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Environ Studies,Plankton,Jul-Dec 1977
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Issue date:	06/30/1979
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I I

I SEABROOK ENVIRONMENTAL STUDIES, JULY THROUCH DECEMBER 1977

)

PLANETON TECHNICAL REPORT IX-1 I

I Prepared for PUBLIC SERVICE COMPAflY OF NEW HAMPSHIRE Manchester, flew Hampshire I

by NORMANDEAU ASSOCIATES, INC.

Bedford, New Hampshire I

June 1979 I

I KOhhh4k3 I

PDR

I I

TABLE OF CONTEllTS PAGE

1.0 INTRODUCTION

........................ 1 2.0 METHODS........................... 3 2.1 FIELD COLLECTIONS................... 3 2.1.1 Pump Samples: flet Phytoplankton and Macrozooplankton................

3 2.1.2 Whole Water Samples: Phytoplankton, I

Chlorophyll a, Nutrients and Primary Productivity 3 2.1.3 Net Tows: Macrozooplankton........... 6 2.2 LABORATORY ANALYSES.................. 6 2.2.1 Net Phytoplankton................ 6 2.2.2 Whole Water Phytoplankton............ 7 2.2.3 Chicrophyll c and Nutrients........... 7 2.2.4 Primary Productivity.........

8 2.2.5 Macrozooplankton................ 8 3.0 RESULTS AND DISCUSSION................... 9 3.1 PHYTOPLANKTON..............

9 3.1.1 Re s u l t s..................... 9 3.1.2 Discussion..................

12 3.2 ZOOP LAN KTON.....................

16 3.2.1 Results....................

16 i

3.2.2 Discussion...............

23 4.0

SUMMARY

...................25 l

5.0 L IT ERATU R E C I T ED.....................

2 6 I

APPENDICES........................

27 l

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LIST OF FIGURES PAGE 2.1-1.

Plankton sampling stations..............

5 I

LIST OF TABLES I

PAGE 2.1-1.

Plankton sampling schedule........

4 3.1-1.

Abundances (cells /l) of whole water and net phyto-plankton at each station and depth..........

10 3.1-2.

Numerical abundance (cells / liter) of net phytoplankton 11 I

3.1-3.

Numerical abundance of whole water phytoplankton...

13 3.1-4.

Primary productivity, biomass, phaeophytin, ratio of I

productivity to biomass, temperature, salinity ortho-phosphate, nitrate, nitrite, and ammonia at Stations 2 and 5........................

14 I

3.2-1.

Relative proportions of holoplankton, peroplankton and tychoplankton by collection date for microzooplankton and macrozooplankton.................

18 3.2-2.

Abundances of total microzooplankton and macrozooplankton at each station and depth...............

19 3.2-3.

Abundances of microzooplankton at Station 2, surface and bottom...............

20 3.2-4.

Dominant taxa and maximum densities from each sample type and plankton component......

21 3.2-5.

Abundances of macrozcoplankton taxa at Stations 2, 5 and 6........................

22 I

I I

ii I

I I

SEABROOK ENVIRONMENTAL STUDIES, JULY THROUGH DECEMBER 1977 F[ S.N KTON I

TECHNICAL REPORT IX-1 I

I

1.0 INTRODUCTION

I Since 1969, plankton studies designed to establish a pre-operational data base of species occurrence, abundance and distribution have been conducted in the Hampton-Seabrook estuary and nearshore waters.

A formal preoperational program was instituted in July 1975, resulting in two July-June annual reports (NAI, 1977, 1978). Report IX-1, compiled to shift subsequent reporting periods to a January-December annual cycle, presents plankton results from July-December 1977 and includes I

comparisons to the two previous years of formal preoperational monitoring.

The plankton program includes zooplankton, phytoplankton and ichthyoplankton studies in addition to chlorophyll a, primary productivity and nutrient measurements; ichthyoplankton results are presented with the finfish program. Beginning in July 1977, the phytoplankton sampling regime was expanded to include whole water samples in addition to 76 um net samples. The whole water samples are designed to sample small

(<76 pm) species

(= nanoplankton) not captured by the net.

For zooplankton I

sampling a 505 pm meter net replaced a 333 pm Bcnge net to sample macro-rather than meso-zooplankton. The 76 un phytoplankton and zooplankton pump samples, collected during the nig'it in previous years, are now collected during the day.

I The net phytoplankton assemblage in the Gulf of Maine and specifically in coastal New Hampshire is composed largely of diatoms and I

2 I

armored dinoflagellates (NAI, 1977). Diatoms typically reach peak abundance levels in spring and fall with minima occurring in winter and Dinoflagellate densities tend to reach peak levels during the su==er.

warmer months. Maximum concentrations of the critical plant nutrients, nitrogen and phosphorous, often occur in winter, when low light levels tend to limit phytoplankton growth (NAI, 1977). Net phytoplankton species that have been abundant during certain seasons each year and were selected as indicator species include: Skeletonema costatum (late summer and late fall), Chaetoceros debilis (spring) and Ceratium longipes I

(early su=mer).

Patterns of zooplankton abundance are more complicated.

Populations of holoplankton, composed mostly of herbivorous or omni-vorous copepods, tend to follow the phytoplankton peaks. Four indicator species have historically exhibited the following distributional trends:

Oithona similis, ubiquitous; Eurytemora herdmani, inshore and in summer; I

Pseudocalanus spp., offshore and in late summer and fall; and Calanus finmarchicus, offshore and from spring to midsummer. Among the more abundant meroplankton are the larvae of bivalve molluscs, gastropods, barnacles and polychaete worms.

Because meroplankton includes the young of many econcaically important shellfish such as clams, mussels and decapod crustaceans, as well as finfish eggs and larvae, it is given particular emphasis. The tychoplankton includes harpacticoid copepods, nematodes, mysids, amphipods, cumaceans and juvenile deca:od crustaceans.

The zooplankton, like the phytoplankton, exhibits defined seasonal I

trends in the Gulf of Maine.

I I

I

3 I

2.0 METHODS 2.1 FIELD COLLECTIONS plankton samples were taken twice monthly from July through December 1977 as indicated in Table 2.1-1 at Stations 2, 5 and 6 (Figure 2.1-1).

I 2.1.1 Pump Samples: Net Phytoplankton and Microzooplankton Four replicate submersible pump samples were collected during daylight hours at Station 2,1 m below the surface and 2 m above the bottom (Figure 2.1-1). Each pump discharged on deck into its own small, 76 pm mesh plankton net, set into a specially designed stand that filled with seawater to within 15 cm of the top of the net.

Each net was fitted with an 8-dram (33-ml) vial on its cod end.

The volume filtered was approximately 100 liters. Contents were thoroughly rinsed from the nets after pumping, and fixed in borax-buffered 5% formalin.

I 2.1.2 Whole Water Samples:

Phytoplankton, Chlorophyll a, Nutrients and Primary Productivity I

Near-surface (1 m) and near-botton (2 m above) water samples I

were collected during daylight. hours with either a submersible pump or water sampler at Station 2; at Station 5, only near-surface samples were collected. From all whole water collections, 2 one-quart jars containing 50 ml of Lugol's iodine fixative were filled for phytoplankton taxonomic analysis. From monthly near-surface collections at both Stations 2 and 5, 1 gallon was reserved for chlorophyll a determinations, 250 m1 frozen as soon as possible for nutrient analyses and 400 ml reserved for pH I

determinations; in addition, four 250 ml EOD bottles (2 light ard 2 da.rk) were prepared for primary productivity experiments.

I

TABLE 2.1-1.

PLAtlKTON FAMPLING SCllEDULE. SEABROOK ECOLOGICAL STUDIES, JULY TilRC'.iH DECEMBER 1977.

