ML20082C088

Ecological Studies of WOOD-BORING Bivalves in the Vicinity of the Oyster Creek Nuclear Generating Station.Final Report: September 1,1976 - December 31,1982

ML20082C088
Person / Time
Site:	Oyster Creek
Issue date:	10/31/1983
From:	Hoagland K ACADEMY OF NATURAL SCIENCES OF PHILA.
To:	NRC OFFICE OF NUCLEAR REGULATORY RESEARCH (RES)
References
CON-FIN-B-8138 NUREG-CR-3446, NUDOCS 8311210434
Download: ML20082C088 (189)

Text

NUREG/CR-3446 Ecological Studies of Wood-Boring Bivalves and Fouling Organisms in the Vicinity of the Oyster Creek Nuclear Generating Station Final Report September 1976 - December 1982 i

l Prepared by K. E. Hoagland Academy of Natural Sciences of Philadelphia US uclear Regulatory 2 2 paA2E6n84*

CR-3446 H PDR

NOTICE This report was prepared as an account of work sponsored by an agency of the United States Government. Neither the United S:ates Government nor any agency thereof, or any of their employees, makes any warranty. -xpressed or implied, or assumes any legal liability of re-spensibility for any third party's use, or the results of such use, of any information, apparatus, product or process disclosed in this report, or represents that its use by such third party would not infringe privately owned rights.

The views expressed in this report by the author are not necessarily those of the U.S. Nuclear Regulatory Commission.

Availability of Reference Materials Cited in NRC Publications Most cocuments cited in NRC publications will be available from one of the following sources:

1. The NRC Public Document Room,1717 H Street, N.W.

Washington, DC 20555

2. The NRCIGPO Sales Program, U.S. Nuclear Regulatory Commission, Washington, DC 20555

3. The National Technical Information Service, Springfield, VA 22161 Although the listing that follows represents the majority of documents cited in NRC publications, it is not intended to be exhaustive.

Referenced documents available for inspection and copying for a fee from the NRC Public Docu-ment Room include NRC correspondence and internal NRC memoranda; NRC Office of Inspection and Enforcement bulletins, circulars, information notices, inspection and investigation notices; Licensee Event Reports; vendor reports and correspondence; Commission papers; and applicant and licensee documents and correspondence.

The following documents in the NUREG series are available for purchase from the NRC/GPO Sales Program: formal NRC staff and contractor reports, NRC sponsored conference proceedings, and N RC booklets and brochures. Also available are Regulatory Guides, NRC regulations in the Code of Federal Regulations, and Nuclear Regulatory Commission Issuances.

Documents available from the National Technical information Service include NUREG series reports and technical reports prepared by other federal agencies and reports prepared by the Atomic Energy Commission, forerunner agency to the Nuclear Regulatory Cornmission.

Documents avai'able from public a.1d special technical libraries include all open literature items, such as books, journal and periodical articles, and transactions. federal Register notices, federal and state legislation, and congressional reports can usually be obtained from these libraries.

Documents such as theses, dissertations, foreign reports and translations, and non-NRC conference proceedings are available for purchase from the organization sponsoring the publication cited.

Single copies of NRC draft reports are available free upon written request to the Division of Tech-nical Information and Document Control, U.S. Nuclear Regulatory Commission, Washington, DC 20555.

Copies of industry codes and standards used in a substantive manner in the NRC regulatory process are maintained at the NRC Library, 7920 Norfolk Avenue, Bethesda, Maryland, and are available there for reference use by the public. Codes and standards are usually copyrighted and may be purchased from the originating organization or, if they are American National Standards, from the American National Standards institute.1430 Broadway, New York, NY 10018.

GPO Pnnted copy price: %.00

NUREG/CR-3446 RE Ecological Studies of Wooc-Boring Bivalves and Fouling Organisms in the Vicinity of the Oyster Creek Nuclear Generating Station Final Report September 1976 - December 1982 atoYu sh o r1

. E. H agfand c my of Na ural S ences of Philadelphia iadrlpba PA 19103 Prepared for Division of Health, Siting and Waste Management Office of Nuclear Regulatory Research U.S. Nuclear Regulatory Commission Weshington, D.C. 20665 NRC FIN B8138

PREVIOUS REPORTS Twelve reports were prepared under Contract AT(49-24)-0347 (=NRC-04 347) during three years of funding from the U.S. Nuclear Regulatory Commission, 1976-1979, under the title:

Analysis of populations of boring and fouling organisms in the vicinity of the Oyster Creek Nuclear Generating Station with discussion of rele-vant physical parameters.

Those reports with NTIS numbers are:

NUREG/CR-0223 Dec. 1, 1977-Feb. 28, 1978 NUREG/CR-0380 Mar. 1, 1978-May 31, 1978 NUREG/CR-0634 Sept. 1, 1977-Aug. 31, 1978 NUREG/CR-0812 Sept. 1, 1978-Nov. 30, 1978 NUREG/CR-0896 Dec. 1, 1978-Feb. 28, 1979 NUREG/CR-1015 Mar. 1, 1979-May 31, 1979 NUREG/CR-1209 June 1, 1979-Aug. 31, 1979 Five reports have been published in this current series under contract NRC-04-82-009:

Ecological studies of wood-boring bivalves in the vicinity of the Oyster Creek Nuclear Generating Station.

NUREG/CR-1517 Sept. 1, 1979-Feb. 28, 1980, 65 pp.

NUREG/CR-1795 March 1-May 31, 1980, 31 pp.

NUREG/CR-1855 June 1-Aug. 31, 1980, 48 pp.

NUREG/CR-1939 Vol. 1 Sept. 1, 1980-Nov. 30, 1980, 36 pp.

Vol. 2 Dec. 1, 1980-Feb. 28, 1981, 41 pp.

Vol. 3 March 1, 1981-May 31, 1981, 38 pp.

Vol. 4 June 1-Aug. 31, 1981, 44 pp.

NUREG/CR-2727 Vol. 1 Sept. 1-Nov. 30, 1981, 40 pp.

Vol. 2 December, 1981-February, 1982, 28 pp.

Vol. 3 March - May, 1982, 34 pp.

Vol. 4 June - August, 1982, 38 pp.

- - . _ . ._- - -=_.--_~. __ - __ - - - . - _ _ _ ~ .

I 1

3 ABSTRACT ,

. t

The species composition, distribution, and population dynamics of wood-boring bivalves were studied using wood test panels at 20 stations in the j vicinity of the Oyster Creek Nuclear Generating Station, Barnegat Bay, New Jersey. Physiological tolerances of three teredinid species were in-i vestigated in the laboratory and correlated with field values of tempera-

] ture, salinity, siltation, precipitation, and plant operations. The in-i teraction of boring and fouling organisms was examined.

! There is a definite correlation between the operation of the power plant and teredinid outbreaks. Increased salinity and water flow as well as temperature are responsible. After 1976, most of the damage in Oyster Creek was done by the introduced subtropical species Teredo bartschi. It can respond faster than native species to environmental w.lge. Although j Oyster Creek contributed larvae to neighboring parts of Barnegat Bay, its role as a breeding ground was limited. Some elements of the fouling com-munity may be antagonistic to shipworm growth. Fouling was increased in both biomass and species richness in Oyster Creek when compared with creek controls, but the fouling community in Oyster Creek was less stable than that in other areas. Lower salinity limits for the teredinids were

within the salinity range found in Oyster Creek but not within the range found ir. the control creeks. i I conclude that arrival of the introduced species exacerbated the wood l destruction process in Oyster Creek and also in Forked River. Shipworm control has been achieved recently as an ancillary byproduct of prolonged

shutdowns of the Oyster Creek Nuclear Generating Station. Teredo bartschi may have been eliminated in 1982.

1 t

1 I

r iii I

h l

- - - ~ , - _ , , , _ - . . --

l

SUMMARY

OF FINDINGS The purpose of this project was to determine the relationship between the operation of the Oyster Creek Nuclear Generating Station and the proli-feration of marine wood-boring organisms in Barnegat Bay, New Jersey, including creeks flowing into the bay. Changes in the fouling community were also explored, in order to see if there was a general effect on marine communities, such as shifts in species composition or decreased community stability. Of particular concern was the relative importance of Teredo bartschi in the boring community. It was thought to have been introduced to Barnegat Bay from Florida. Once causal relationships between physical environmental factors and the structure and dynamics of the boring and fouling community were identified, a qualitative model could be constructed, describing the probable results of certain envir-onmental modifications. We suggest ameliorative actions and give caveats to those engaged in power plant-related marine / estuarine alterations.

This report includes discussion of some of the data collected by our research group and others prior to the funding of this work by the Nucle-ar Regulatory Commission.

1. The mean monthly AT in Oyster Creek, compared with an average of temperatures at the northern and southern control stations, was 6.4

• C before 1976 and 4.1 C a f ter. That in Forked River was 0.9 "C I after 1976.

i

2. The salinity in Oyster Creek and Forked River was the same, within 2 /oo, and intermediate between the creek controls and the outer bay controls. It is typical of the salinity along the inner margin of Barnegat Bay. It is close to the optimal for the three teredinid inhabitants for most of the year.

3. In summer, the temperature in Oyster Creek exceeded the temperature limits for growth and normal respiration of native teredinids, but for short periods. In winter, the temperature elevation was enough to prevent mortality to some individuals of Teredo bartschi, al-though many perished.

4. Recirculation of the heated effluent into Forked River could be doc-umented on many occasions. Larvae of Teredo Lartschi and presumably other teredinids came from Oyster Creek to Forked River and to Ware-town, N.J. T. bartschi settled and matured at Waretewn twice and Forked River 3 times in the course of the study, but each time, died out.

i V i

l I

I

i l

I

5. The settlement period for teredinids in 1976-1982 was: Bankia 1 gouldi, June-early September; Teredo navalis, June-early October; T. l bartschi, early June-early November; and T. furcifera, May-early October.

6. Teredo navalis carried larvae in the gills from June (occasionally Hay) to November, while T. bartschi did so all year long. T.

bartschi's young are released as pediveligers and can immediately penetrate wood. The life cycle is shorter in Teredo bartschi than the other species. These plus other differences in the life history of T. bartschi enable it to take advantage of rapidly changing environments and to undergo rapid outbreaks.

7. The growth rate and mature size of the three species is Bankia gouldi > Teredo navalis > T. bartschi. Mortality rate was the inverse. Few T. bartschi survived past Ay ril of any year.

8. Growth was restricted by crowding, b t. *, in uncrowded panels was higher in Oyster Creek.

9. Outages of the Oyster Creek Nuclear Generating Station especially in winter and spring correspond to reduced populations of teredinids, especially Teredo bartschi. But the latter can recover quickly when the thermal effluent returns, as long as a few adults survive. No adults appeared to have survived the outage of 1982, at least in our test panels.

10. Data from a related study showed that the original introduction and subsequent bottlenecks reduced the genetic variability in Teredo bartschi.

