,093 fish representing 21 species. Two new species (weakfish and American plaice) were captured. Cunner, pollock, alewife, and Atlantic herring were numerically abundant. Mean catch per net haul (species combined) declined from last year. F - - - - - - - - - - -
e) Finfish Observational Dives. Dives in the vicinity of the discharge began 24 April. On this date, two lethargic winter flounder (-300 mm TL) were observed at the mouth of the canal. They were suffering from possible thermal stress at a bottom temperature of 22C. During four observational dives, the following species were observed; longhorn sculpin, lobster, winter flounder, pollock, cunner, lumpfish, yellowtail and tautog. g These species exhibited no abnormal behavior with the exception of the g aforementioned flounder and a lethargic tautog and dead cunner noted 10 September. The cunner was believed to have come from a screen wash. None g of the fish exhibited external signs of gas bubble disease. g Robert Anderson noted that there were no alewife morta11 ties this year at PNPS, in the past this usually occurred in August. Leigh Bridges asked if the observational dives were standardized and as such, were we able to determine if the stressed fish observed last year and this year were from the same area. Robert Lawton explained that a systematic approach is followed. All stations are marked, and observations are made at these locations during each dive. He added that the stressed fish were observed at the same location. Leigh also queried about velocity measurements, temperatures, etc. g in the thermal effluent. g Bob Lawton remarked that temperature and dissolved oxygen are measured, but velocities are not. However, velocities are known to range between 2-6 ft/sec (Robert Anderson). f) Dissolved gas. Dissolved gas measurements were reduced to g weekly sampling in the spring and fall. In the intake, total gas and nitrogen g saturations were generally at equilibrium (100%) and monthly oxygen saturations averaged less than 110%. However, during a backwash procedure on 3 May, 1979, saturations in the intake exceeded those in the discharge. The water temperature increased from 16 to 23 C in less than one hour. Oxygen saturation was 150% (the highest value measured in the intake to date). Four dead cunner were observed, probably a result of the sudden increase in temperature. Discharge total gas and oxygen saturations were highest in April, with monthly means of 127 and 136% respectively. Nitrogen saturation was highest in March with a monthly mean of 119%. No incidence of gas bubble disease was observed during this period. g) Smelt. Robert Anderson noted that from 12-29 December 1978 an impingement mortality of approximately 6,000 smelt occurred at PNPS. A subcommittee was formed to investigate the need for studying the local smelt population whose major source was felt to be the Jones River. A study program was initiated in March as a result of subcommittee recommendations. Robert Lawton prepared a proposal with the objective of gathering baseline information in 1979 on the reproductive biology, spawning activity, population structure and parasitic infestation of smelt in the Jones River. Spawning run fish were collected, enumerated, sexed
i - measured, weighed, and scales taken for aging. Blood samples were taken from ~150 fish for parasitic analysis (PEN and Glugea hertwigi). Of the approximate 10,000 fish sampled at night only one was im-mature. A total of 8,374 males and 947 females were collected for a ratio of 8.84 males to 1.00 female. It has been hypothesized that this is due to males remaining on the spawning grounds longer. The age percent frequencies for both males and females were similar; Females Males Age 1 28% 27% 2 49% 50% 3 17% 18% 4 4% 4% 5 2% 0.3% It was found that the mean total length for one year old males was slightly longer than for one year old females. However females are longer than males at all other ages. Clint Watson informed the Committee that the discharge of detergent pollutants from Barnes Worsted, Inc. on the Jones River had ceased. This company recently went out of business. They were under orders from the Attorney I General's office to install proper treatment equipment. Mr. Watson further commented on another discharge problem (cyanide and heavy metals) from a nail company on nearby Smelt Brook. The brook passes under the building; and in the past substantial smelt kills have occurred. III. Progress Report - Editorial Subcommittee. Leigh Bridges reported that this -subcommittee has agreed to pursue grat monies to fund publication of the final report. Coastal Zone Management u s contacted about coastal energy impact monies, which will be I available for anergy facilities of any kind. If a grant cannot be other avenues for funding the publication are limited. The intent obatined of the subcommittee is to publish through the American Fisheries Society Transactions. IV. Sluiceway Update. Robert Anderson