Wil0LE WATER Wil0LE WATER PilVTOPLAllKT0fl PUMPED PLUS 1 m 505 pm flET PHYTOPLANKTgri a

c DATE SAMPLES SAMPLES WATER SAMPLES SAMPLESd STATION STATION STATI0ft STATION 6 July 2

2, 5

2, 5, 6 20 July 2

2 2,

5, 6 3 August 2

2, 5

2, 5, u 23 August 2

2 2,

5, 6 7 September 2

2, 5 2,

5, 6 23 September 2

2 4 October 2

2, 5

2, 5, 6 18 October 2

2 1 November 2

2, 5

2, 5, 6 23 November 2

2 15 December 2

2, 5 2, 5, 6 27 December 2,

5, 6

not phytoplankton and microzooplankton (>76 um) whole water ;hytoplankton only primary productivity, chlorophyll a, and nutrients macrozooplankton (and ichthyoplankton) primary productivity only on 8 September.

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ftACR0Z00PLAflKT0fl AtlD ICHTHYOPLAllKT0fl STATI0ftS Figure 2.1-1.

Plankten sampling stations. Seabrook Ecological Studies, July through December, 1977.

I I

6 I

At Stations 2 and 5, temperature and conductivity profiles were made with a Beckman thermistor / salinometer (Model RSS-3). Duplicate dissolved oxygen samples and a salinity sample were also collected near surface and near bottom.

I 2.1.3 tiet Tows: Macrozooplankton Four replicate sequential oblique :.ows were made at night at Stations 2, 5 and 6 with 1 m diameter 505 pm meshed nets. Each tow was 5 or 10 minutes in duration depending on plankton densities and was taken I

from approximately 2 m off the bottom to the surface. The volume filtered was estimated with a General Oceanics digital flow meter. Upon retrieval, each net was thoroughly washed and the contents fixed in borax-buffered 5 to log (depending on plankton density) formalin.

I 2. '.

LABORATORY AtlALYSES I

2.2.1 flet Phytoplankton and Microzooplankton

let phytoplankton taxa from pump samples (2 field replicates from each depth) were enu.nerated from two independent, one-ml subsamples in a Sedgwick-Rafuer counting cell.

Each subsample was placed under a compound microscope at 100X and three random passes across the width of the Sedgwick-Rafter cell examined. IIet phytoplankton cells were identi-j fied to species as far as practical.

l l

From pump samples,all four field replicates from each depth l

were analyzed as follows for microzooplankton:

the volume of the vial l

was concentrated to a known amount based upon the relative settled volume of the plankton and detritus. Tne sample was agitated with a l

calibrated bulb pipette in an attempt to homogeneously distribute the l

contents. A 1 ml aliquot was quickly removed and placed in a Sedgwick-1 l

Rafter cell and examined under a compcund microscope. Zooplankton taxa l I 1

l

7 I

were identified using magnifications of 40X to 200X. Aliquoting and enumeration continued until 300 to 400 organisms had been counted; the entire sample was enumerated when less than 300 organisms were encountered.

I 2.2.2 Whole Water Phytoolankton Whole water collections were reduced to sample volumes of 33 mi by decanting the Lugol's-preserved liquid af ter the plankton settled. The sample was placed in an 8-dram vial and mixed by inverting 30 times. Two 0.1-ml subsamples were withdrawn and each placed in a I

Palmer-Maloney counting cell. Each subsample was examined under a compound microscope at 200x, and the entire contents counted and identi-fled to the lowest practical taxon.

During counting, cells and chains were classified by means of a 76 um ocular micrometer grid into two size classes (greater than or less than 76 um).

I 2.2.3 Chlorophyll a and flutrients Chlorophyll a water samples were divided into four 900 ml sub-samples and filtered through a glass fiber filter. Near the end of filtration, 2 ml of saturated MgCC soludon was added to retard sample 3

degradation. Glass fiber filters were frozen pending laboratory extrac-tion of pigment. Extraction of plant pigmen. consisted of macerating the filter in 90% aqueous acetone and centrifuging. Following extraction, fluorescence was determined before and after acidification (with 5% hcl)

I using a Turner fluorometer which had been calibrated spectrophotometrically (EPA, 1973; Strickland and Parsons, 1972). Chlorophyll a and phaeophytin concentrations (mg/m ) were ccmputed.

Water samples were also analyzed for the following series of plant nutrients utilizing a Technicon Autoanalyzer system and EPA I

Methods (1974).

I I

8 l

l NUTRIENT METHOD I

total phosphorus persulfate digestion in block digester followed by automated colorimetric ascorbic acid reduction I

orthophosphate automated colormetric ascorbic acid reduction i

f nitrite automated cadmium reduction, witboat cadmium column in place nitrate automated cadmium reduction ammonia automated idophenol blue Concentrations were expressed as ug/l.

2.2.4 Primary Productivity Samples were inoculated with five microcuries of C as sodium bicarbonate as soon as they arrived at the laboratory,and incubated for I

four hours at ambient seawater temperature in a flow-through temperature box with 1000-1200 lux fluorescent illumination. Samples were.then fixed with 2 ml of 40% formalin, filtered through a 25 r:m Millipore membrane filter (0.45 um pore size) at about 15 psi, dried on a planchet I

in a desiccator and counted using a Muclear Chicago Model 186 gas flow scintillometer. Primary productivity was calculated as mg C/m /hr (Strickland and Parsons, 1972). Productivity to biomass ratios were a

computed as mgC/m /hr divided by mg chl a/m.

I 2.2.5 Macrozooplankton Each sample to be analyzed was split using a Folsom Plankton i

Splitter into fractions which provided counts of at least 30 individuals of each species to be identified; generally, no more than 1/4 of the original sample was analyzed. Zooplankton taxa were enumerated by species and general life stage,when practi u,".ci - dissecting microscope

.Three of the four 1 m 505 um meshed net tows at eaca station were randomly selected for macrozooplankton analysis on all sampling dates (Table 2.1-1) except on 27 December, when only Station 2 was analyzed.

9 I

at magnifications between 6x and 150x. Selected taxa (Crangon septem-spinosa, Cancer spp., Neomysis americana and Euphausiacea) were identi-fied to detailed developmental stage. Neomysis americana only were identified as immature, male, female (ovigerous or larvigerous); carapace length was measured to the nearest 0.1 mm and brood pouch contents were counted.

If copepod taxa were considered rare, they were sorted and counted (at least 30 of each indicator species) frcm an appropriate split; if abundant, up to 3 one or twc-ml aliquots were quickly removed with a Stempel pipette from the recombined sample of known volume.

Abundances (individuals /1000m ) were computed.

I 3.0 RESULTS AtlD DISCUSSI0tl I

3.1 PHYTOPLAi1KT0tl I

3.1.1 Results Total net phytoplankton abundance was low over the study period, with maxima of 728 cells / liter in July and 422 cells / liter in September (Table 3.1-1).

Of the 76 total phytoplankton taxa, 42 were captured in net samples (Appendix Table 1).

Abundances are presented for those taxa comprising either more than 10% of total net density during any sampling period or more than 1% of total net density for the I

six month period (Table 3.1-2).

Five species including, Ceracium longipes, Coscinodiscus sp., Chaetaceros tores, Guinardia flaccida and Chaetoceros affinis exceeded an average of 100 cells /1 overall, and represented 76% of the total net phytoplankton over that six month period. Species dominating samples during peak density periods were Ceratium longipes in July, Chaetaceros teres and Guinardia flaccida in September, and Coscinodiscus sp. in Novemoer/ December.

I Total phytoplankton densities from whole water samples exceeded l

4x10 cells / liter in October and November at Stations 2 and 5; maximta

N. americana data will be presented in the 1978 Anrual Reports.

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TABLE 3.1-1,.