11. The general structure of the fouling community at one place is similar from year to year, but species composition differs. Great differences in structure occur from station to station.

12. The fouling organisms Hydroides dianthus and No1gula manhattensis are inversely related in abundance to Teredo bartschi.

13. Differences in the fouling community in Oyster Creek and Forked River must be explained by differential recruitment of larvae, due to water circulation patterns instigated by the plant and by its treatment of the water entering Oyster Creek.

14. In general, salinity is a major factor in fouling community compo-sition, and temperature and siltation are important in community stability, vi

4 l

15. The temperature range for Teredo bartschi is shif ted about 4-5 'C  !

higher than that of the native species. Salinity tolerances are l similar. In Oyster Creek, the native species are stressed at the

, upper temperatures, while T. bartschi is stressed at lower temper-atures. Salinity is a stress factor only in tidal creeks.

l 16. A comparison of data from 1971-1976 with that from this report indi-cates that the shipworm outbreak was worse in early years when the AT was higher, particularly in winter.

17. The dist.ribution and abundance of Teredo bartschi follow the opera-tion pattern of the Oyster Creek Nuclear Generating Station. This

! species was responsible for the shipworm outbreaks in Oyster Creek and the mouth of Forked River after 1973, and its presence is di-1 rectly related to the power plant effluent. The history of T.

bartschi in Barnegat Bay most clearly demonstrates the effect of the power plant.

t i

1 i

vii i

e r-*r en-- -

t v e --

TABLE OF CONTENTS ABSTRACT. . . . . . . . . . . . . . . . . . . . . . . . . . . . . iii

SUMMARY

OF FINDINGS . . . . . . . . . . . . . . . . . . . . . . . v LIST OF FIGURES . . . . . . . . . . . . . . . . . . . . . . . . . xi LIST OF TABLES . . . .. . . . . . . . . . . . . . . . . . . . . xii ACKNOWLEDGMENTS . . . . . . . . . . . . . . . . . . . . . . . . . xv

1. INTRODUCTION . . . . . . . . . . . . . . . . . . . . . . . . . . I 1

2. METHODS. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 2.1 Boring and Fouling Populations. . . . . . . . . . . . 3 2.2 Physiological Ecology . . . . . . . . . . . . . . . . 13

3. PHYSICAL FACTORS . . . . . . . . . . . . . . . . . . . . . . . . 17 3.1 Temperature . . . . . . . . . . . . . . . . . . . . . 17 3.2 Salinity. . . . . . . . . . . . . . . . . . . . . . . 22 3.3 Plant Outages and Water Flow Data . . . . . . . . . . 29 3.4 Silt. . . . . . . . . . . . . . . . . . . . . . . . . 29 3.5 Weather . . . . . . . . . . . . . . . . . . . . . . . 31 3.6 Wood in Oyster Creek and Barnegat Bay . . . . . . . . 31

4. SHIPWORM POPULATIONS . . . . . . . . . . . . . . . . . . . . . . 35 4.1 Species Abundance and Distribution. . . . . . . . . . 35 4.1.1. Cumulative Panels . . . . . . . . . . . . . 35 4.1.2. Yearly Panels. . . . . . . . . . . . . . . . 42 4.2 Reproduction and Seasonal Settlement . . . . . . . . 60 4.2.1 Monthly Panels. . . . . . . . . . . . . . . 60 4.2.2 Gonad Studies . . . . . . . . . . . . . . . 75 4.2.3 Brooding. . . . . . . . . . . . . . . . . . 75 4.2.4 Plankton. . . . . . . . . . . . . . . . . . 80 4.3 Growth. . . . . . . . . . . . . . . . . . . . . . . . 82 4.4 Wood Destruction. . . . . . . . . . . . . . . . . . . 84 4.5 Wood' Penetration. . . . . . . . . . . . . . . . . . . 91 4.6 Physiological Ecology . . . . . . . . . . . . . . . . 92 ix l

I l

l

l 1

1 l

5. FOULING COMMUNITY. . . . . . . . . . . . . . . . . . . . . . . . 97 5.1 Comparison of Stations and Years. . . . . . . . . . . 97 5.2 Interaction with Boring Organisms . . . . . . . . . . 100 5.3 Individual species distribution patterns. . . . . . . 105

6. GENERAL DISCUSSION . . . . . . . . . . . . . . . . . . . . . . . 107 6.1 Interpretationn of Results (1976-1982). . . . . . . . 107 6.2 Early Physical Data (1969-1976) . . . . . . . . . . . 109 6.3 Early Shipworm Data, Barnegat Bay . . . . . . . . . . 115 6.4 Other Relevant Shipworm Studies . . . . . . . . . . . 122 6.5 A Model of Shipworm Outbreaks . . . . . . . . . . . . 123 6.5.1 Conditions for Shipworm survival and outbreaks. . . . . . . . . . . . . . . . . 123 6.5.2 Nursery Theory . . . . . . . . . . . . . . . . 125 6.5.3 Niche Dimensions and Competition . . . . . . . 126 6.5.4 Introduced Species: Generalizations . . . . . 130 6.6 The Boring and Fouling Community. . . . . . . . . . . 131

7. CONCLUSIONS . .... . . . . . . . . . . . . . . . . . . . . . . 135

8. PREDICTIONS AND RECOMMENDATIONS . . . . . . . . . . . . . . . . . 137 REFERENCES. .. ... . . . . . . . . . . . . . . . . . . . . . . 139 APPENDICES. . . . . . . . . . . . . . . . . . . . . . . . . . . . 147 A. List of Stations . . . . . . . . . . . . . . . . . . . 147 B. Data Collected Sept.-Nov., 1982. . . . . . . . . . . . 150 C. List of Species found in Barnegat Bay. . . . . . . . . 164 DISTRIBUTION LIST . . . . . . . . . . . . . . . . . . . . . . . . 171 l

X l

1 i

l l

LIST OF FIGURES Page

1. Overview of Barnegat Bay and its location in New Jersey. . . . 6

2. Locations of Stations 1-13 . . . . . . . . . . . . . . . .. . 7

3. Locations of Stations 14-17. . . . .. . . . . . . . . . . . . 8

4. Locations of Stations 18 and 19 on Long Beach Island . . . . . 9

5. Averages of monthly temperatures in Oyster Creek, Forked River, &nd Bay controls. 1976-1982 . . . . . . . . . 18

6. Averages of monthly salinities in Oyster Creek, Creek Controls, and Forked River . . . . . . . . . . . . . . 25

7. Seasonal relationship of gonad ash-free dry weight to total ash-free dry weight. Bankia gouldi. . . . . . .. . . 77

8. Analysis of factors affecting shipworms in their environment . 124

9. Ecological and niche differences between Teredinid species . . 127 xi l

1 I

l I

LIST OF TABUIS Page

1. Panel Series with Dates of Submergence. . . . . . . . . . . . . 4

2. Stations and Replications Used in the Course of this Study. . . . . . . . . . . . . . . . . . . . . 5 .

3. Average Monthly AT's between Oyster Creek - Forked River, Forked River - Bay Controls, and Oyster Creek - Bay Controls. 20

4. Average Monthly Difference in Salinity between Oystcr Creek -

Creek Controls, Oyster Creek - Bay Controls, and Oyster Creek - Forked River. . . . . . . . . . . . . . . . . . . . . 23

5. Outages of the Oyster Creek Nuclear Generating Station December, 1975 through August, 1982 . . . . . . . . . . . . . 27

6. Oyster Creek Nuclear Generating Station Combined Circulation and Dilution Water Flow . . . . . . . . . . . . . . . . . . . 28 J

7. Qualitative Silt Data . . . . . . . . . . . . . . . . . . . . . 30

8. Summary of Temperature and Precipitation Patterns: Northern, Central, and Coastal N.J. . . . .. . . . . . . . . . . . . . 32

9. Piles in Oyster Creek . . . . . . . . . . . . . . . . . . . . . 34

10. Relative Frequencies of Occurence: Cumulative Panels. . . . . . 36

11. Average Number of Shipworms per Panel in Oyster Creek, Cumulative Panels Submerged in May of Each Year . . . . . . . 38

12. Cumulative Panel Survival Rates . . . . . . . . . . . . . . . . 39

13. ANOVA of Total Number of Shipworme, Annual Panels . . . . . . . 43

14. ANOVA of Number of Living Specimens, Annual Panels, Fall Months. Stations grouped according to Hydrography . . . 61

15. ANOVA of Number of Living Specimens, Annual Panels, Fall Months. Stations grouped according to Geography. . . . . . . 62 xii l

l l

l L

_ . m-.- - . - -

i i

16. Average Number of Colonists (Alive & Dead) on Monthly Panels (all species, averaged within stations) . . . . . . . . . . . 70

17. Average Number of Colonists (Alive & Dead) on Monthly Panels (all species, averaged within stations and over stations within station group, using stations 1, 4, 5, 8, 10, 11, .

12, & 14) . . ........................ 73  !

i 18. Ratio of Ash-Free Gonad Weight: Total Tissue Weight, Bankia gouldi, Combined Yearly and Cumulative Panels . . . . . . . . 76 l 19. Fraction of Adult Specimens Found with Larvae in the Brood Pouch . . . . ................... . . . . . 78 i

20. Teredinid Larvae from Plankton Samples taken 0-1 and

2-3 m from Bulkheads. .................... 81

21. Growth Data on Shipworms from Oyster Creek vs. other Stations . 83

22. Nested Analysis of Variance of 2/3 Power of Percent Wood Weight Loss in Annual Panels . ................... 85

23. Nested Analysis of Variance of 2/3 Power of Percent Wood Weight Loss in Cumulative Panels . . . . . . . . . . . . . . . . . . 87 i

j 24. Nested Analysis of Variance of 2/3 Power of Percent Weight i

Loss, Cumulative Panels Submerged in May at Stations 1, 4, 5, 8, 10, 11, 12, and 14. . . . . . . . . . . . . . . . . . . 89

25. Settlement Patterns, Teredinid Species. . . . . . . . . . . . . 91

26. Physical Tolerances of Teredinids from Oyster Creek and Barnegat Bay. ........................ 93

27. Annual Minimum Salinity Records, by Station . . . . . . . . . . 95

28. Annual Maximum and Minimum Temperature, by Station. . . . . . . 96

29. Total Overlap by Station Group for Averaged Percent Cover, Attached Fouling, Annual Panels Collected in August. . . . . 98

30. Total Overlap by Station Group for Averaged Percent Cover, Attached Fouling, Cumulative Panels Collected in August . . . 99

31. Total Overlap by Station Group for Averaged Percent Cover, Attached Fouling, Cumulative Panels Collected in November . . 101 xiii I

._. ._m . _ . _ . _ _ . . - . _ . _ . _ .