presented plans for the temporary sluiceway requested by the Environmental Protection Agency and Mass. Division of Water Pollution Control. The intak,e screens are to be cleaned by a double spray wash system. The first wash is a gentle 10-20 PSI of pressure followed by an 80-100 PSI wash. Impinged fish and debris will fall into a four to six inch deep sluiceway trough made of corrugated sheet metal to reduce water velocities. The trough will be covered by a screen to preclude predators and will egress into the intake embayment via,a drop of approximately fifteen feet. Other power plants demonstrate similar drops with no mortalities. An alternate system will remain in use to stunt large quantities I of debris into the discharge during storms. Al Eipper asked if there is a higher impingement rate during n~ortheast (NE) storms. Robert Lawton replied that there is no demonstrated correlation between high impingement and NE storms. Impingement appears related to seasonality of species occurrence I
Wayne Davis and Leigh Bridges asked how often there is a screen wash and if screen washes are triggered by a pressure differential. Robert Anderson re-plied that the screens are not pressure sensitive but are " tripped" manually every eight hours and remain on for 20-30 minutes. Leigh Bridges suggested that bucket-type screens should be investigated for Unit II because they are very effective (open literature reports approximately 90% survival). V. Other Business. Two topics were addressed: a) Leigh expressed pleasure at acquiring benthic biologists on the Committee and hoped that ecological studies conducted at PNPS would be benefited by Don Miller's and Wayne Davis' direction. Don Miller asked that a subcommittee be formed to review benthic studies. The following members were appointed: Don Miller (subcommittee chairman) - EPA Wayne Davis - EPA Robert Lawton - DMF Lew Scotten - BECo l Robert Leger - EPA E b) Leigh Bridges explained that Lew Scotton had contacted him requesting that he be allowed to analyze entrainment data to be collected next year by a private consulting group - probably Marine Research, Inc. The Com-mittee discussed the problems of the credibility of a company biologist anal-yzing and reporting data, differences in biological interpretation, and the separation of data collection and analysis. Lew Scotton explained that entrainment sampling was in a monitoring mode and with his own background in ichthyoplankton, he was qualified and would gain personal satisfaction to conduct the analysis and report writing phases of this program. He also added the company could reduce costs. Leigh Bridges felt in this particular case, the request was res-onable because of the circumstances and further the committee reviews all g reports and appraises their adequacy. However, he believed that the issue g of future company involvement in data interpretation and report writing should be decided on a case by case basis. Most members agreed with this logic. Robert Lawton motioned that Lew Scotton be allowed to assume analysis of entrainment data to be tentatively collected by Marine Research, Inc in 1980. The motion was second and passed via committee vote. VI. Subsequent Report and Review of Marine Fisheries Resource g Studies at Pilgrim Station. El Dr. Charles Cole referred to his letter of 1 August 1979 listing l the subcommittee recommendations: . l
- 1. Lobster Investigations. That this study continue at the j same level and effort for at least another year.
- 2. Irish Moss Investigation. That this study continue at the same level and effort. Recommend that three-year and one-year contracts be considered and that the best alternative be chosen by the two parties involved.
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- 3. Dissolved Gas Program. That this program be continued but only in spring and fall. This also should be a multiyear contract if agreed to by both participants.
I 4 Finfish Investigations.
- a. Fish kill investigations: DMT already has statutory obligations in this area, and no funds recommended.
- b. Finfish Eservations: That this program began in 1978 be continued for at least another year to build experience.
- c. Trawl study: That the modifications made in 1978 to the trawl study be continued for another year.
I d. Gill net: That this program be continued.
- e. Beach seining: That any formal proposals be tabled until DMF has attempted some experimental sets to gather information on Menidia,(Atlantic silverside).
At this point Robert Lawton interjected with a report on the ex-I Six sites were found to be suitable in the Plymouth-Kingston perimental sets. Duxbury Bay area; three open coastal stations and three estuarine sites. Two nets were utilized, a 20' and a 50' net. A series of sets were made at each station 15 to 30 minutes apart. Silversides were counted and released. Don Miller suggested that Dave Bengston from the EPA Narragansett lab be consulted on Menidia sampling.