ABUilDANCES (cells /1) 0F WHOLE WATER AND NET PilYTOPLAtlKTO.i AT EACil STATION AND DEPTil.

SEABROOK ECOLOGICAL STUDIES, JULY TilROUGli DECEliBER 1977.

l l

JULY AUGUST SEPTEMBER OCTOBER t:0VLMBE R DECEMBER l

i DATE 7/6

//20 8/3 8/23 9/1 9/23 10/4 10/18 11/1 11/23 12/15 f

NET PHVTOPtANKTON LTATION 2 Surfacw 0

244 26 30 422 140 121 250 30'J 374 39 butt p 728 1 37 7

68 41 150 23 82' 99 29 244 WitOt t WATER H

PHY10 PLANKTON O

j STAT 1vN 2 Sun f.ase 1,320 1,810 1,650 11, %d 61,820 41,7HO 68,200 2,947,120 1,831,410 404,5R0 8,910 bott(m 12 t t,0 2,130 4,510 10,230 20),390 12,870 7.h10 2 3t>,8 30 173,030 13,200 9,020 1

STATI(h S I

I surface 1,100 NS 7,040 NS 42,020 NS 331,560 N3 1,07),460 NS 7,590 N: =rva t samraed i

5 1

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M TABLE 3.1-2.

fluf1ERICAL AButlDAflCE (cells / liter) 0F flET PHYTOPLAflKT0ft, ilAVIllG DEllSITIES OF EITilER

>10% DURIllG AI!Y SAfiPLIllG PERIOD OR >l% OF TOTAL DEllSITY FOR Tile EllTIRE COLLECTI0ft PERIOD, AT STATI0fl 2 SURFACE AtlD BOTT0fi. SEABROOK ECOLOGICAL STUDIES, JULY TilROUGil DECEf1BER 1977.

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density (4x10 cells / liter) was recorded at Station 5 in November (Table 3.1-1).

Of the 76 total taxa, 52 were collected in whole water samples.

Taxa considered dominant (>10% of any whole water sample or >l% of total whole water phytoplankton during the 6-month period) are presented in Table 3.1-3.

The five most numerous taxa, each representing greater than 1% of total whole water phytoplankton, were olisthodiscus luteus, I

Prorocentrum triestinum, Skeletonema costatum, Peridinium trochoideum and Guinardia flaccida; collectively they represented 96% of the whola water phytoplankton. Peak uhole water phytoplankton densities recorded in November at Stations 2 and 5 and in October at Station 2 were domi-nated by Olisthodiscus luteus in surface samples. Protocentrum spp.

and Rhinosolenia delicatula aho contributed to high denaities recorded in October and November at Station 2 (Table 3.1-1, 3.1-3).

I Biomass (chlorophyll a) and primary productivity (carbon 14 uptake / hour) peaked in November and declined to mir.imum values in December (Table 3.1-4), generally corresponding to whole water phyto-plankton abundance trends, but not to net phytoplankton densities.

Nutrient studies (Table 3.1-4) indicated that peak concentrations of orthophosphate, ammonia and nitrite were not well-defined. Nitrate peaked in December following the phytoplankton bloom, while maximum total phos-chorus concentrations generally occurred during November and December.

Lowest values for orthophosphate, total phosphorus and nitrate were I

found in July.

I 3.1.2 Discussion I

Densities of net phytoplankton were low from July through December 1977.

In 1976, although densities were considered low relative I

to 1975 (NAI, 1978), they exceeded 1,000 cells / liter frequently and 2,000 cells / liter in several instances. Maximum 1977 densities were less than 800 cells / liter. Total phytoplankton (whole water) densities were generally two orders of magnitude greater than those in net phytoplankton samples. The whole water method, instituted in July 1977, captures E

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..i-;~;12 E,E-;~~I i,a ;~;32 ;0

=OM g 422.))&.4214

- a 2'W333.32%.

M e

2 24434133':34 M

eto

=

e g

E M

I s

3 8

E 4

o =

.2 a

2 a o a

e 3

3 3

. m o LLJ

-.J I

CG CC H

I I

m M

M M

M 3

3 TABLE 3.1-4.

PRIftARY PRODUCilVITY (ing C/m /hr), BI0t1 ASS (mg/m ), pilae 0PilYTIll (mg/m ), RATIO 0F PRODUCTIVITY TO BIO 11 ASS (C/Chl/hr), TE!1PERATURE ( C), SALINITY (0/oo), ORTl10Pil0S-PHATE..llITRAlE, (pg/l), IllTRITE (pg/1), AND Allt10 illa (pg/1) AT STATIONS 2 AflD 5.

SEABROOK ECOLOGICAL STUDIES, JULY TilROUGH DECEliBER 1977.

PRIMARY RATIO Of PRODUCTIVITY PRODUC'lVITY TOTAL (ej C/m /hr)

BIOMASS TO ORTHOPHOSPHATE PHOSPHOROUS NITRATE NITRITE AMMONIA REPLICATE REPLICATE CHLOR 0P]LLa PHAIOPHYTIN Blut: ASS TIMPERATURE SALINITY P0 P TOTAL P NO -N NO -f4 NH DATE 1

2 (p3/m )

(C/Chl/hr)

(pgft)

(pg/l)

(pgfl)

(vgfl)

( pgf-lN

}

6 July 1971 STA J 1.31 1.28 0.53t 06 0.28

.06 2.44 11.3 31.6 0.0 6.0 6.0 3.0 no data STA 5 1.50 1.23 0.571.05

0. 38

.09 2.40 10.5 31.6 7.0 9.0 6.0 1.0 no data 3 August 10

ETA 2 4.37 4.34 1.25t.OH 0.65

.u4 3.48 11.0 II.s 10.0 16.0 6.0 1.0 rio data STA 5

.4.b5 3.32 1.12t.05 0.79

.04 3.56 10.9 31.9 16.0 22.0 11.0 2.0 rwa data 7,8.5 mi e r 1977 STA 2 3.79 5.05 1.19t 11 0.39 04 3.71 13.9 32.0 16.0 29.0

<1u.0 1.0 20.0 J.

STA 5 3.54

.74 0.971.07 0.3s

.07 3.75 13.8 31.7 10.0 16.0

-10.0 1.0 60.0 4 Octotwr 1977 STA.

7.18 7.06

2. 4 3 t. ss 1.22

.06 2.93 11 9 31.8 16.0 19.0 20.0 4.0 50.0 STA 5 6.39 ti. 4 3 2.46!.19 1.26

.v6 2.61 11.H 31.9 20.0 26.0 20.0 4.0 40.0 1 Novemk r 1977 STA 2 11.21 12.13 12.4d?.49 4.39

.58 0.94 10.5

$0. 9 19.0 41.0 10.0 1.0 30.0 ETA >

10.91 12 53 14.28?.b1 5.u3

.77 0.82 10.4 30.7 14.0 22.0 lo.1 1.0 50.9 1$ tw<:sa,er 1977 STA 2 1.39 NS 0.50t.07 0.55

.08 2.78 5.2 32.1 4.0 46.0 140.0 4.0 30.D STA 5 1.09 NS 0.41t.25 0.67

.35 2.06 4.4 31.6 15.0 25.0 9u0.0 3.0 10.0 averaged over all del.ths at 2 m 1ritervals from surface t o let tom.

NS = raut Sam}, led 1

4 4

15 I

small species not sampled by the 76 um mesh net, such as Olisthodiscus luteus (35 ym), Peridinium trochoideum (28 um) and Prorocentrum triestinum (18-22 um x 6-11 um). Skeletonoma costatum and Guinardia flaccida were collected by both methods but abundances were underesti-mated by nets. Both S. costatum and G. flaccida are chain-forming diatoms that may either pass through or be captured in net samples I

depending upon their orientation to the mesh. The most dense November-bloom, dominated by O. luteus, was only partially detected by the net samples. Consequently, the whole water method instituted to more carefully monitor the community, has provided information not available through pumped net phytoplankton samples.