4 Total Overlap of Averaged Percent Cover Comparing Years by 32.

Station Group . . . . . . . . . . . .. ... . .. . .. . . 102

33. Correlation Coefficients for Percent Cover of Selected Fouling Organisms with Teredinid Species Abundance. . .. .... . . 104

34. Settlement of Some Major Fouling Organisms. . ... . ... . . 106

35. Monthly Temperatures, in *C, 1971-1976. .. .. . . . ... . . 111

36. Monthly Salinities, in */.., 1971-1976. . . .. .. . . .. . . 113

37. Shipworm Attack in Cumulative Panels, 1971-1976 . ..... . . 116

38. Colonization of Monthly Panels, 1971-1976 . . . . .. ... .. 120

39. Major Ecological Differences, Teredinidae in Barnegat Bay . . . 129 A1 Temperature Profiles in *C, September - November, 1982. ... . 152 A2 Salinity Profiles in */ ., September - November, 1982 . .. . . 153 1

A3 Numbers of Living Shipworms in Cumulative Panels Submerged

, May 9, 1982 . . . . . . . . . . . . . . . . . .. .... . . 154 A4 Numbers of Living Shipworms plus Empty Tubes, Cumulative Panels Submerged May 9, 1982. . . . . .. . . .. . ... . . 155

! A5 Percentage of Specimens that were Alive when Collected, Cumulative Panels . . . . . . . . . . . ... ... .. . . . 156 A6 Length Ranges of Shipworms, in mm, Cumulative Panels Submerged May 9, 1982 . . . . . . . . . . . . . . .. . .. ... .. . 157 A7 Number of Shipworms in Yearly Panels Removed September 8,1982. 158 i

A8 Length Ranges of Shipworms, in mm, Yearly Panels Removed Sept. 8, 1982 . . . . . . . . . . . . .. . . .. . . .. . . 159 A9 Percentage of Living Teredo navalis Carrying Larvae in the Gills . . . . . . . . . . . . . . . .. . . . . .. .. . . . 160 t

A10 New Settlement of Fouling Organisms, October 8 - November 8, 1982. . . . . . . . . . . . . . . . . ... . .. .... .. 163 xiv-1 l

l l

ACKNOWLEDGMENTS We thank the many residents of Oyster Creek who have cooperated in our field work. Particular thanks go to the Baumgardt family, W. and R. Crisman, W. and V. IIolzman, W. Campbell, S. Cottrell, T. Gilmore, C. Kochman, and E. Sheridan, who have watched over our equipment. They and many others have allowed us the use of their property. We thank M. Roche and others of the Environmental Branch at Jersey Central Power and Light Company (G.P.U.) for their cooperation in providing plant operations data. Technical assistance has been provided by many persons between 1976 and 1982, including M. Rochester, L. Crocket, J. McKinley, J. Selman, J. Ilarms, J. Flynn, B. Tanzosh, T. liickey, E. B5hlke, P. Abrahamsen, D. Dragotta, K. Pidcock, R. Hermansen, J. Schaeffer, and N. Karnow. John Hendrickson assisted in statistical analysis. Many ex-perts assisted in identifying fouling organisms. These include W. Saul (fish), F. Drouet and R. Fralick (algae), E. L. Bousfield (amphipods),

M. Rice (miscellaneous invertebrates), J. Carlson, T. Loi and H. ten Hove (polychaetes), J. Chapman and R. Gore (crustaceans), W. Lee (sponges), E.

A. Caine (Capre11idae) S. Wohlgemuth (pycnogonids), and R. Robertson (gastropods). This manuscript reviews early, unpublished data collected by R. D. Turner and her associates, 1971-1974. It also refers to data on the population genetics of shipworms, obtained under a Fleischmann Foun-dation grant to the Wetlands Institute and Lehigh University. This manuscript was reviewed by P. Ilayes and G. M. Davis.

xv

ECOLOGICAL STUDIES OF WOOD-BORING BIVALVES AND FOULING ORGANISMS IN THE VICINITY OF THE OYSTER CREEK NUCLEAR GENERATING STATION' September 1, 1976 - December 31, 1982 FINAL REPORT

1. INTRODUCTION The Oyster Creek Nuclear Generating Station between Oyster Creek and Forked River, New Jersey (Fig. 1) began operation in December, 1969. It is operated by the Jersey Central Power and Light Company (J.C.P. & L).

It uses Forked River as a source of cooling water and Oyster Creek as a discharge canal fcr its once-through cooling system. When the station is pumping water, the water flows from Barnegat Bay upstream into the South Branch of Forked River and finally through a dredged canal to the station (Young & Frame, 1976). The warm water effluent is discharged via a canal into Oyster Creek (Fig. 2). Up to 3 dilution pumps are used to bring water directly from the intake canal to mix with heated discharge water, in order to reduce the temperature of the effluent. This cooling system has increased the salinity of the water in both creeks to that of adja-cent parts of Barnegat Bay. Characteristics of Barnegat Bay have been reviewed elsewhere (Kennish & Olsson, 1975).

Docking facilities have been in Oyster Creek since 1944, but not until the summer of 1971 did the property owners become aware of large scale teredinid (shipworm) damage to their docks, piles, bulkheads, and wooden boats in the creek. Because the creek formerly had been of low salinity,

". . . freshwater to about 2,500 feet downstream of U.S. Route 9 . ." .

(Directorate of Licensing, U.S. AEC, 1973), it had been thought safe for untreated pilings despite the fact that shipworm attacks have occurred in Barnegat Bay itself (Nelson, 1922). Under new conditions suspected to have been caused by the Generating Station cooling system, the Oyster Creek marinas were providing massive amounts of wood for shipworm infes-tation.

Dr. Ruth Turner began research into the Oyster Creek shipeorm outbreak in summer, 1971, at the request of 3 marina owners. Early work (Turner, 1974a-c) indicated that the generating station was responsible for the shipworm outbreak by (. cawing larvae into Forked River and Oyster Creek, and by increasing the salinity and temperature. Summaries of these find-l l

1.

iags were sent to the Atomic Energy Commission. The author of this re port (Dr. Hoagland) joined the project in 1975. The shipworm study was expanded to include more stations in May, 1976, with funds from Lehigh University, and in September, 1976, the U.S. Nuclear Regulatory Commis-sion (NRC) provided funding for the study.

Early in the course of the study, we hypothesized that the temperature and salinity regime in Oyster Creek could cause early and/or extended re-production of shipworms. Increased growth rater and hence amount of dam-age to wooden structures were also suspected. There was a possibility that Oyster Creek would serve as a breeding ground for shipworms that could migrate into Barnegat Bay. We were also concerned about the risk of introduced species becoming established in Oyster Creek. Could intro-duced species acclimate to local conditions and if so, did they compete with native species? Finally, we hypothesized that the fouling community interacts with (competes with, preys upon) marine borers. Hence, we were interested in studying the species composition and density of fouling organisms relative to shipworms.

In the years 1974-1976, J.C.P. & L. made changes in their Oyster Creek operations at the request of the NRC. The Oyster Creek marinas were pur-chased, untreated pilings, docks, and trash wood were removed, and the temperature of the effluent was reduced through increased pumping of un-heated dilution water. An attempt was made to stabilize creek banks, in order to reduce siltation in Oyster Creek. Our earlier reports to the NRC (p. ii) summarize the raw data on physical parameters, marine borers, and fouling organisms since mid-1976. Data prior to the changes, 1971-1976, are in unpublished monthly reports, available from the author.

One long-range goal of the study is to understand the reasons behind teredinid outbreaks, and to discover possibilities for prediction, pre-vention, and as a last resort, control of outbreaks. I comment on the siting and operation of plants producing waste heat, with res;ard to po-tential teredinid attacks and fouling problems. The report is divided into sections that consider data on physical environmental parameters (particularly temperature, salinity, and plant operations), teredinid population parameters, teredinid reproduction and settlement, teredinid growth, wood destruction, wood penetration patterns, teredinid physiolog-ical tolerance, and finally, the fouling community. Each section con-tains a discussion, but a full general discussion follows the last data section.

2

_ . .l 1

s l

2. METHODS '

2.1 Boring and Fouling Populations Untreated straight-grain white pine panels, 2 x 9 x 21 cm, were used to collect populations of boring and fouling organisms. The panels were weighed, soaked in artificial seawater of 25 /oo for two weeks, attached to, aluminum racks, and set into the water vertically, resting about 15 cm above the water-sediment interface. All panels were aligned similarly with respect to currents and depth. They were placed along creek or bay shoreline off docks and bulkheads, 0.8 to 2.0 m deep, i Data were collected from 3 types of panels: (1) Monthly panels. One panel was removed each month and replaced with one that, in turn, was re-moved the following month. These panels recorded the monthly settlement and initial growth of the boring and fouling organisms. (2) Cumulative panels. Starting with the submergence of a set of 12 panels in early May, one panel was removed each month to record cumulative progress (growth, reproductive potential) of the boring and fouling organisms.

(3) Yearly panels. We replaced the cumulative panel at the time it was removed each month. After our first year of operation, the rack con-tained a full set of 12 panels. In the second year that began on May 5, 1977, these were removed in sequence. Thus each had been in the water 12 months, with a different starting time. We placed a second rack at each ,

site at the start of the second year, to continue the original cumulative panel experiment. (The start of our year corresponds to the beginning of i the breeding season of the shipworms). In the third year, beginning May, 1978, and in subsequent years, the yearly panels were replicated at 5 stations. Yearly panels show the age and size structure, population den-sity, and species composition of a standard-aged community of shipworms and fouling organisms. The panels allowed us to check the reproduction of a larger sample of borers than would be obtainable from cumulative panels. Table 1 lists the panel series with dates of submergence.

A total of 20 stations were established - in Barnegat Bay and its tidal creeks during the course of our study. As changes occurred, such as re-moval of docks and dredging in Oyster Creek and at station 15, and silt-ing at station 6, and as our funding leve.1 and study plan changed, we altered the location .of some stations, and the number of stations in use.

A core of 8 stations were used throughout our funded study and the pre-ceding study, began by Dr. Ruth Turner, in 1971. Table 2 details the stations used in the course of the study, and any replication of panels.

Replication of all types of panels at each station would have been desir-able for statistical purposes. But space considerations at most stations precluded such replication. Deployment of any more panels would have i

3 l

l

Table 1 Panel Series witt Dates of Submergence Monthly Submerged the first week of every month and removed 28-33 days later. 10/71 - 11/82. Some minor irregularities in years 1971-1975.

Cumulative Submerged in spring of each year prior to the settlement period for shipworms. Dates for the years prior to 1974 are available in the reports of R. D. Turner. Some irreg-ularities occurred. Series in 1971-1973 were begun in August - September.