- f. Creel Survey: That BECo reinstate the survey if it wishes. Robert Anderson commented that a creel survey has good public relations value, but funding would probably not be available,
- g. Smelt: EPA (Leger) advised that although that 1979 smelt study has been beneficial and has provided much useful information on the Jones River smelt stock, it will not be required as a condition for continued plant operation. Bob Anderson suggested continuation of the study one more year at the level of the 1979 study. A recommendation was tabled, but there was support among some members for another year of work at the same level of involvement.
A discussion then ensued amongst committee members. Robert Anderson said that unless the study 'is required by the regulatory agencies, BECo would I be hesitant to fund the work unless strong justification was evinced. Clint Watson felt the study should be continued because as of yet the new sluiceway has not been built, and its effectiveness to reduce impingement mortalities must be subsequently evaluated over time through survival studies. Chairman
- I Bridges recommended the issue be readdressed by subcommittee action. This body should decide what modifications would be made if the study is to continue.
He opined that we should ascertain impact of smelt impingements on the local population which at present is not known. C. F. Cole motioned that the issues of local seining and smelt studies be discussed further at a forthcoming sub-committee meeting. He also motioned that the creel survey be deleted, but that all other studies continue per subcommittee recommendations. Al Eipper second I l the motion, and it was passed by all voting members. l Meeting adjourned 3:20 P.M. 1 1 1
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ADMINISTRATIVE - TECHNICAL i l COMMITTEE MEETING )' Septerier 12, 1979 I. I
- R. D. Anderson BECo l
! Cathy Chabot DMT i l Fred Lux NMFS Al Eipper FWS l Allen J. Ikalaine: EPA l
! Robert Leger EPA l Clint Watson MDWPC l
i Lewis N. Scotton BECo Christine C. Sheehan DMT Don. C. Miller EPA Ruth Rehfus NMTS Leigh Bridges DMr j ) Wayne R. Davis EPA l Robert Lawton DMT
, char 1es r. c.1e u. MASS.
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I MEMOPANDUM T0: Members of the Administrative-Technical Committea, Pilgrim Power Plant Investigations FROM: Phillips Brady, Marine Fisheries Biologist, Massachusetts Division of Marine Fisheries
SUBJECT:
Addendum to the Forty-fourth A-T Minutes DATE: December 10, 1979 The minutes of the forty-fourth A-T Ccamittee meeting are corrected as follows via this addendum. Page 1. Item I. The incorrect spelling of "proferred" is corrected to proffered. Item II, section b) Irish Moss Landings. The last sentence should read, "No adverse PNPS impact was apparent except in the I immediate vicinity of the discharge plume". Item III, section c) the last sentence of the paragraph should I read "Mean catch per tow increased from 1978 levels as follows: winter flounder -10.8 to 19.5, skate -3.4 to 14.0, windowpane -1.6 to 3.8, longhorn sculpin -1.1 to 3.0, yellowtail -2.2 to 7.2, and ocean pout -1.5 to 4.8." Page 3. Section III. Progress Repcrt - Editorial Subecmmittee. The word I "obatined" in the last sentence of the paragraph is corrected to obtained. Section IV. Sluiceway Update - Sentence five, of the first para-I graph should read, " Impinged fish and debris will fall into a four to ,six inch (water depth), deep sluiceway trough made of corrugated sheet metal to reduce water velocities". The first sentence of paragraph two is corrected to read " An alternate system will remain in use to shunt large I quantities of debris into a collection pit during storms". Page 4. Item V, section b) the word analycing in the second sentence is hyphenated as follows ana-lyzing. Also the word reasonable in, sentence one of paragraph three is spelled and hyphenated as follows rea-sonable. I
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l l l Page 5. Item IV, section 4b) shall read "Finfish observations: That this g l program, begun in 1978, be continued for at least another year to build experience." Also in section 4 e paragraph 3 i two the fourth sentence should read "A series of sets was
- made at each station 15 to 30 minutes apart".