I Dominant net species from July through December 1977 were similar to those recorded for the same period in 1976, except that Chaetaceros teres and Guinardia flaccida, although present in moderate numbers in 1976, were not previously considered as dominants.

In July I

1975 three characteristic species were selected as indicator specias.

The first of these, Chaetoceros debilis, did not appear as a dominant from July through December 1977; it was recorded once in net samples in September and was undetected in whole water samples. As seen in the first two years of the preoperational monitoring program, C. debilis blooms during spring with minor secondary peaks during November, and consequently is not expected to occur as a dominant from July-December.

I Skeletonema costatum, historically a late summer, early fall dominant with no clear depth preference, was prominent in September and October 1977 net surface samples, and October whole water surface samples.

Ceracium longipes was collected in highest densities in net and whole water July 1977 bottom samples. Historically (1975, 1976) it has been prominent during warmer months in near-surface waters.

I Spatial affinities were not generally apparent in July-December 1977 net samples.

In previous years net surface sanples usually had equal or greater densities than bottom samples. Whole water samples for 1977 generally showed that surface samples exceeded bottom samples by an order of magnitude, although individual samples varied between surface and bottom maxima. Ceratium longipes had historically shown a surface I

I

16 affinity during the ' armer months; in 1977 it wac collected in July bottom samples from both net and whole water programs. Skeletonema I

costatum had previously shown no clear depth preference; in September and October 1977, it was abundant in surface samples. Ollsthodiscus luteas, the main component of the November bloom, was predominant in surface whole water samples. Overall, it appears that there was a trend toward surface affinity in the community and in some select species.

I Maximal whole water phytoplankton densities and peak biomass values in November 1977 coincided with peak primary productivity and a low productivity to biomass (P/B) ratio. Monthly P/B ratios were similar through the sample period except during the November bloom, which suggests I

that cell " efficiency" (carbon uptake) was comparatively low in November.

Nutrient deficiency or reduced light (including turbidity caused by the high cell density), may have had an inhibitory effect on cell prolifera-tion; the lower November productivity per unit biomass was followed by a biomass decline in December.

In 1975 and 1976 biomass values peaked in March and September, I

respectively, coincident with high but not maximal net cell densities.

The better fit of 1977 whole water densities to biomass / productivity cycles may indicate that peaks in biomass are related to blooms of small-celled taxa not adequately sampled by the 76 pm net; consequently, net phytoplankton density maxima and peak biomass did not coincide.

Primary productivity has been highest in the fall of each year, preceded by a peak P/B ratio in 1976 and 1977. Possibly contributing to the late I

1977 fall bloom were high fall concentrations of some nutricnts including amonia, phosphate and orthophosphate. Nutrient concentrations which overall were high a the fall and early winter were generally simiJar to but not specifically consistent with previous vears observations.

I I

3.2 ZOOPLANKTON 3,2.1 Resul Ls Approximately 185 zooplankton taxa / life stages were identified and enumerated from 76 pm mesh net pump samples (microzooplankton) and

17 oblique 505 pm meter net tows (macrozooplankton) from July through December 1977 (Appendix Tables 2-4).

For all planktonic components, holo, mero-and tychoplankton, more macrozooplankton t u:a were collected than microzooplankton. The most diverse group overall (greatest number of taxa / life stages) were the tychoplankton which comprised 97 taxa I

and/or life stages, including crustaceans such as cumaceans, isopods, amphipods, mysids and harpacticoids; however tychoplankton contributed 2% to the total species density. The 45 holoplankton taxa / life stages, predominantly calanoid copepods, comprised 90% of the total zooplankton density (Table 3. 2-1). Forty-three meroplankton taxa and/or life stages contributed approximately 8% to total density and included larval hydro-zoans, polychaetes, gastropod and bivalve molluscs, barnacle and decapod I

crustaceans.

Microzooplankton were col.lected in greater density than 3

macrozooplankton (Table 3.2-2) : maximum densities were 3.7x10 /m (July) compared to 1.1x10 /m (October), respectively. Densities for both were maximal from July through September and declined to a December minimum. At Station 6, macrozooplankton abundance remained high through I

November due to higa centropages typicus densities. Differences in abundance of microzooplankton between surface and bottom waters were not marked, although for the first time bottom water affinities for some species were observed. Detection of depth preference changes may be related to the July 1977 change from night to day pump collections for phytoplankton, zcoplankten and water chemistrf.

I Dominant micro-holoplankton, largely compcsed of calanoid copepod nauplii and copepodites, displayed maximum abundances in summer,

'I and decreased to a December minimam (Tables 3.2-3, 3.2-4).

h'seudocalanus spp. copepodites were the only micro-holoplankters which showed a consistent depth affinity; they were collected most abundantly in near bottom waters on all sample dates. Tintinnids, Oithona spp. nauplii and cope-podites, and Temora longicornis adults also showed some affinity for near-bottom waters. Centropages spp. copepodites and unspecified meso-zoans were more dense in near-surface waters. Pseudocalanus spp. adults I

were more commonly found in near-bottom waters.

I I

m M

M M

M TABLE 3.2-1.

RELATIVE PROPORTIONS (% OF TOTAL) 0F ll0LOPLAliKTON,11ER0PLANKT0il Afl0 TYCl10PLANKTOM BY COLLECTI0il DATE FOR t1ICR0 ZOOPLANKTON AND 11ACR SEABROOK ECOLOGICAL STUDIES, JULY TilROUGil DECEMBER 1977.

SAMPLE DATE 7/6 7/20 8/3 8/23 9/7 9/23 10/4 10/18 11/1 11/23 12/15 12/27 Micr0z00 plankton

!!aloplankton 83.9 96.6 98.8 94.8 70.7 85.3 90.8 95.0 97,6 98.0 98.0 NS Meroplankton 15.8 3.1 0.7 1.5 29.1 10.5 6.7 3.5 1.d 1.7 1.4 NS Tychoplankton 0.3 0.3 0.5 3.5 0.2 4.2 2.6 1.5

' 4. 7 U.2 0.5 NS 4-...

Macr 0z0oplankton IIoloplank ton 89.7 81.0 76.2 74.1 09.2 NS 94.5 NS

%.9 NS 95.9 96.0 Meroplankton 10.2 18.0 23.2 25.7 10.3 NS 1.3 NS 0.2 NS

<0.1 0.1 Tychoplankton 0.1 1.0 0.6 0.2 0.5 NS 4.3 NS 0.9 NS 4.0 3.8 1

NS=not sampled

m m

m W

W M

M M

4 3

TABLE 3.2-2.

ABUNDANCES (no/m ) 0F TOTAL MICR0Z00 PLANKTON AND MACR 0700 PLANKTON AT EACH STATION AND DEPTH FROM JULY 1977 TilROUGH DECEMBER 1977. SEABROOK ECOLOGICAL STUDIES, JULY TilROUGli DECEMBER 1977.