7/1/74 5/5/75 4/27/76 5/27/77 6/6/78 5/5/79 5/3/80 5/7/81 5/9/82 Yearly Submerged the first week of every month and removed one year later. First yearly panels submerged 4/27/76 and removed 5/5/77.

f i

4 l

l l-l l

Table 2 Stations and Replications Used in the Course of This Study Stationi Date Started Date Discontinued Panel Series Replicated Prior to 1982 1982 1 10/71 11/82 c, y c, y 2 4/76 9/79 3 10/71 11/82 y c 4 4/76 11/82 c, y c 5 4/76 11/82 e 6 5/75 6/79 7 9/75 10/79 8 8/74 11/82 e c 9 5/77 10/79 10 10/71 11/82 c 11 10/71 11/82 c, y c, y 12 10/71 11/82 c 13 5/77 11/79 14 1/75 11/82 y c 15 5/75 6/78 16 4/76 6/78 17 4/76 6/79 18 5/77 10/79 19 5/77 10/79 20 5/78 11/79 I

See Appendix A for description of Station localities.

c = cumulative series; y = yearly series 4

5-

s Figure 1. Overview of Barnegat Bay and its Location in New Jersey A8 BURY PARK e (L1 r13 i Cf Lu r-

~3 ,

,i Aj V 3 '

,,l f, HOLLY PARK . BARNEGAT

/ /

/ l BAY

/ / l h j , FORKED RIVER: .

i i

h,,'

WARETOWN .

BARNt'. GAT

• f NEMT

- _ _ , LIGHT MANAHAWKIN *  ?

L

's 7,

O s

4 g,p , ,

o xM io

• ATLANTIC CITY A

l 6

I i

Figure 2. Locations of Stations 1-13 4.- . 'e..,. 3 l

. , s- ,;,K .

W W.'*] l te0LLY hum il . , jy; y -

la

&s . ,' Ii,'k'. .-

th. u. '.

y ggtpA CRIEN

• 4,.hy ;f Ib,' '

iKM 9  ?? *.?

% / A b.L' , 4. .,

I < . ,

I

. ' ' .. 3 STOUY's cRtEx #

t_ .t, -

p "us e y n .-

-~ - _a A pogggo M ER e.

1. : ' . < . . .. -  :

. . t :: ,

. . 1;'- 2.ig.;.p.,.V

.; 'ge. r . r*,.vl't<Q...

- g..'a s.; , '

• /.' . , .. ^>- , q. s, .i . ,: ,.. s .e . ,,

lh:l, y;.

'. 0! ', .

,' , ji,:)h ~

k

+ S' 4

,.}? , .l{h$ ,

U . . .

'k oyster CREEK j . 7 Mg',<.

,. '.' .,n , .* '.} ,$p , 'd? $ . .:?:

i ,i.

' . . Oft,s : ,,'ft(I' ~ Y ,5)[.

c

.{f.

.g'

' ['.f: s,  :. . r I

' e'.,jf,hfI 6 (., g

• 3 . '.A I * ..

- ,\,'fd 6 ,- !

P, N4 k. ,*

f.c,

• .4D. , u.,-

. :n.z l

'2. . c <

., i M ' .- .J,- 2 "3 N .:

'*  :. .5 4

j'y l

d*gi,'.'

. -9.qd,..

,- i..-

.,w.'... .s,..

4; J.., . ,. , . a s;. h. ,,

1.. ' ., ' ,, . ,, ,e ,', -

l .. -

? ,--

'?". #b ,U . ,g' ,

T.13 lil6.7.h, .3f'd . . ,e-e 1:,b en,e, ,

+ ' J ' ;, * . ;'

,-3),' C2 8g

_ - u . -8.,* .

I 1

1 7

Figure 3. Locations of Stations 14-17 CySTER CREtt.

E H J.

s'}

w aerown caten

'b p

. -: ..y ,s

!.h lh

\

M

-- .e . n d l

l

~kd p-d O KM i

'o t ,

87 l MANAMAWKIN BAY l

l u

8

l ys .

e BARN 66AT LIONT 6

O MN g

\

Figure 4. Locations of Stations 18 and 19 on Long Beach Island 9

caused interference among them (creation of micro-current patterns, crea- ,

i tion of the archipelago effect on colonization rates, etc.). Figures 1-4  !

j show the station locations. The 1976 research plan called for groups of I stations similar in temperature and salinity, based on preliminary samp-

! ling in 1975-1976, so that a variance estimate could be constructed for the data. These groups were as follows:

stations 1, 2, 15, 16, 17 I Inshore bay controls  :

l Outer bay (island) controls  : stations 18, 19 Tidal creek controls  : stations 3, 7, 20 S. Branch, Forked River  : stations 4, 5, 6, 9 Oyster Creek  : stations 10, 11, 12, 13

, Edge of thermal effluent  : stations 8, 14 i (Creek mouths) i

Subsequent data collection showed that these groups were internally vari-able. In particular, water circulation and pollution caused differences 1 among the stations 18 and 19 chosen to be replicates. Restricted water circulation caused reduced settlement and survival of shipworms and other I

organisms at stations 10 and 19. Extremely rapid flow prevented most settlement at stations 9 and 13 in the intake and discharge canals, re-

+

spectively. These two stations were eliminated from most analyses. Sta-i tion 2 had higher water flow than other inshore bay controls, but was l retained within its group for statistical analyses. Stations 8 and 14 l proved hydrographically to be essentially like stations 4 and 15, respec-1 tively, and were grouped with them for some analyses as described in the 1 text. Thus, several groupings of stations for statistical analysis were used as statistical analysis proceeded.

The above groups were the station groups used to analyze the effects of

temperature and salinity on the boring and fouling community. They are

based on physical conditions as they existed at the time the data were

, collected. The groups represent the closest replication of station phys-

, ical conditions, and with the creek controls, the best approximation to pre-operational conditions in Oyster Creek that we could achieve. The groupings allow one to assess the relative boring and fouling problem in the inner and outer Barnegat Bay, Oyster Creek, Forked River, and tidal creek controls similar to Oyster Creek's stations 11 and 12, and to Forked River's stations 5 and 6. A difficulty is an inability to assess the shipworm damage at the various creek mouths, in particular at the mouths of Oyster Creek and Forked River, compared to the levels of damage that might have existed had the thermal effluent not existed. There are i insufficient replicates to form an Oyster Creek mouth or a Forked River i mouth grouping. In interpreting the data based on the station groups l above, one must realize that we are seeing the average conditions in each

group. If there is a difference between creek controls and Oyster Creek, 1

i 10 l

for example, that represents an inferred difference at stations 11 and 12 in Oyster Creek before, relative to after the Creek was altered. We can be less certain about station 10 near the mouth of Oyster Creek.

A second grouping of stations reflecting geographical location and ignor-ing the known hydrographical data was also used to analyze the shipworm data. In this scheme, the groups were:

Oyster Creek  : 11, 12 Forked River  : 5, 6 Creek Controls  : 3, 7, 20 South Barnegat Bay  : 15, 16, 17 North Barnegat Bay  : 1, 2 (creek mouths)

Creek Mouths  : 4, 8, 14 (affected by effluent)

Outer Bay  : 18, 19 The disadvantage of this finer subdivision is that there is less chance of finding statistical significance with such small groups. Two stations had to be eliminated. However, two potentially interesting comparisons could be made: 1) upper Creek controls versus only the upper stations in Oyster Creek and Forked River; 2) the mouth areas of Oyster Creek and Forked River versus mouth areas of creeks to the north, and portions of the bay.

In the field, temperature and salinity were taken using hand-held instru-ments at a depth of 30 cm each month at each station. The time of day was also recorded. Beginning December 12, 1976, the water temperature was monitored via continuous recorders at four stations, #1 (control), 5 (Forked River), 11 (Oyster Creek), and 14 (edge of effluent). Beginning in November, 1977, salinity was monitored continuously at the same sta-tions. The continuously-recorded data can be used to correct for time of day in the monthly temperature and salinity data. However, poor perform ,

ance of the continuously-recording salinometers limited the usefulness of the continuous salinity data.

During much of the period of study, the amount of silt on the panels was estimated as trace, light, moderate, or heavy by two persons in the field, independently. Turbidity in the water column was measured in 1976-1977 by using a turbidimeter and also by drying and weighing the sample. Water samples were taken at a depth of 0.4 m with a sampler that could be filled and closed when the proper depth was reached.

While at each field station, observations were made for damage to wooden structures caused by boring organisms. In summer and fall months of 1980-1982, plankton samples were taken via a small plankton net dragged 11

1 I

a 1

in the vicinity of the panels and at distances of approximately 0-3 '

meters away from the wooden structures of the station. Any special occurrences likely to affect the boring and fouling community, such as ice formation, dredging, or use of wood treatments in the area, were

! noted.  ;

In May, 1980, white pine 3 x 7 cm stakes 90 cm long were submerged at

stations 1, 4, 8, 10, 11, and 14. Three inntical stakes were driven j into the mud substrate against the bulkhead at each station, at a slight

! angle and such that the stakes extended above the water line. Several of 7

the stakes were lost (particularly those at station 1). The purposes of the experiment were to test the idea that shipworms settle preferentially at the mudline, and to see if the different species have the same settle-ment preferences. The stations were chosen to maximize the probability of obtaining large sets of all species. One and then two stakes from l each station were removed after 4 and 16 months, respectively, and marked i as to the orientation of each surface with respect to currents. Mudlines i

and waterlines were also marked. The posts were x-rayed and measurements  ;

were taken of positions of boreholes, length and direction of growth of

burrows. Each individual borer was identified to species.

i The fouling community on wood panels and racks was observed in the field.

Using a hand lens, the structures were examined and the organisms listed i in rough rank order of abundance. Abundance was considered as the amount of surface area covered. Both attached and mobile organisms were re-corded. Organisms on monthly, cumulative, and yearly panels were listed separately. Identifications were made to species level whenever possi-ble, but for hydroids, some algae, and some bryozoa, in particular, species could not be determined in the field. The field data were to

give a pattern for the dominant life forms on the panels.

e During 1977-1979, the panels were washed in the field and the water preserved with 4% formalin. The wash water was returned to the labora-tory where the loose organisms that had been associated with the fouling community (mostly polychaetes, amphipods, and gastropods) were identi-fied.

The panels themselves were wrapped in damp newspaper, kept cool, and

, returned to the laboratory. Between 1976 and 1979, the fouling organisms present on each side of each panel were recorded quantitatively, using the point analysis technique of Suth'erland (1974). Using.a. dissecting microscope and a plastic sheet with 100 points chosen by a random number 4 system, a technician identified the species located at'each point. The percent cover by each species was calculated. Samples of the various

species, and unidentified material, were saved for positive identifi-l 12 l

l l

~ . . _ _ _ _ _ _ _ _ . _ - . - - _ _ - - _ - - - _ - - _ _ _ _ -

- - . - . - . - _ ,_ - - - - - _ - - _ - - - _ . _ - - - - ~ ~

J 2

i cation by the senior investigator. In addition to using published keys

! and reference papers (e.g. Bousfield, 1973; Fraser, 1944; Gosner, 1971; McCain, 1968; Pilsbry, 1916; Smith, 1964; Taylor, 1969), specimens were 3

sent to experts in the various taxonomic groups. These persons are listed in the acknowledgements.