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E E. MEMORANDUM TO: Merlers of the Administrative-Technical Ccmmittee, Pilgrim Power Plant Investigations TROM: Phillips Brady, Marine Fisheries Biologist I
SUBJECT:
Minutes of the forty-fifth meeting of the Administrative-Technical Committee, Decerter 7, 1979 DATE: Decerter 10, 1979 The forty-fifth Administrative-Technical Committee meeting was called to order at 10:10 A.M. in the Boston Edison Company (BECo) offices by Chairman Bridges. Eight agenda items were addressed:
- 1. Minutes and documents a) Corrections of the forty-third Committee minutes were tendered and are found in the attached addendum.
b) Members received copies of materials from Marine Research, Inc., on
" Investigations of Larval Winter Flotc. der in the Plymouth Harbor-Duxbury Bay (PHDB) Estuary April-June 1979", and a " Proposal for Assessment of Fish Survival at PNPS Screen Wash Sluiceway", plus an outline letter from Mr. Scherer to Mr. Scotton discussing the larval flounder studies. Also dispensed were copies of reports from the Fisheries Subecmmittee, the Benthic subec=mittee, and a five page schematic illustrating the location and parameters of the screen wash sluiceway currently under construction at PNPS.
II. Review and discussion of the semi-annual report a) On page one,of the benthic report the last sentence of the first paragraph, the word "if" should read "is". b) The Minutes of the forty-second A-T Committee meeting were misplaced, appearing before the P. A.T.C.' minutes tab instead of after. Al Eipper offered a correction on page II-1, of the intrnduction, stating that in the last sentence of the page, the "U.S. Bureau of Sport Fisheries and
'dildlife" should now read the "U.S. Fish and Wildlife Service".
Bob Anderson directed attention to the subb :t areas reported by BECo's environmental services group, noting that this wa. the first time that Fish Surveillance Studies had appeared in the-semi-annual report.
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III. Discussion of 1980 finfish studies othcr than Marino Fishorics a) Bob Anderson reviewed three studies and requested ccmmittee support for continuation. The first was that the fish impingement study be maintained at the present level for 1980. Bob Lawton moved that the impingement study be continued at last year's level of effort. Al Eipper second this motion. Vote: Motion was passed unanimously by voting members - one abstention. Second, the fish overflight studies and third, the continued main-tenance of the barrier net were presented. Bob again requested that these work areas be continued at the same effort level. He noted that the barrier net appears to be fulfilling its purpose successfully but has not yet been critically tested. Bob Lawton moved that both programs be continued at the present level of effort for 1980. The motion was second by Ruth Rehfus. Vote: Motion passed by voting members unanimously, with one g abstention. 5 b) The Division of Marine Fisheries' studies were discussed. Chairman Bridges stated that Division proposals are currently being prepared for continuing studies, c) Lew Scotton presented the propcsal for the Entrainment study following the framework established at the last A-T Committee meeting. He re-quested additional input, but no further discussion was forthcoming. Bob Lawton moved that the study continue, adhering to the schedule previously presented by Lew. George Kelly second the motion. Vote: Motion passed unanimously by voting members - one abstention. d) The 1980 Winter riounder Larval Stady. Lew discussed the present investigation of larval winter flounder in the Plymouth Harbor- 1 xbury I Bay Estuary which was conducted by Marine Research, Inc., of Talmouth, Mass. The first area addressed was the discontinuation of the larval winter g f1cunder study as it currently exists. This study was felt to have 3 fulfilled its' designed objective, via the four years of data col-1ection, and would provide minimum new informatien if continued in I D
the present mode. Consequently, it was felt that tne study should be rescoped to address survival and condition of larvae flushed from the PHDB region. I Subject areas addressed were: I 1) The condition of flounder larvae, leaving PHDB estuary prior to being subjected to plant effects. I 2) Areas north of PHDB will also be considered to determine possible recruitment of larval flounders to the environs of PNPS. Techniques to be utilized include:
- 1) Use of otoliths for both larval age determination and delineation of daily rowth patterns.
I 2) Analysis of larval gut contents for determination of possible diet change as a precursor of natural mortality.