AMP DATE TOW STATION DIPTH 7/6 7/20 8/3 8/23 9/7 9/23 10/4 10/18 11/1 11/23 Ic t o 12/27 Silk 4,720 76,200 22,600 3,970 11,600 11,900 8,870 13,500 11,400 29,600 1,b40 NS Micr0200 plankton 2

tuyr E6,0vo 30,$00 8,530 b6,200 75,600 20,500 9,080 4 100 3,970 3,170 2,990 NS (7h pm pamg> samplea)

. ]OO 53,400 15,f>00 35,100 43,600 16,200 9,000 8,800 7,700 16,40u 2,420 N.i 2

OBL 464 440 291 42) 5/6 NS 124 NS 17d NS 34 42 Mac rozooplank ton S

OHL 2t 6 502 1 86 316 32%

NS 173 NS 221 NS 12L NA H

(1 m, 50$ um net) 6 ObL 417 474 IN7 243 34)

NS 1,100 NS 404 NS Hu hA AVEkAGE 382 472 222 327 398 NS 466 NS 268 NS

&l 42 NS=not s.ampled NA=not analyzed

20 3

TABLE 3.2-3.

ABUNDANCES (no/m ) 0F MICR0Z00 PLANKTON (>10% ON ONE OR MORE COLLECTION DATES, OR SIX-MONTH ABUNDANCE >l%

OF TOTAL ABUNDANCE) AT STATION 2, SURFACE AND BOTTOM.

SEABROOK ECOLOGICAL STUDIES, JULY THROUGH DECEMBER 1977.

. I I

P SAMPLE DA'E T

TAXA H

7/6 7/20 8/3 8/23 9/7 9/23 10/4 10/18 11/1 11/23l12/15 I

Pseudocalanus/Calanus nauplit 5

10 21,000 2,180 17 2,6M 1, MO 1,240 1,330 385 9,670 391 B

93,500 1,680 795 4,070 0,s "

3,C90 320 1,680 2,020 1,250 1,470 Eseudocalanus spp. copepodite 5

C 15,7CO 4,300 0

61 set 259 42 52 015 76 I

B 69,80C 16,900 6,400 14,300 18,600 5.443 1,730 171 511 361 819 Olthona spp. naup111 S

411 17,646 8,880 871 4,020 2,1 L 1,060 4,100 6,330 6,650 620 B

19,000 263 14 1,010 3,120 1,863 2C4 90 95 191 86 Coceroda nauplii S

282 6,830 1,260 427 2,070 2,300 1,270 2,070 2,660 2,140 257 I

B 25,300 3,280 231 3,850 9,420 1,750 276 410 91 79 8

Tara lorrifcornis copepodites S

72 469 35 0

12 1,060 128 8

0 0

0 B

49,700 2,710 4

769 269 105 173 0

23 0

0 I

ofthona spp. copepodite 5

2,450 7,190 4,160 490 640 330 3,420 3,520 818 1,270 302 B

19,700

$99 65 645 1,100 2,850 1,030 198 240 364 56 Tintinnidae 5

372 246 29 1,970 123 116 135 13 0

0 0

B 12,600 509 128 32,190 1,760 43 3d2 133 23 0

25 I

rjeij a edulis veligers S

0 709 0

17 156 26 10 42 5

402 18 B

30,600 452 0

0 3,490 43 0

31 34 21 13 sivalve umboae valiger S

10 868 42 6

i 0

10 8

0 0

0 B

15,800 180 29 0

La0

)

0 31 6

0 0

Gastropod veliger S

0 523 86 0

4 18 43 8

21 48 0

B 7,960 30 10 73 4.070 114 103 103 27 26 30 Niatella spp. veliger S

5 64 0

6 v

6 0

4 0

9 0

I B

2,260 0

0 0

112 268 0

10 11 0

0 Ojehona app. Female S

563 1,920

$29 34 161 25 24v 301

'r e 164 39 B

4,540 410 27 248 132 260 257 96 52 17 I

centropages spp. coperatite S

0 0

24 0

44 811 201 1,070 510 4,010 93 B

0 0

21 315 7

109 23 268 60 Pseudocalanus spp. Female S

0 754 278 0

0 31 0

0 0

325 8

9 1,030 642 103 1,C80 1,920 663 217 56 129 16 59 I-Mesozoan S

0 0

1,140 872 30 125 5

0 0

B 0

0 0

124 349 55

5 21 0

0 0

femors 2cngicornis nale S

0 0

24 22.

0 49 12 11 5

0 0

B 0

130 9

1,370 681 199 2,070 58 79 5

0 femra long2ccrnis remale S

3 72 4

23 30 67 la 0

0 0

0 B

0 275 0

1,310 525 121 1,010 36 29 0

0 Bryczcan cyphonautes larvae S

0 0

0 1,430 360 50 0

10 0

I J

0 0

28 79 4

26 11 0

4 I

M M

M TABLE 3.2-4.

DOMINANT TAXA AND MAXIMUM DENSITIES FROM EACll SAMPLE TYPE AND PLANKTON COMP 0NENT (FROM TABLES 3.2-3, 3.2- ).

SEABROOK ECOLOGICAL SFUDIES, JULY TilROUGH DECEMBER 1977.

l HOLOPLANKTON MAXIMUM MAXIMUM DENSITY DFNSITY MICR0 ZOOPLANKTON (nO./m3)

MACR 0 ZOOPLANKTON (no./m )

3 Pseudocalanus/calanus nauplii 93,500 Calanus finnurchicus co:.n podites 187 Pseudocalanus spp. coperodite 69,800 Centropages typicus zaalt 358 Oithona spp. nauplii 19,000 Euphausid calytognaly l a rv w 193 Oithona spp. copepodites 19,700 Euphausid furcilia l a rv. Aw 125 copepod nauplii 25,300 Tortanus discaudatus nule 74 Tomora longicornis copepodites 49,700 MER0 PLANKTON bivalve veligers 16,800 cancer borealis larvae zoca 63 Mytilus edulis veltgers 30,800 Evalus pusiolus larvac 43 Hiatella spp. veligers 2,260 Carcinus maenas zoea 24 gastrolid veligers 7,960 Bryozcan cyphonautes larvae 1,430 TYCH0 PLANKTON Neomysis americana juvenile 38 l

s

22 3

TABLE 3.2-5.

ABuilDANCES (no./1000 m ) 0F f!ACR0Z00PLAi4KT0i1 TAXA (>10% ON ONE OR I

MORE COLLECTI0i1 DATES, OR 6-f10i1TH ABUNDANCE >M 0F TOTAL ABUNDAi4C2)

AT STATIONS 2, 5 AilD 6.

SEABROOK ECOLOGICAL STUDIES, JULY THROUGH DECEf1BER 1977 T

A I

T I

$aMotF naTe 0

TAXA N

7/6 7/20 a/3 8/23 9/7 10/4 11/1 12'15 12/27 I

2 18,20, 39,600 149,000 180,00C 257,00C 8,700 396 1,460 2,830 Calanus fDunarchleus cepepodite 5

21,3CC 79,200 132,0C0 142,000 174,000 12,40C eel 1,753 0

6 31,50C 124,C00 93,000 89,40c 181,000 E3,400 11,300 1,120 0

2 899 5,C80 4,48; 6,260 82,600 58,600 78,700 17,20C 3,030 centropa7es typicus female 5

1,56; 54,600 288 2,040 30,600 101,000 112,0C0 69,000 0

I 6

3,85C 4,100 12,900 32,600 21,000 566,000 215,000 54,0C0 2

1,140 5,890 305 312 41,200 26,000 70,200 11,500 472 Centrepages typicus male 5

312 35,000 288 0

15,600 33,900 92,200 35,000 0

6 865 1,870 4,460 13,100 6,450 358,000 166,000 19,800 0

I 2

193,000 139,000 738 27,900 299 1,243 5

16 11 O;naasta:ea calyptorsis 5

61,300 96,000 419 7,750 9

638 42 48 0

larvae 6

188,000 95,900 309 3,500 0

2,720 77 35 0

I 2

125,000 if,500 12,300 11,000 936 460 2

48 3

Euphaasiacea furcilia larvae 5

57,700 44,800 4.210 10,500 54 297 62 64 0

6 105,000 47,300 6,230 R,260 43 11,100 29 81 0

2 39,900 73,700 18,300 8, 0C 0 4,100 11,500 1,640 315 5,260 Tortanus discaudatus male 5