, The fouling was removed and the wood was x-rayed in order to have a j record of shipworm damage and location in the wood. We determined the j number and size of all shipworms, the percent living and the species composition (Turner, 1966) by dissection of the wood to remove the j shipworms. Size was measured as the length of the relaxed animal outside its burrow. Each specimen of Teredo was examined for the presence of larvae in the brood chamber of the gills.

l Once a panel was dissected, the calcium carbonate burrow linings were removed manually, and the residue dissolved using dilute HC1. The weight I

of the remaining wood chips was recorded after the chips were dried at

60 C to constant weight. By comparing pre- and post-submergence j weights, a record of the percentage of wood destroyed by marine borers was obtained.

4

)

During 1977-1979, the gonadal material was removed from each shipworm and i

dried at 60* C overnight, separately from the remainder of the animal.

j Dry weights were obtained for gonad and somatic tissues. Then the ,

i material was ashed at 475* C for 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> and ash-free weights calculated.

i

Specimens of both boring and fouling organisms were preserved and curated into the collection of the Academy of Natural Sciences of Philadelphia.

To accompany our own data, we asked the environmental division of Jersey Central Power and Light Co. to supply us with data on the operation of the Oyster Creek Nuclear Generating Station. These data included plant outage periods and circulation and dilution flow, as well as chlorination and any unusual events such as fish kills, dredging activity and releases of any toxic chemicals. Th3 data on chlorination and other chemicals was not sufficiently detailed on a day-to-day basis to allow correlation with boring and fouling organisms. Local residents provided us information on amounts of treated and untreated wood placed in Oyster Creek and Forked .

j River over the past 15 years or so.

1 2.2 Physiological Ecology l

^

Extra panels were deployed each spring at stations 1, 4, 5, 8, 11, 12, 14, and 18 between 1979-1982 in order to obtain teredinids for physio- i logical studies. These -panels were retrieved after sufficient time to i

13

.. - - - _ _ - - - ~ _ . _ -, - - _ - _-. . _- . ..

l l

I 4 become infested. They were scraped to remove fouling and placed in holding tanks of 22-24 /oo salinity and a temperature of 24 1 3* C, close 1 to natural spring / summer conditions. Larvae released by the two Teredo species were collected and reared to various stages, then used in tem-perature and salinity tolerance experiments. In order to rear the lar-vae, cultures of the algae Nonochrysis lutherl and Isochrysis galbana were maintained as described by Pringsheim (1964) and Guillard (pers.

j comm.). The "f/2" medium was used. The procedures for culturing ship-worm larvae were those of Culliney, Boyle, and Turner (1975) and Turner and Johnson (1969).

It was possible to obtain pure cultures of Teredo navalis from panels l

taken from station 18, while some of the panels from stations 11 and 12 contained only T. bartschi. Preliminary experiments revealed no detec-tible physiological differences between specimens of the two native shipworm species collected in the thermal effluent and those collected

elsewhere. Most of the experimental T. navalis came from station 18, l while most of the Bankia gouldi came from Stations 1, 8, and 14. All T.

! bartschi came from Oyster Creek (Stations 11 and 12). Due to its lack of a long-te rm planktonic larval stage, it was possible to maintain suc-ceeding generations of T. bartschi in the laboratory tanks without mani-

- pulation (e.g., special feeding or isolation) of the larvae. T. bartschi adults could even survive and reproduce in tanks of p-filtered seawater l

without supplemental feeding.

j A series of temperature and salinity tolerance tests were conducted, some

{ short term and some lasting several months. They were performed on Teredo navalis, T. bartschi, and B. gouldi, Details on the design of individual experiments can be found in our quarterly reports. Basically,

]

behavioral changes of the animals were used to indicate temperature and

salinity stress. Withdrawal or abnormal relaxation of siphons indicated l suboptimal conditions for adults. Activity of adults could also be monitored quantitatively as the amount of frass produced during wood-boring. Pre-metamorphosed juveniles were categorized by several types of

behavior

swimming, crawling, probing the wood, beginning to bore, i closed on the bottom, or swollen and inactive on the bottom. The latter two were indicative of suboptimal conditions, if they were observed with.

! greater frequency than in controls. At least ten individuals were i studied per experimental condition, and most experiments were replicated.

l A behavioral c.hange by at least half of the test individuals was con-sidered significant. Controls were maintained for the experiments at 22 l 1 2 /oo, so that deviations from the natural patterns of activity could

! be measured. Of course, mortality and growth could also be used to assess tesiperature and salinity tolerances of - both adults and juveniles

( and were in some experiments.

t 14 1

i

l 1

! The following experiments were performed:

1. ypper salinity tolerance: gradual raising of salinity until stress

, in over half the individuals was observed, holding temperature con-l stant at 24 1 3* C. (Adult: all species. Juvenile: T. navalis

- and T. bartschi pediveligers.)

l 2. Lower salinity tolerance: gradual lowering of salinity until stress and mortality were observed, holding temperature constant at 24* C.

i (Adult: all species. Juvenile: T. navalis, and T. bartschi pediveligers; T. navalis veligers.)

{

i 3. Salinity: prolonged maintenance of adults, all species, at 25, 22, 12, 9, 6, and 3*/oo. Filtering behavior, mortality, growth, and frass production were recorded.

4. Salinity change: Salinity was raised and lowered > 10*/oo.

Pediveligers were observed for behavioral changes (T. bartschi) .

5. ypper temperature tolerance: gradual raising of the temperature at 23 /oo salinity until stress and mortality were observed. (Adult:

all species. Juvenile: T. navalis, T. bartschi, pediveligers; T.

navalis veligers).

6. Lower temperature tolerance: gradual reduction of the temperature at 23 /oo salinity, until stress and mortality were observed.

(Adult: all species. Juvenile: T. navalis, T. bartschi, pedive-ligers).

7. Winter survival: Maintenance of adults of all species at ambient winter temperatures in an outdoor water table. Observance of fil ,

tering behavior and survival. (= lower temperature tolerance).

8. Temperature-salinity synergism; optimal spawning conditions: Main-i tenance of young metamorphosed individuals at all combinations of

, 10, 20, 30" C and 6, 14, 22*/o over 3 months. Two panels each with j about 30 individuals were maintained at each condition. Frass and fecal material was weighed weekly. In addition, weekly records were kept of the presence of newly-released larvae. At the conclusion of the experiments, the panels were x-rayed and the growth of the specimens determined. (Teredo bartschi newly metamorphosed).

9. Wood preference: Behavior of Teredo bartschi pediveligers when given new wood, wood previously in the field for several months and wood containing adult shipworms.

15

10. Silt: effect of silt loading on filtration activity of adults, all species.

l I

l 16 l

l

3. PHYSICAL FACTORS 3.1 Temperature Figure 5 illustrates the average monthly temperatures in Oyster Creek (stations 10-13), Forked River and Forked River Beach (stations 4, 5, 6,

9) and in the Barnegat Bay controls (stations 1, 2, 15, 16, and 17). The strong seasonal variation and the effects of the effluent when the gener-ating station was operating are obvious. The AT values for the same data i set were calculated as the difference between the average monthly temper-~

atures in Oyster Creek and Forked River, those in Forked River and Barne-gat Bay, and the sum of these differences, equal to the AT in Oyster Creek vs. Barnegat Bay (Table 3). The average temperature in creek controls was similar to that of the bay controls.

The AT in Oyster Creek vs. Barnegat Bay (and the creek controls) was generally on the order of 2-6 *C, averaging 4.1 *C overall. The AT in Forked River was often absent but once ranged as high as 4 *C. It aver-aged 0.9 *C. These AT's were averaged over several stations along a mild l gradient, both in Oyster Creek and Forked River. Hence, the average values are less than at the tops of the gradients, station 13 in Oyster Creek and station 4 near the mouth of Forked River. Since the Oyster Creek Nuclear Generating Station began operating two dilution pumps in early 1976, the AT has been cut nearly in half. Prior to 1976, it was of ten in the range of 6-10 "C (Table 35).

Stations 8 and 14 could not be fit into any group, nor did they form a homogeneous group as far as thermal influence was concerned, so they are -

omitted from tite statistical analysis. Information about the AT's at these stations is in our quarterly reports. A positive AT at these sta-l tions occurred at different times but at neither station did it exceed 4

• C; it was usually <2 "C.

Superimposed on the seasonal fluctuations, the AT in Oyster Creek extends the potential season for growth and reproduction of shipworms and other marine organisms by about one month in fall and in spring. Bars on the y-axis of-Figure 5 delimit reproductive activity for the native species of shipworms. The interaction of shipworm physiological limitations with these physical factors is analyzed later in this report (sections 4.6 and 6). Irregularities in the temperature curve for the bay controls (e.g. ,

November warmer than October, 1977) are due to missing data for some stations, i

l 17 l

Figure 5 Averagen of monthly temperatures in Oyster Creek, Forked River, and Bay Controls. 1976-1982. Bars represent limits for LEGEND:

reproduction, native species.

A Oyster Creek 32 O Forked River O Bay Controls 30--

28--

26-24--

22--

3 20-

~

18-W --

0- 16-- j p ..

14--

00 w 12--

g ..

2 10 W ..

H 08 .

06--

04-W i a a a i i i i i i a i a e i i a 4 a a i a i e i a i i i i i i i e a. > > 0 zee E > sO a. H >02mE s m o o w <,sa. w <2 <o.2 < 3 3 mOOw<w< E > z, _a O a. H >0 zee E > z. e n. H

< e o z o ' < eOzo,t 2 < o. 4 ,<mO,2,aaw0 2o,w2<2 ow<w<o< a,a,<mo aw0 1976 1977 1978 1979

61 TEMPERATURE (*C) l I O O O O

o ob o o a a = *

• u m u u u a o A N M e a o u e e 2 i f f t f i 1 f i a t 1 1 t o u &

1 1 I e i f 1 1 1 1 1 I t t i t a e1 Io I mi t t i e

DEC '

-JAN-e a FEB-M A R- --

APR- ~

~

M AY-JUN-JUL- 's AUG- '

SEP-

- ~ ~

O C T-NOV-DEC~

-a - J A N -:

e a FEB-M A R- 2 e

APR- E M AY-

.v.

N JUN- n O

JUL - E AUG-SEP- _-

) 5

a.

O C T-NOV-DEC-

-JAN- -

e a FES-m M AR-APR- ~ . ..

~ - -

MAP JUN- UODE JUL-

,N.2,=

AuG- ogio O" 4 SEP- gom O C T- oo%

~

2 NOV-W e-

t Table 3 Average Monthly AT's between Oyster Creek-Forked River, Forked River-Bay Controls, and Oyster Creek-Bay Controls Plant Oyster C.- Forked R.- Oyster C.-

Year Month off Forked River Bay Contr. Bay Contr.