- 3) The utilization of PNA, DNA ratios to aid in determination of larval condition inside and outside of PHDB area. Bob Leger I asked if this study was being proposed to the committee by BECo. Lew replied yes, with the recommendation from Marine Research, Inc. The MRI proposal will be distributed to committee members in the future with a two to three week period for pessible I comments and revisions.
Fred requested that the full proposal be sent to committee mem-bers and reviewed. Discussion could follow at the next A-T meeting in February. Pete Cole moved that the committee suoport the proposed stud flounder larvae in principal, fed a single spawning season, y of approximately April through June, 1980. Ruth Rehfus second the motion. --- Vote: The motion passed unanimously by voting members - one I abstention. IV. Benthic Study Report Don Miller presented the Benthic subcommittee report, formulated after two meetings at the Narragansett laboratory. The subcommittee addressed two problem areas:
- 1) The lack of integration of previous benthic studies.
I Past work was reported as discrete study units with ' En a comparison or compilation.
- 2) A paucity of pertinent data from *% ir .cted area excluding that of I the established ten-foot statie;.
The Committee seeks to rectify this situation through thorough exami-I nation of existing data, and the collection of additional current information. Two objectives were stated: a) Locate t a area of maximum effect of the thermal plume using the greatest number of biological and physical parameters feasible. b) Spatially detail the extent and type of plume-related effects that have occurred over time. The subcccmittee proposed that through work conducted under next year's Benthic contract, the contractor consolidate existing infor-mation, and construct an integrated map of information detailed to g date. Secondly, the work should obtain additional data in the near g field area. This information will assist in characterizing total plant impact on the benthic community, while relieving the dilemma of data paucity. It is believed that this work will allow more intelligent se; sing of future benthic work. The urgency of action on this study propcsal was stressed, due to the difficulty of data collection while the plant is on line, and the opportunity offered in the coming =cnths while the plant is shut down for refueling. Bob Leger stated that the Benthic subecesittee was charged with determining plant impact on the benthos. The proposed study will provide additional data to definitively determine benthic impact. Dick McGrath of TAXON responded to queries from the committee con-cerning the manner in which the work would be transacted. Dick stated that the major thrust of the preposed study was field oriented. Should the study commence on schedule, he saw no difficulties in providing a report to the committee and BECo in time for any re-scoping of studies for next year. George Kelly moved that the committee proceed with this new benthic 5 concept and allow the subectmittee to pursue it to the point of BECo 5 establishing a working contract, contingent upon full continuation of existing studies. mm Clint Watson second the motion. Vote: Motion passed unanimously by voting members - one abstention. George also moved, "that the committee delegate full power to the sub-committee in regards to firming up the complete and finished study" Fred second this motion. I _4_ I I
Clint voiced his reservation to this, and opted for the entire committee to rule on any possible study modifications. The motion was withdrawn after i further discussion. Lew Scotton requested that any committee members wishing l to comment on the benthic subectaittee report should contact him on or before l December 13, 1979. Otherwise the proposal would be considered acceptable as presented. I 1 V. Up-date on Sluiceway Construction I Bob Anderson pres:nted an up-date on the progress of the temporary sluice-way requested by EPA and MDWPC. Presently, the sluiceway is approximately 70% completed. The sluiceway consists of a solid concrete corrugated structure. The trough will have a minimum water depth of 4-5 inches, with a velocity of I 8 ft/sec or less. Specific conditions of water flow and depth were selected to maximize fish survivability. When Unit II is constructed, there will be an additional section of sluiceway constructed, and the present structure will be discontinued, with Units I and II discharging concurrently. The proposal of Marine Research, Inc. for assessment of fish survival at I PNPS once the sluiceway is operational was discussed. Bob requested that the proposal be reviewed by committee members, and any comments or suggestions be offered by Dec. 14, 1979. Bob Leger asked why there is a 55-hour period being utilized for deter-mination of delayed mortality. Bob replied that this period is utilized because it coinsides with the time that personnel are there for routine screen monitoring. Bob Anderson and Lew Scotton will report on the data to be collected by MRI. Monthly progress I reports and two semi-annual reports (#16 and #17) will be prepared. Bob extended an invitation to all interested committee members to view the completed sluiceway when it commences operation. , Fred noted that the plant will be shutdown for 94 days commencing January I Sth. before the plant goes down or after it comes back on line.With this in mind, it was suggested I Fred remarked that BECo is still forecasting commencement cf construction work by 1 April 1990 for Unit II. permit issuance by the NRC. Plans are felt to still be in queue for Though there is no official freeze on permits, there is an unofficial moriterium in effect until the NRC's reorganization is conpleted. Bob Leger asked if Fred expected BECo to receive a construction permit from the NRC during the first six months of next year. Fred stated he could not answer the question at this time. Leigh inquired about the storage of spent fuel an site. Fred stated that all spent fuel must be maintained on site and that there is sufficient room for I I _ I .