33,300 64,500 8,45C 12.200 26,90C 5,980 706 0

0 6

27,200 48,10C 6,740 4,450 10,600 4,940 0

3 96 0

2 28,200 26,900 23,100 62,100 31,700 0

0 0

0 Cancer borea21s toea 5

36,000 14,100 3,550 63,300 3,890 0

44 0

0 6

19,000 63,800 9,230 13,500 11,000 82 65 0

0 I

2 26,000 33,400 9,490 14,500 6,710 4,400 3,100 262 4,660 Tortanus diseaudatus female 5

39,900 27,500 8,800 7,200 17,000 1,860 941 0

0 6

18,200 35,600 9,890 2,010 20,400 1,470 561 0

0 I

2 6,950 42,500 11,400 38,300 6,070 106 47 8

2 rualus pustolus larvae 5

2,280 43,000 4,830 24,000 3,960 36 622 16 0

6 3,870 10,700 3,760 2,750 1,660 131 38 2

0 2

2,580 0

30$

2,090 51,800 1,190 7

0 0

Fodon spp.

5 0

0 5

0 47,000 99 1

0 0

6 1,350 0

0 3,190 59,300 12 3

0 0

2 3,700 9,210 20,000 4,940 6,680 341 7

0 1

Carcinus maenas zoea 5

1,900 6,220 7,700 4,06 0 1,950 1,090 11 2

0 6

3,100

',900 23,700 2,770 3,080 363 9

3 0

I 2

2,100 7,910 4,370 3,620 780 0

0 184 3

rseudocalanus spp. female 5

3,460 5,430 4,200 3,300 0

0 2,030 286 0

6 6,750 16,300 1,730 24,900 0

0 561 715 0

2 0

1,100 950 22,200 6,670 0

792 0

199 Metridla lucens carepodite 5

0 3,400 579 10,600 439 0

4a6 407 0

6 96 9 6,210 327 21,500 t98 437 561 0

0 2

0 0

5,420 411 13,300 1,010 56 Centropages spp. cepepodite 5

0 451 0

36) 3,310 5,260 10,300 9,990 0

6 1,450 0

0 2,C00 2,.10 3,380 4.840 1,210 0

2 88 1,360 335 40 35 4,770 4,900 104 68 Neomysis americana juvenile 5

174 320 2

2 164 1,100 427 154 C

6 0

3 13 0

2 3d,100 458 650 0

2 93 539 337 646 697 535 793

',043 22,000 i

l Sagitta elegans 5

3 347 121 1,950 194 508 215 1,700 0

I 6

177 131 178 417 39 4,910 240 1,460 0

i lI l

l l

23 I

Dominant macro-holoplankton were composed largely of copepods and euphausid larvae (Tables 3. 2-4 and 3. 2-5). Euphausid larvae and adults of Tortanus discaudatus occurred in highest densities during July and generally decreased in abundance through December.

The most abundant species collected during the six month period, Centrotages typicus adults and copepodites, occurred in highest densities from Leptember through early December. Although adults of Calanus finmarchicus were collected in only low abundances (averaged over all stations), rope-podites of this species were the second me abundant group and occurred in highest densities during August and September.

Meroplankton were dominated by gastropod and bivalve veligers, bryozoan larvae and decapod larvae (Tables 3. 2-3, 3.2-4, 3.2-5).

The micro-meroplankton, bivalve and gastropod veligers, were collected in mcderate to high abundances during July and early Septemz ar.

Bryczoan cyphonautes larvae were the only micro-meroplankton taxon which showed any depth affinity; they were more dense in near surface waters. The macro-meroplankton were dominated by decapods which were most numerous from July through September.

Although the tychoplanktonic assemblage was diverse, only one species, Neomysis americana, was collected in high densities (Tables 3.2-4 and 3.2-5).

Juvenile forms outnumbered adults; both life stages were collected in highest densities by 505 pm towed nets during October and November.

3.2.2 Discussion Organism density trends generally substantiated patterns observed in previous data.

Microzooplankton densities, which are expected to substantially exceed macrozooplankton densities and which did so in 1975-76 and 1976-77, were one to three orders of magnitude higher than for macrozooplanktcn during the July through December 1977 period. For both net and pump sampling programs in 1977, the observed seasonal abundance pattern was also generally characteristic of the same period in 1975 and 1976: densities were highest from July through September and subsequently

24 I

declined to a December minimum. An occurrence of unusually high densities of Nodiolus modiolus veligers in October 1976 caused the only deviation from this pattern.

Relative densities of holo, mero-and tychoplankton were con-sistent since 1975, although the numbers of species within meropplankton and tychoplankton increased with the intensified effort to identify decapod larvae and individual tychoplanktonic taxa.

The increased effort to identify decapod larvae and individual tychoplanktonic taxa.

The increased effort expanded the list of species identified from about 70 taxa in 1975 and 1976 to 185 taxa in 1977.

Taxa identified in 1975 as important seasonal components of the zooplankton community were designated as indicator species (NAI, 1976). These included Oithona spp., Calanus finmarchicus and Eurgte-mora herdmani all of which have historically been ubiquitous in the study area, with a surface affinity and with population maxima from late spring to early fall.

In 1977, these holoplankton taxa showed similar seasonal trends to other years, with slightly lower densities than previously observed, and no surface affinity.

In 1977 Calanus finmarchicus I

copepodites were the dominant macrozooplankter. Maximum densiti<s occurred in Augut_ and September and were comparable to previous years. Calanus finmarchicus is the dominant offshore species in the Gulf of Maine IShe rman, 1970) with copepodites abundant in the spring and summer.

Eurgtemora herdmani has exhibited a pronounced seasonality in abundance, favoring the mid-summer period.

In 1977 Eurgtemora spp. copepodite abundances were maximal in July and August, with densities slightly exceeding the previous two years.

I I

m 25 I

4.0

SUMMARY

A total of 76 phytoplankton taxa were identified from the 76 um net pumped samples and from whole water samples taken from July through December 1977.

The whole water method collected higher densities than net samples and sampled an assemblage including smaller, (<76 um) forms not sampled by the net.

Met phytoplankton reached maximum density in July, while whole water plankton were most abundant in November I

reflecting a blcom of Olisthodiscus luteus. Chlorophyll a concentration maxima coincided with the whole water density maximum. Net phytoplankton densities were low compared to 1975 and 1976, while chlorophyll a concentrations were either similar to or greater than those observed in previous years. The observed low net phytoplankton density is not believed to be representative of a decline in either overall phyto-plankton levels or in those species characterized as net phytoplankton.

I Both chlorophyll a and whole water sample results support this contention.

In the zooplankton, 185 taxa / life stages were identified from 76 pm net pumped samples (microzooplankton) and 505 pm meter net samples (macrozooplankton). Zooplankton from pump samples have consistently occurred in higher densities than from towed samples. Both components were maximal from July through September with a December minimum; in the macrozooplankton high densities continued through November due to high abundances of Centropages typicus. Numbers and species composition were similar to previous years except where influencea by program modifications.

The most notable differences were a substantial increase in overall species richness, reflecting initiation of tychoplankton and decapod larval identification to species and the inclusion of decapod larvae in species counts.

I I

I t

26 I

5.0 LITERATURE CITED Environmental Protec':i.on Agency. 1973 Biological field and laboratory I

methods for merisuring the quality of surface waters and effluents.

EPA 670/4-73-001.

1974. Chemical methods for the analysis of water and I

wastewaters. Methods development and quality assurance Res.