1976 8 3.07 1.83 4.90 9 5.53 0.64 6.17 10 4.67 1.46 6.13 11 2.07 2.27 4.34 12 2.00 2.38 4.38 1977 1 3.27 0.57 3.84 2 4.83 -0.11 4.72:

3 3.70 0.65 4.35 4 2.93 2.58 5.51 5 * -0.83 0.81 -0.02 6 * -4.08 no data 1.45 7

• 1.20 0.14 1.34 8 3.83 -0.67 3.16 9 3.00 -0.25 2.75 10 4.97 0.66 5.63 11 4.00 -1.55 2.45 12 3.87 0.69 4.56 1978 1 4.77 -1.16 3.61 2 3.33 -0.17 3.16 3 5.50 -1.68 3.82 4 3.40 -2.11 1.29

$ 4.17 1.58 5.75 6 4.71 0.25 4.96 7 2.27 0.54 2.81 8 3.51 1.11 4.62 9 4.68 -1.43 3.25 10

• 1.20 -1.80 -0.60 11 * -0.41 1.11 0.70 12

• 0.57 0.38 0.95 1979 1 5.36 -0.08 5.28 2 3.87 0.46 4.33 3 2.30 1.45 3.75 4 no data no data no data 5

• 0.63 -1.28 -0.65 6 2.68 1.49 4.17 7 2.38 4.42 6.80 8 1.09 2.23. 3.32 9 1.49 3.53 5.02 10 6.75 0.00 6.75 11 2.33 0.67 3.00 12 2.33 3.67 6.00 1980 1

• 1.00 0.00 1.00 2

• 1.33 -1.33 -0.00 3 * -0.33 1.67 1.34 4 * -1.33 1.33 0.00 5 * -1.67 0.67 -1.00 20

Table 3, cont.

Average Monthly AT's between Oyster Creek-Forked River, Forked River-Bay Controls, and Oyster Creek-Bay Controls Plant Oyster C.- Forked R.- Oyster C.-

Year Month off Forked River Bay Contr. Bay Contr.

1980 6 * -2.00 0.67 -1.33 7 * -0.67 1.33 0.66 8 2.33 0.67 3.00 9 2.00 3.00 5.00 10 3.33 2.00 5.33 11 2.00 2.33 4.33 12 2.00 0.33 2.33 1981 1 0.67 4.00 4.67 2 2.00 0.00 2.00 3 3.67 -0.33 3.34 4 4.00 -0.67 3.33 5 * -0.67 0.00 -0.67 6 3.00 0.00 3.00 7

• 0.67 -1.00 -0.33 8 1.00 2.00 3.00 9

• 0.67 0.67 1.34 10

• 0.67 0.33 1.00 11 3.67 -0.67 3.00 12 4.00 1.00 5.00 1982 1 * -0.33 -0.67 -1.00 2

• 0.33 -0.33 0.00 3

• 1.00 0.33 1.33 4 * -0.33 1.33 1.00 5 3.33 -0.33 3.00 6 3.33 -0.33 3.00 7 3.00 1.00 4.00 8 2.33 1.67 4.00 9 3.33 -0.33 3.00 10 2.00 1.67 3.67 11 2.33 0.67 3.00 l

l

• Note: When the plant war off, in most cases some circulation pumps remained operating. See Table 6.

21

3.2 Salinity The monthly-recorded salinities in each station group were averaged and the difference between Oyster Creek and the creek controls (stations 3, 7, 10), bay controls, and Forked River were calculated. Table 4 presents these differentials; average salinities themselves are in Figure 6.

Oyster Creek and Forked River stations had uniform salinity and all were similar to the bay controls but greatly exceeded the salinity of creek controls. On the average, the salinity in Oyster Creek was an insignifi-cant 1.4*/oo lower (11*/oo) than in Forked River. Although statistically insignificant, the difference could be due to the fresh waters of Oyster Creek itself and of the South Branch of Forked River, which mix with the bay water pumped up the South Branch of Forked River to the generating station. The average differential between Oyster Creek and Barnegat Bay was +0.2 1 2.4 /oo , which is also not significant using a t-test, given accuracy of measurement and the large standard deviation.

The similarity of salinity in Oyster Creek, Forked River, and Barnegat Bay persisted even during most outages of the generating station (Table 5). For example, in April-August, 1977, and January-July, 1980, salinity differentials were similar to those at times when the station was ope-rating. Water pumping (Table 6) was reduced by about half during most of the outage periods. Within-station group variance in salinity was also very low. Revising station groups as discussed in the methods did not affect results.

On figure 6 is indicated the lower salinity survivorship limit for ship-worms, discussed in greater detail in section 4.6. The elevated salinity in Forked River and Oyster Creek contributed greatly to the potential for

, chipworm infestation in these areas, compared with the creek controls.

Annual fluctuations in salinity are normally great in Barnegat Bay, but are even greater in tidal creeks such as Stout's Creek, Cedar Creek, and the middle branch of Forked River. The minimum salinity in these areas is frequently too low for shipworms. Shipworms may 2.tvade these tidal creeks periodically, but cannot survive there permanently.

The highest salinity recorded in Barnegat Bay was 33*/oo on Long Beach Island, at stations 18 and 19. Upper salinities never approached the levels that present shipworms with physiological stress. Diurnal salin- ,

ity fluctuation of ~2-3*/ o was common, especially in the upper few cm of l the water column at all stations, but it was not as great as that found in many natural shipworm habitats such as the Florida mangroves. Because of the daily fluctuations, the difference seen in Table 4 and Figure 6 should be viewed as meaningful outside a range of i2 /oo.

22 i

I

l Table 4 Average Monthly Difference in Salinity between Oyster Creek-Creek Controls, Oyster Creek-Bay Controls, and Oyster Creek-Forked River Salinity Difference Year Month OC-CC OC-BC OC-FR 1976 8 11.5 -0.7 0.4 9 5.4 0.5 0.3 10 8.1 0.2 -0.9 11 4.2 1.1 0.0 12 10.3 4.7 0.7 1977 1 5.2 1.3 -0.3 2 15.3 2.7 0.1 3 3.3 -1.2 -1.2 4 6.6 -1.4 -1.5 5 8.1 -0.3 -0.6 6 3.3 -2.5 -3.2 7 5.7 -1.6 0.2 8 3.0 -1.5 -1.0 9 7.5 0.1 - 1. 7.

10 3.1- -1.8 -0.1 11 0.1 -4.7 -3.2 12 1.9 -1.3 -0.7 1978 1 8.7 -3.0 -0.5 2 -

1.2 -0.3 3 11.7 -0.7 0.0 4 4.9 0.6 0.1 5 16.0 2.9 4.5 6 7.7 -0.5 0.2 7 11.7 -1.8 -0.7 8 12.6 -0.9 -2.0 9 8.1 0.1 -3.0 10 6.0 -2.1 0.3 11 4.5 -1.7 -4.0 12 10.2 -2.2 -3.6 1979 1 7.2 0.4 0.0 2 8.2 2.0 -2.1 i 3 8.3 -2.9 -6.1 4 -

2.7 -3.0-5 9.1 0.1 -3.2 l 6- 13.2 1.2 0.1 7 .11.9 1.7 -0.4  :

8 12.0 2.6 -2.3 9 12.7 1.8 -1.8 10 12.7 -0.2 '- 3.2 11 4.3 -2.0 -2.2 12 2.8 -1.2 -2.7.

'1980 1 -

-3.8 -7.1 2 -

-4.2 -0.5

'3 3.7 0.7 --0.3

.23

1

! Table 4, cont.

Average Monthly Difference in Salinity between Oyster Creek-Creek Controls, Oyster Creek-Bay Controls, and Oyster Creek-Forked River-Salinity Difference

-Year Month OC-CC. OC-BC OC-FR 1980 4 9.3 0. ,7 - -1.8 5 12.0 0.? -4 0 1 6 3.1 0.0 -2.9 7 2.7 -1.7 -0.6 8 5.0 3.3 -1.5 9 6.0 1.0 -2.0 10 0.3 0.3 -1.7 11 5.0 1.7' 2.0 12 2.7 0.7 0.2 1981 1 -

5.3 -0.7 2 -

1.5 -1.7 3 3.0 0.3 -1.0 4 1.7 -1.0 -2.3 5 3.3 -4.3 -5.2 6 5.2 0.8 -2.6 7 13.7 0.3 -2.0 8 6.0 2.0 -0.5 9 8.0 -0.5 -2.0 4

10 7.3 0.3 -0.3 11 3.7 1.3 -0.3 12 2.0 3.7 -1.5 1982 1 -5.7 1.2 -2.8 2 18.0 8.0 0.0 3 5.3 ' -1.7 -3.4 4 5.0 0.5 -3.5 5 4.3 0.3 ,-1.9 6 5.7 -0.3 -1.1 7 9.0 1.0 -0.5 1 8 6.8 -0.3- -2,2-9 6.7 -0.7 -0.8 10 7.3 0.0- -2.7 11- 4.7 -0.'7 0.7 i

i a

24 1

i i

r l ,

• E -T C O

• • 3

-PES nE8n -GUA

...new a -LUJ

!"Ae -NUJ

@OyO -YAM Q>00 -RPA

-RAM *

-BEF $

--N AJ .

a

-CED g

-VON

..5 -TCO E ;s '.

305 -PES g

• S -GUA r2- ~ -LUJ nlI - NUJ

[ ," ** -YAM 21%

n=c

-RPA e x

-RAM e n

"87

-BEF *.

o2(m

- - N AJ-

-mS.

-CED in ". a "o

- -VON E%= -TCO

.~07 -PES 4~, -GUA E*%n 1* O

-LUJ

!50 m

- NUJ

-YAM

'17,

. -l; 3

- RP A

• SP E -RAM

• 4EQ h -BEF $

T -- N AJ .

, +

-CED

-VON

-TCO

-PES a

-GUA N,

,,.,iI,,iiI. , , . , , , ,, ., ,..l

, . , . .i. . .

,,,,t . .. .

I > > e i o e o e o e o a< n n a a

)%( YTINIL A S 35

95 S A LINITY (%)

. . m u u o e o e o a o

., ,. . .t ., , ,, ,il ... l .Ii , , i I . . ,,

• NO V-

e DEC-

, - J AN-E FEB-O '

MAR-AY JUN-JUL-AUG-SEP-O C T-NOV-DEC-

,-JANa ,

E FEB-

• {

MAR--  %

APR-  ?

M A Y- p a

JUN - ".