additional storage for approximately 15-20 years. VI. Fisheries Subcommittee report on smelt and silversides Pete Cole presented his memorandum of the October 19, 1979 meeting of the fisheries subcommittee during which the smelt study and silverside work was discussed. The proposed work with the Atlantic silverside was withdrawn following considerable discussion. Bob Lawton presented the smelt study proposal to PATCO, as recommended by the subcommittee and outlined in a draft research proposal. . The et ::ives of the work were presented as follows: a) Peinforcement of identified trends in baseline data provided last year, through additional observation and sampling. b) Confirmation and enlargement of parameter values of the Jones River smelt population via natural history cnd fish stock dynamics. c) Approximation of " ground truth" parameters oi this population by pooling multi-year data. d) Development of a population dynamic life table for the Jones River Population. e) Provision of accurate local data for use in mathematical modeling by BECo to predict plant impact on the affected population with more accuracy. E W Sob stated that Pilgrim I does impinge young of the year and one year old g smelt which are not considered via the model employed in the 316 document. g This defect may impart inaccuracies to prediction of maximum impact. f) Utilization of representative smelt to provide control specimens for the Padiological Control Testing program. g) Estimation of prolarval production, egg survivorship, and accurate calculation of total egg production. h). Estimation of population sice for 1990. George Kelly noted that the fisheries subcommittee fully supported the con-tinuation of the smelt study. He moved that 'the A-T Committee support a 1980 study continuation as presented by Bob in his working draft. Pete Cole second the motion. I
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Vote: The motion passed unanimously by all voting members - one abstention. I I W E
VII. Other Business I Leigh presented the proposal and application for assistance in the publi-cation of the Final Report through the Office of Coastal Zone Management. Total cost was set at approximately $67,700, 20% of which must come from matching funds other than federal monies. Agencies which have agreed to provide funds for publication are: MDMF $ 6,000. I MDWPC Fish and Wildlife 2,000. EEI 6,000. 1,000. Total $15,000. The amount required to fulfill the match is placed at $13,340. Leigh hoped to hear on the propesal within a month. If approved he felt the funds would be needed rapidly. Work was envisioned to co=T.ence on Feb. 1, 1980 and cover an 18-conth period. A convening of the editorial subec=mittee was proposed for the near future. VIII. Adjournment 'E5 Meeting adjourned at 15:20. I I I I ' l i I I
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Administrative-Technical Cormittee Meeting December 7, 1979 Phil Brady R.D. Anderson Mass. Division of Marine Fisheries Al Eipper I BECo Bureau of Sport Fisheries & Wild-( Bob Leger life Clint Watson EPA Don Miller Mass. Control Division of Water Pollution " Wayne Davis EPA EPA Robert Lawton F Charles F. Cole Mass. Division of Marine Fisheries h Lewis N. Scotton University of Massachusetts F.J. Mogolesko BECo Ruth Rehfus BECo r Leigh Bridges NMFS, Gloucester ( George Kelly M. Ross Mass.NMFS, NEFC, Division Woodsof Marine Hole Fisheries M. Scherer University of Massachusetts Dick McGrath MRI TAXCN Christine Sheehan Sue Faria { Mass. Mass. Division of Marine Fisheries Division of Marine Fisheries gee, e*
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