Lab. Manual. 298 pp.

Normandeau Associates, Inc.

1977.

Seabrook Environmental Studies, 1975-1976. Monitoring of plankton and related physical-chemical factors.

Tech. Rep. VII-5.

1978. Seabrook Environmental Studies, 1975-1977. Monitor-ing of plankton and related physical-chemical factors.

Tech. Rep.

VIII-3.

61 p.

I

Sherman, K.

1970. Seasonal and areal distribution of zooplankton in coastal waters of the Gulf of Maine, 1967 and 1968.

Strickland, J. D. H. and T.

R.

Farsons.

1972. A handbook of seawater analyses.

Fish. Res. Bd. Canada. Bul. No. 167(2nd ed.) 310 pp.

I l

(

I I

I

a a

a-.

,n

,I

I I

I APPENDICES I

I I

,I I

I l

i i

i I

I I

I

28 l

APPEflDIX TABLE 1.

TAXOt10MIC LIST OF flET APID UHOLE WATER PHYTOPLAtlKTON COLLECTED FROM JULY THROUGH DECEMBER 1977. SEABROOK ECOLOGICAL STUDIES, JULY THROUGH DECEMBER 1977.

SAMPLE TYPE Class:

Bacillarophyceae i

Order: Centrales Centrales sp.

a Biddalphia alternans b

Biddulphia aurita c

i Ceratulina bergonii b

Chaetoceros affinis a

Chaetoceros brevis a

l Chaetoceros debilis a

Chaetoceros decipiens a

Chaetoceros laciniosis a

Chaetoceros lorenzianus a

Chaetoceros sp.

a Chaetoceros teres a

Corethron hystrix b

i Coscinodiscus sp.

c Detonula confervacea a

Guinardia flaccida c

Helosira num::uloides a'

l Melosira sp.

a Isthmia nervosa a

Katodinium rotundatum b

Olisthodiscus luteus b

Olisthodiscus sp.

b Paralia sulcata c

Protocentrum nicans c

i Protocentrum redfieldi b

Prorocentrum triestinum b

Rhizosolenia alata c

i Rhizosolenia delicatula c

Rhizosolenia hebetata b

Rhizosolenia setigera b

Skeletone.rs costatum c

i Thalassiosira nordenskioldii b

Thalassiosira rotula a

Order: Pennales c

i Asterionella glacip is c

Cocconeis scutel*.um b

Cyclindrotheca J10sterium c

l Grammatophora angulosa c

Grammatophora marina a

Gyrosigma halticum

=

Gyrosigma fusciola b

l Gyrosigma/P1eurosigma s9 c

Continued

I 29 I

APPENDIX TABLE 1.

(Continued)

I SAMPLE TYPE Licmophara abbreviata c

I Licmophora flabellata c

Navicula crucigera b

Navicula sp.

c I

Nitzschia longissima b

Pennales b

Rhabdonema arcuatum a

Thalassionema nitzschioides a

I Thalassionema sp.

b Class: Dinophyceae Order: Peridiniales I

Amphidinium sp.

b Ceratium fusua c

Ceratium horridum a

Ceratium lineatum a

I Ceratium longipes c

Ceratium minutum b

Ceratium sp.

a I

Ceratium tripos c

Gyrodinium sp.

b Peridinium depressum c

Peridinium sp.

b Peridinium triquetrum b

Peridinium trocholdeum b

Order: Dinophysiales Dinophysis acuminata b

Dinophysis norvegica b

Dinophysis rotundatum b

I Class: Chlorophyceae Order: Chlorococcoles Pediastrum sp.

b Class: Chlorophyceae I

Order: Volvocales Chlamydomonas sp.

b Class: Cryptophyceae b

I Order: Cryptcmonadales Chroomonas sp.

b Class: Chrysophyceae Order: Chrysomonadales I

Dictyocha fibula b

Dictyocha speculum b

Class: Euglenophycea e I

order: Englenales Eutrep tiella sp.

b a = collected in 76 um net sample I

b = csllected in whole water sample c = collected in both 76 um net and whole water samples I

I

30 APPENDIX TABLE 2.

TAXONOMIC LIST OF HOLOPLANKTON IDENTIFIED FROM OBLIQUE 505 pm TCWS (G) AND 76 um PLANKTON PUMP SAMPLES (*), JULY THROUGH DECEMBER 1977. SEABROOK ECOLOGICAL STUDIES, Jt;LY THROUGH DECEMBER 1977.

I I

KEY:

Microcooplankton G Macrozooplankton MOLOPLANKTON PHYLUM:

PROTOZOA Subphylum:

Ciliophora Order:

Tintinnida PHYLUM:

ANNELIDA I

Class:

Polychaeta Tomopteris helgolandica G

Tomopteris spp. Larvae G

I PHYLUM:

ARTHROPODA Class:

Crustacea Subclass:

Branchiopoda l E suborder:

cladocer^

g Evadne spp.

O Evadne herdmanni G

Penilia averostris Podon spp.

C*

Podon leuckarti G

Subclass:

Ostrocoda (planktonic)

I Subclass:

Copepoda Copepoda nauplii Order:

Calanoida Acartia spp. copepodite Acartia hudsonica (=claust)

G Acartia budsonica female Acartia hudsonica male Acartia longiremis copepodite G

Acartia longirenis female

G Acartia longiremis male

G l q Aetideus arnatus copepodite C

l Anomalocera opalus G

Anomalocera opalus copepodite G

r Calanus finmarchicus copepodite d*

Calanus finmarchicus female G

Calanus finmarchicus male G

Calanus spp. copepodite I

Centropages spp. copepodite G*

Centropages hamatus fe= ale G*

lI Continued i

I 31 APPENDIX TABLE 2.

(Continued)

I Centropages hamatus make I

Centropages typicus female G*

Centropages typicus male G*

Eurgtemora spp. nauplii Eurgtemora herdmani copepodite m

Eurytemora herdmani male Eurytemora hcrdmani female I

Eurytemora herdmani ovigerous Metridia lucens copepodite G

Metridia lucens female G

Metridia lucens male

G l

Paracalanus spp. copepodite Paracalanus parvus copepodite Paracalanus parvus female I

Paracalanus parvus male Pseudocalanus spp. copepodite G*

Pseudocalanus spp. female G*

Pseudocalanus spp male G*

I Pseudc'calanus/Calanus nauplii Temora spp. copepodite Temora longicornis copepodite G*

I Temora longicornis female G*

Temora longicornis male G*

Tortanus discaudatus copepodite

G Tortanus discaudatus female

G Tortanus discaudatus male

G Tortanus discaudatus egg Order:

Harpacticoida I

Microsetella norvegica Order:

Cyclopoida Cyclopold copepodite

+

I Oithona spp. nauplii

G Oithona spp. copepodite

G Oithona spp. female

G

'I cithona spp. male

G Superorder:

Hyperiidae G

Parathemisto guadichaudi G

Superorder:

Eucarida Order:

Euphausiacea lW Cyrtopia larvae G

l Calyptopis larvae G*

(g Furcilia larvae G*

lB Thysancessa spp. cyrtopia larvae G

Thysanopoda acutifrons cyrtopia G

I Superorder:

Gamaridea Calliopius laeviusculus G

Calliopius laeviusculus ovigerous G

I Continued Unidentified (freshwater) 1arvae

I I

APPENDIX TABLE 2.

(Continued)

I Pontogenia inermis G

Pontogenia inermis ovigerous G

Rhachotropis oculata G

PHYLUM:

CHORDATA Urochordata g

PhTLUM:

CHAETOGNATHA Sagitta elegans g*

I I

33 I

APPENDIX TABLE 3.