3 JUL- F  %

AUG- "

SEP-O C T-NOV-DEC-

. -JAN-e e FEE- u-

" MAR- -G APR-M A Y-OO>F JUN- o,oo JUL - e2 E AUG- e

" w% 9 SEP- @: lp o, 3 -,

O C T- 72*

O m y NOV- .-

i

Table 5 Outages of the Oyster Creek Nuclear Generating Station December, 1975 through August, 1982 Dates Number of Days 1975 Dec. 27, 1975 - Mar. 11, 1976 74*

1976 July 28 - July 31. 3 1977 April 23 - Aug. 4. 103 October 22 - October 23 1 November 14 - November 15 1 December 3 - December 4 1 1978 June 14 - June 16 2 Sept. 4 - Sept. 5 1 Sept. 16 - Dec. 8 83 Dec. 13 - Dec. 18 5 1979 Jan. 15 - Jan. 19 4 Feb. 6 - Feb. 7 1 March 26 - April 8 13 May 2 - May 31 29 Sept. 7 - Sept. 8 1 Nov. 23 - Nov. 26 3 1980 Jan. 5 - July 19 195*

Sept. 18 - Sept. 22 4 November 22 - November 30 8 1981 March 12 - 16 4 March 28 - 31 -3 April 19 - May 28 39 June 27 - June 30 3 August 15 - August 31 16 Sept. 1 - Oct. 19 48 Oct. 31 - Nov. I 1 1982 Dec. 10 - April 15 126*

May 24 - May 27 3-June 4 - June 5 1 August 15 - August 28 13 Total 789 (32% of total. time)

• Covers critical winter /early spring period.

27

I Table 6 Oyster Creek Nuclear Generating Station Combined Circulation and Dilution Water Flow Sept. 1975 - Aug. 1962 In Liters x 10 7 , Average per Day Year Month Water Flow Year Month Water Flow '

1975 9 287.00 1979 5 334.83 10 376.49 6 525.15 11 405.44 7 532.72 12 387.92 8 533.45 1976 1 262.63 9 450.66 2 259.07 10 497.30 3 391.62 11 511.27 4 491.41 12 532.22 5 400.38 1980 1 294.40 6 473.95 2 279.26 7 499.46 3 273.87 8 511.90 4 233.56 9 461.26 5 288.66 10 454.17 6 211.76 11 523.39 7 380.47 12 501.80 8 506.96 1977 1 339.57 9 419.32 2 413.71 10 477.61 3 507.39 11 458.55 4 467.85 12 524.41 5 171.56 1981 1 539.62 6 139.44 2 512.05 7 160.48 3 468.19 8 498.16 4 394.98 9 453.28 5 286.76 10 466.24 6 480.86 11 515.23 7 524.47 12 513.52 8 453.37 1978 1 513.92 9 248.14 2 501.72 10 412.83 3 517.50 11 533.56 4 518.03 12 307.14 5 469.64 1982 1 245.38 6 501.05 2 210.99 7 521.71 3 82.07 8 522.87 4 337.83 9 311.30 5 395.32 10 162.48 6 455.40 11 209.80 7 533.28 l 12 ^439.80 8 439.75-1979 1 487'96 2 520.56 l 3 468.73 4 461.60 28

The overall pattern of salinity in Barnegat Bay shows considerable yearly va ria tion. There was a lower salinity range in late 1977 continuing through 1978, but a dry period in 1979-1980 increased the salinity. The yearly cycle is for salinity to be highest in late summer (August).

In the general discussion in this report (section 6), both the tempera-ture and salinity data presented here will be compared with data obtained in years prior to 1976.

i

, 3.3 Plant Outages and Water Flow Data Table 5 summarizes the outages of the Oyster Creek Nuclear Generating Station over the period of December, 1975 - August, 1982. Outages from 1970 - 1975 are given in Hoagland & Crocket, 1978, p. 12 (NUREG/CR-0634).  ;

These dates are of critical importance in analysing data on distribution

! and population dynamics of boring and fouling organisms. The major outages will be referred to frequently in this report. Although sche-j duled outages for refueling occurred, most of these were prolonged due to maintenance problems as detailed in reports made available to me from JCP&L, the NRC, and as announced in the public press. Unscheduled out-ages also occurred. In all, there were 789 days between December, 1975 and August, 1982 when the station was not operating. This is 32% of the total time. An outage longer than 45 days occurred about every 13 months. Between 1970 and December 1975, the plant was down 484 days, or 22% of the time.

Table 6 presents water flow data for the generating station. Circulation and dilution flow are combined, giving the total average daily flow in j Oyster Creek that would affect settlement and feeding of boring and foul-

) ing organisms, except for a proportionally small amount of water entering

the portion of the creek below the plant from natural sources. Values

are usually lower during outages (Table 5), for example, from January to July, 1980 (Table 6). Dilution pumps were used to reduce the AT in Oys-j ter Creek. Such pumping was increased after 1975. This was to accommo-date the federal and state limits on AT and dissolved oxygen. After 1977, discharge requirements were even more stringent--the discharge was not to cause a AT larger than 4 F between September and May, and 2' F during the summer months (Scolinick, 1975, Federal Permit to Discharge).

(

l 3.4 Silt The dredging of intake and discharge canals in Forked River and Oyster Creek, followed by pumping of large volumes of water and maintenance dredging, caused erosion and siltation problems in both water systems.

'29 p - w gm__,w gy., g_e -, _. - - m__._.

In fact, the Draf t Environmental Statement written prior to operation of the generating station admitted that silting was expected (U.S.A.E.C.,

1973). Later reports (U.S.A.E.C. Docket #50-219, 1974) admitted problems that would come from increased pumping to reduce AT.

Silt can smother boring and fouling organisms. Except after the dredging of Oyster Creek in March, 1979, we found no evidence that boring orga-nisms were being adversely affected by silt. In April and May of that year, anoxic mud covered the panels in Oyster Creek killing all orga-nisms.

Rapid water flow can prevent settlement, but such a problem rarely occurs along bulkheads and finger docks where microenvironments with reduced velocity exist. We found an impoverished boring and fouling community presumably due to high velocity only at stations 9 and 13, where panels were suspended from cement blocks in the currents of the constricted portions of the intake and discharge canals, respectively.

Siltation was recorded qualitatively on panels as trace, light, heavy, etc. For some months of the study, quantitative data were also taken (see Methods). The raw data are presented in our quarterly reports and summarized in Hoagland, Turner & Rochester (1977). There was a tendency for siltation to be heavier in Oyster Creek than at some control sta-tions, but due to high siltation at stations 3, 6 and 17, the data were not statistically significant when Oyster Creek was compared with all other station groups. Variation within groups and even within stations was very high.

Table 7 compares siltation in Oyster Creek (stations 10, 11, 12) and other tidal creeks (stations 3, 7, 20), relative to operation of the generating station.

Table 7 Qualitative Silt Data, Oyster Creek vs. Creek Control Averages, Computed for each Month. 2 x 2 Contingency Table.

Plant Operation On Off I Oyster Creek > Creek Controls 11 5 16 Creek Controls > Oyster Creek 4 1 5 15 6 21 30

1 While there is no significant correlation of siltation with the generat-ing station being on or off, Oyster Creek does exceed the creek controls ,

in siltation in 16 out of 21 months for which data are available for all '

stations. It is important to remember that the generating station con-Linues to pump significant amounts of water even when the nuclear reactor itself is down. Therefore, the effect of the station on silt burden should be continuous. The data do show a trend of an increased silt burden in Oyster Creek compared with the control creeks: Cedar Creek, Stouts' Creek, and the middle branch of Forked River.

3.5 Weather -

Analysis of other shipworm outbreaks such as the Barnegat Bay and San Francisco incidents in the 1920's (Nelson, 1922, 1923; Kofoid, 1921; Kofoid and Miller, 1923, 1927) suggested that drought could cause ship-worm outbreaks by increasing the salinity of bay and tidal creek waters.

l I investigated the possibility that the 1970-1980 shipworm attack in Oyster Creek and Forked River could be correlated with regional precipi-tation.

Table 8 combines the data previously given in our quarterly reports.

Recognizing that there would be a slight lag between weather itself and its effect on boring organisms, there is still no correlation between i

area temperature and precipitation patterns, as reflected by deviation from normal, and shipworm distribution and abundance (Tables 10-17). Nor were correlations found between weather and occurrence of other boring and fouling organisms. First of all, the shipworm outbreaks in 1980-1982 were due almost entirely to one species, Teredo bartschi (Table 11; see also our quarterly reports, p. ii). It was restricted to Oyster Creek and Forked River, whereas climatic factors would have affected the entire

area. Secondly, the peaks in abundance of T. bartschi (and total Teredi-nidae) do not correspond to any significant period of drought. There was

! no prolonged severe drought in the immediate area of Oyster Creek during' this period, yet shipworm damage was high in late 1980 and late 1981.

There was a reported drought in the spring and summer of 1980 (Hoagland &

Crocket, 1980, NUREG/CR-1855). During this period, the generating sta-tion was not operating and there was a dramatic drop in shipworm infesta-tion.

3.6 Wood in Oyster Creek and Barnegat Bay Historically, there has been considerable use of wood, both treated and untreated, in Barnegat Bay. Bulkheads protect property from erosion, and marinas with proj ecting docks are numerot.s. There are also a large number of older wooden boats used for both fishing and recreation. While 31

Table 8 Summary of Temperature and Precipitation Patterns Northern, Central and Coastal N.J.

Deviation from Normal Year

• Month Temperature (*F) Precipitation (In.)

1980 9 +1.7 -1.7 10 -3.8 +1.1 11 -3.1 -0.7 12 -3.0 -2.8 1981 1 -7.1 -2.6 2 +3.7 +1.4 3 -1.5 +2.4 4 +2.0 +0.5 5 0.0 +0.8 6 +0.6 +1.0 7 +1.1 -0.9 8 -1.0 -2.0 9 -1.0 0.0 10 -4.7 +0.7 11 -1.0 -2.3 12 -0.8 +0.6 1982 1 -7.7 +1.3 2 +1.0 -0.4 3 -1.0 -1.6 4 -1.0 +1.1 5 +1.0 +2.9 6 +3.6 +5.1 7 -0.1 -0.8

• Data before September, 1980, were not available for this report. In 1980, a drought was general in the New York-New Jersey-Pennsylvania area, calling attention to the need for the above data.

32

creosote-treated wood and even plastic-wrapped piles have been used to construct most of the docks and bulkheads in the bay itself, untreated cedar wood was used for years to construct many docks in the small creeks flowing into the bay. Creeks with untreated wood include Cedar, Stout's, Forked River, and Oyster Creek, among others. Cedar wood has some natural resistence to shipworm attack, but it can sustain heavy damage when the wood has been in the water for several years and when settlement of wood borers is heavy.

After the outbreak of shipworms in Oyster Creek and the mouth of Forked River in 1971, much decaying wood had to be removed and replaced with new, treated wood. In 1975, Jersey Central Power and Light purchased the 4 marinas along Oyster Creek and from November 1975, to May 1976, worked to remove docks and old pilings. Some of the old pilings broke off above j the mudline and were not completely removed. Since there were also pri-vate homes along the south side of Oyster Creek, much untreated wood re-mained in Oyster Creek. Not all individual property owners were able to replace all their wooden structures. In April, 1976, resident W. Crisman calculated the amount of untreated wood remaining in the creek. His re-sults appear in Table 9. He found that about 44% of the untreated piles, and 37% of the total piles in Oyster Creek, had been removed. In addi-tion, there was trash wood, that is, dead wood entering the creek fr'em a 2-acre stand of cedar trees partially in the water along the creek.