TAXONOMIC LIST OF MER0 PLANKTON IDENTIFIED FROM OBLIQUE 505 m TOWS ( ) AND 76 m PLANKTON PUMP I

SAMPLES (*), JULY THROUGH DECEMBER 1977. SEABROOK ECOLOGICAL STUDIES, JULY THROUGH DECEMBER 1977.

I KEY:

Microzooplankton G Macrozooplankton MER0 PLANKTON PHYLUM:

CNIDARIA Class:

Hydrozoa Aglantha spp.

G Catablema vesicarum G

Euphysa aurata G

Hydrozoan medusal stage G*

Hybocodon prolifer G

Phialidium spp.

G I

Sarsia spp.

G PHYLUM:

ANNELIDA I

Class:

Polychaeta Nereis pelagica G

Polychaete egg Polychaete larvae I

Polychaete nectochaete larvae G

Procerae spp.

G I

PHYLUM:

MOLLUSCA Class:

Gastropoda Gastropoda veligers Littorina littorea eggs G*

Opisthobranchia veligers Class:

Bivalvia Anomia spp. veliger I

Bivalve st. hinge veligers Bivalve umbone veligers Ensis directus veligers I

Hiatella spp. veliger Mytilidae juvenile G

Mytilidae veliger G

Mytilus edulis veliger Placopecten magellanicus veliger G

Continued I

I

34 APPENDIX TABLE 3.

(Continued)

I I

PHYLUM:

ARTHROPODA Class:

Crustacea Order:

Harpacticoida I

Harpacticoida nauplius G

Order:

Cyclopoida Caligus elongata ovigerous G

Order:

Monstrilloida Monstrillidae G

Subclass:

Cirripedia Cirripedia nauplii G

Cirripedia cypris Hansens nauplii Subclass:

Malacostraca Superorder:

Hyperiidae G

I Hyperoche medusurum G

Superorder:

Eucarida Order:

Decapoda I

Brachyura zoea G

Calacaris templemanni G

Cancer borealis negalogs G

I Cancer borealis zoea G*

Cancer borealis stage I G

Cancer borealis stage II G

Cancer borcalis stage III G

Cancer borealis stage IV G

Cancer borealis stage V D

Carcinus maenas zoea G*

I Carcinus meenas stage III G

Caridea zoea G

Caridion gordoni Larvae G

Crangon septemspinosa zoea C*

I Crangon septemspinosa stage I G

Crangon septemspinosa stage II G*

Crangon septemspinosa stage III G

Crangon septemspinosa stage IV G

Crargon sepcenspinosa stage V Q

Crangon septemspinosa stage VI G*

,g Eualus pusiolus G

'l Homarus americanus stage I G

Pagurus spp. stage I G

Pagurus spp. stage II G

ll Pagurus spp. stage III G

E Pagurus spp. stage IV O

PHYLUM:

BRYOZOA I

Bryczoan cyphonautes larvae I

I

35 APPENDIX TABLE 4.

TAXONOMIC LIST OF TYCH0 PLANKTON IDENTIFIED FROM OBLIQUE 505 pm TOWS (G) AND 76 um PLANKTON PUMP SAMPLES (*), JULY THROUGH DECEMBER 1977. SEABROOK ECOLOGICAL STUDIES, JULY THROUGH DECEMBER 1977.

I KEY:

Microcooplankton G Macrozooplankton I

PHYLUM:

PROTOZOA Subphylum:

Sarcomastigophora Order:

Foraminiferida PHYLUM:

PLATYHELMINTHES G

PHYLUM:

R MICHOCOELA Cerabratulus sp.

G I

PHYLUM:

NEMATODA Unspecified nematcd

G I

PHYLUM:

ANNELIDA Class:

Polychaeta Order:

Phyllodocidae Goniada maculata G

Procerae G

Nepthys spp.

G Nereis sp.

O I

scalibregma inflatum G

Order:

Polynoidae Unidentified juvenile G

Order:

Cirratulidae I

Chaetozone spp.

G Order:

Terebellidae Polycirrus tenuiseta G

I Order:

Flabelligeridae Pherusa plumosa G

PHYLUM:

MOLLUSCA I

Class:

Gastropoda Subclass:

Opisthobranchia Aeolidacea O

Coryphellidae O

Class:

Bivalvia Unspecified bivalve

G

'I I

Continued I

36 APPENDIX TABLE 4.

(Continued)

PHYLUM:

ARTHROPODA I

Class:

Arachnidae Order-Acari Parasitengona a

Class:

Crustacea Subclass:

Ostracoda Unspecified benthic ostracod G

I Subclass:

Copepcla Order:

Harpacticcioa Alteutha obionga G*

Tegastidae I

Thalestris longimana Unspecified harpacticoids Zaus spinatus I

Superorder:

Peracarida Order:

Cumacea Diastylis spp.

G Diastylis oviergous G

Dirstylis sculpts G

Diastylis sculpta ovigerous G

Diastylis polita G

I Diast.ylis polita ovigerous G

Diastylis quadrispinosa G

Eudorellopsis deformis G

Eudorella pusilla G

I Lamprops quadriplicata G

Leucon americanus G

Petalosarsia declivis G

I Pseudo 1eptocuma utinot G

Pseudoleptocuma minor ovigerous G

Unspecified cumacean Q*

Order:

Isopoda I

Edotea triloba G

Chiridoten spp.

G Chiridotea tuftsi G

I Idotea spp.

G Idotea balthica G

Idotes phosphorea G

Unspecified isopod G

I Order:

Amphipod Acanthanotozoma serratum G

Aeginina longicornis G

Amphiporeia virginiana G

Corophium s99 G

Corophium spp. ovigerous G

I Corophium e:cherusicum G

Corophium bonel1i G

Corophium bonelli ovigerous G

Corophium insidiosum G

I Cymadusa compta G

Dexamine thea G

Erichthonius rubricornis G

Gacmarel1us angulosus G

Continued I

ll APPENDIX TABLE 4.

(Continued)

Gantatus spp.

G Gamnarus lawrencianus G

Ischyrocerus anguipes G

l Ischyrocerus anguipes ovigerous G

Jassa falca ta G

Jassa falcata ovigerous G

Leptocheirus pingu!.s G

l Marinogammarus stoerensis G

Monoculodes spp.

G Monoculodes tuberculatus G

l Orchomene11a pinguis G

Photis macrocoxa G

Pleustes panoplus G

Stenothoidae O

l Synchelidium americanum G

Syrrhoe crenulata G

Tiron spiniferum O

l Unciola irrorata G

Unspecified amphipod G

Unidentified Aoridae G

Order:

Mysidacea l

Erythrops erythrophthalma G

Mysis mixta male G

Mysis mixta female G

l Neomysis americana G

Neomysis americana juvenile G

Neomysis americana male G

Neomysis 9mericana female G

l Neomysis americana ovigerous G

Neomysis americana larvigerous O

Superorder:

Eucirida Order:

Decapoda Brachyura negalops G

Cancer irroratus Juvenile G

Carcinus maenus negalogs G

l Caridion gordoni post larva G

Czangon septemspinosa G

Crangon septemspinosa ovigerous G

E Crangon septemspinosa post 1arva G

Eualus pusialus Larvae G

Eualus pusiolus megalops G

l Eualus gaimardii post 1arva G

l E

Hippolytidae Q

Hyas coarctatus megalops G

Pagurus spp. glailcothoe G

l i

Continued ll 1

l

\\

38 i

i APPEllDIX TABLE 4.

(Continued)

Class:

Insect.'.

Crder:

Hemiptera I

l Family:

Corixidae Q

Bryozoan statoblast G

I l

4 1

I I

. -

ML20033A177

Text

1.0 INTRODUCTION

SUMMARY

1.0 INTRODUCTION

SUMMARY

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