In 1979, Jersey Central Power and Light sold " shipworm easements" to 26 residents living on Dock Road along Oyster Creek. The money so obtained was used to replace docks and bulkheads. Although I cannot estimate the percentage of untreated wood removed at this time, it was considerable in the vicinity of our station 12. I do not believe that easements were sold as far down Oyster Creek as our station 10, but this information is unavailable to me.

There remains some untreated wood. Also, high temperatures and rapid water flow act to leach protective chemicals out of treated wood. Unless creosote is applied at high pressure, even treated wood may fail to with-stand heavy borer attack (McQuire, 1971).

33

Table 9 I

Piles in Oyster Creek Survey April 17, 1976

. MARINAS UNTREATED PILES TREATED PILES TOTAL PILES Sands Point Marina 536 Rules Boat Yard 600 192 Briarwood 680 Oyster Creek 432 2248 (44%) 192 2440 LAGOONS 1 751 72 2 785 121 3 376- 292 4 329 74-i UPPER CREEK 556 229 2797 (55%) 788 3585 TOTAL 5045 980 6025 Removed by JCP&L Jan, Feb, March 1976. Untreated only. 2248 37%.

Remaining Piles 3777 63%

i t

l t

34

- --e , ,

4. SHIPWORM POPULATIONS 4.1 Species Abundance and Distribution 4.1.1 Cumulative Panels Four species of shipworms were found in Oyster Creek and the surrounding portions of Barnegat Bay during the years 1971-1982. Between 1971 and 1973, only Bankia gouldi (Bartsch) and .Teredo navalis Linnaeus, both native to New Jersey waters, were found. However, in 1974, the tropi-cal-subtropical species Teredo bartschi Clapp and Teredo furcifera von Martens were introduced into Oyster Creek and Forked River Beach and survived for several years.

Frequencies of occurrences (percent of panels from a station group which contained a given species) were calculated for each of the four species in each of the 6 original station groups (p. 3) for each year of sampl-ing. Data from the cumulative panels are presented here; analysis of yearly panels would yielded similar results. A species was recorded as present even if it was only represented by specimens dead when collected.

A problem existed in the allocation of dead specimens of Teredo without pallets to one of the 4 possible species, especially if no living speci-mens were found on the same panel. There could be a bias if, for exam-plc, all dead Teredo in Oyster Creek and Forked River were assigned to T.

bartschi and all dead Teredo elsewhere were assigned to T. navalis.

Often, the size of the dead individuals' burrows and the pattern of set-Llement on the panel, in comparison with that of other panels collected in the same and subsequent months, could be used to make a probable iden-tification. For example, numerous clustered small, narrow burrows'in a July panel were most probably T. bartschi, whereas a few isolated burrows in a November panel were most likely T. navalis, especially if T. navalis settled on other nearby panels at the same time. In some cases (espe-cially in Forked River), no species assignment could be made.

Table 10 illustrates the differences in occurence patterns of the four i teredinids. Bankia gouldi was widespread in Barnegat Bay and Forked River in the first 4 years, while Teredo navalis had a slight edge in frequency of occurrence in the last 2-3 years. T. navalis dominated the island stations. The creek controls had few shipworms, those few being nearly all B. gouldi. Oyster Creek had the most complex shipworm fauna, with high presence of T. bartschi as well as the native species. -Both Forked River and Oyster Creek had all 4 species for long periods of time.

The creek mouth stations were variable from year to year but contained all of the species, s 35 I

Table 10 Frequencies of Occurrence: Cumulative Panels (Dashes indicate no station)

A. Bankia gouldi Station Groups

• Year Bay Forked R. Oyster C. Creek Island Creek Mouths 1976 0.842 1.000 0.933 0.333 --

1.00 1977 0.492 0.886 0.763 0.500 0.048 0.71 1978 0.816 0.949 0.516 0.000 0.222 1.00 1979 1.000 1.000 0.750 0.000 0.333 1.00 1980 0.636 0.821 0.682 0.000 --

0.82 1981 0.741 0.519 0.163 0.091 --

0.54 1982 0.400 0.500 0.129 0.000 --

0.35 B. T. navalis Year Bay Forked R. Oyster C. Creek Island Creek Mouths 1976 0.368 0.382 0.000 0.000 --

0.67 1977 0.190 0.409 0.079 0.000 0.762 0.21 1978 0.500 0.436 0.118 0.000 0.833 0.52 1979 0.955 1.000 0.708 0.000 0.833 1.00 1980 0.818 0.714 0.409 0.091 --

0.82 1981 0.963 0.923 0.419 0.000 --

0.85 1982 0.500 0.967 0.355 0.000 --

0.60 C. T. bartschi Year Bay Forked R. Oyster C. Creek Island Creek Mouths 1976 0.000 0.000 0.000 0.000 --

0.00 1977 0.000 0.000 0.184 0.000 0.000 0.00 1978 0.000 0.256 1.000 0.000 0.111 0.38 1979 0.091 0.333 1.000 0.000 .0.000 0.45 1980 0.000 0.143 0.227 0.000 --

0.24 1981 0.000 0.038 0.674 0.000 --

0.04 1982 0.000 0.000 0.000 0.000 --

0.00 D. T. furcifera fear Bay Forked R. Oyster C. Creek Island- Creek Mouths 1976 0.018 0.294 0.100 0.000 0.000 0.28 1977 0.048 0.159 0.105 0.000 0.048 0.04 1978 0.000 0.000 0.030 0.000 0.000 0.00 1979-1982 0.000 0.000 0.000 0.000 0.000 0.00 l I

• As given on page 3, Methods. '

36 d

Breeding populations of Teredo furcifera disappeared completely after 1978; their appearance in the bay and on Long Beach Island was limited and spotty in 1976-1977. T. bartschi occurred primarily in Oyster Creek,

! but expanded into the bay on several occasions. It invaded the Waretown Creek area in 1975 and 1979, and was found sporadically in Forked River in 1974-75, and in 1978-1981. Neither of the warm-water species ever i occurred at the creek control stations.

t i In summary, Bankia gouldi was common at bay and creek stations while Teredo navalis tended to be more offshore. The introduced species were both restricted to the area influenced by the generating station, at least in terms of breeding populations. These introductions are more fully discussed in two published papers (Hoagland & Turner, 1980; Hoag-land, 1983. However, it is clear that there is a correlation between operation of the generating station (Table 5) and presence of these species. Both species declined sharply over the period from late 1975-1977, when the power plant underwent prolonged spring shutdowns. Raw species counts are detailed in our quarterly reports for the years 1976-1977. While T. furcifera continued to fade out, T. bartschi underwent an outbreak in 1978-79 when there was no prolonged outage in spring (Table 11). It spread incrementally from Oyster Creek (late 1977) to the gouth of Oyster Creek (mid 1978) to the mouth of Forked River (fall, 1978) to inner portions of Forked River (Feb., 1979) and finally the middle branch (Aug., 1979). Then it contracted again, with the plant outage in 1980. Another recovery occurred in late 1980 and 1981, but the species appeared to be eliminated at least from our sampling areas af ter the 1982 winter-spring outages (Table 11). The overall distribution of T. bartschi corresponded exactly to the geographical limits of the ther-mal effluent, from Waretown to Forked River (Figure 2).

Survival rates within months on cumulative panels are presented for the three common species in Table 12. The survival rates are broken down for 3 station groups--based . on temperature and salinity data: bay controls, Oyster Creek, and Forked River--when the species was present. A dash in-dicates that no panels in a station group recorded a particular species in a particular month, or that no samples were taken. The latter was the l

case from December to May in 1982-83. There were too few shipworms found in the creek control group for meaningful analysis.

Raw survival rates were used despite logical inconsistencies that arise from sampling variation inherent in cumulative panels sampled destruc-tively. One could have adjusted the raw values by pooling adjacent vio-lators (Barlow et al., 1972), but these adjusted rates would not be mean-l ingful for Teredo spp. The record of the many individuals of Teredo that.

die very young tends to be lost as the exposed panel erodes at the sur-face, thus minimizing mortality rates for later months. A . synthetic 37 i

Table 11 Average Number of Shipworms per Panel in Oyster Creek, Cumulative Panels Submerged in May of Each Year (Alive only)

Date Removed T. bartschi B. gouldi T. navalis Major Station Outages 1972 Oct. 0 7 1 May 1 - June 20 Nov. 0 8 1 1973 Oct. 0 21 0 April 14 - June 4 Nov. 0 14 0 Sept. 8 - Oct. 5 1974 Oct.* >500 10 1 April 13 - June 29 Nov.* >500 >10 0 1975 Oct.* >500 >20 0 Feb. 4 Feb. 29#

Nov.* no panel March 29 May 26#

1976 Oct. 0 3 0 Dec. 27, 1975 -

Nov. 0 4 0 March 11, 1976#

1977 Oct. 0 3 0 April 23 - Aug. 4#

Nov. 5 3 0 1978 Sept. 625 2 0 Sept. 16 - Dec. 8 Oct. 480 2 0 Nov. 439 1 0 1979 Sept. 640 4 1 May 2 - May 31 Oct. 1,000 3 1 Nov. 400 1 2 a

1980 Sept. D 4 1 Jan. 5 - July 19#

Oct. 162- 2 1 Nov. 300 3 1 1981 Sept. 59 1 1 April 19-May 28 Oct. 68 0.3 1 Sept. 1-Oct. 19 Nov. 192 0.7 1 1982 Sept. 0 0 0.3 Dec. 10-April 15#

-Oct. 0 0.2 0.3 Nov. 0 0.7 0.2 i

• Counted from X-rays i j/Prologged winter and early spring outages Note the delayed settlement of T. bartschi after the 1980 outage.

38

Table 12 Cumulative Panel Survival Rates A. B. gouldi - Bay (Stations 1, 2, 14, 15, 16, 17)

Month Year 76-77 77-78 78-79 79-80 80-81 81-82 1982 July 1 1.00 -

0.95 1.00 - -

Aug. 1.00 0.95 1.00 1.00 - 1.00 1.00 Sept. 0.99 0.95 1.00 1.00 1.00 1.00 1.00 Oct. 0.98 1.00 1.00 1.00 1.00 1.00 1.00 Nov. 0.87 0.90 1.00 1.00 1.00 0.95 0.91 Dec. 1.00 0.92 1.00 1.00 1.00 0.90 -

Jan. 1.00 1.00 1.00 1.00 1.00 0.95 -

Feb. 0.60 0.89 1.00 1.00 1.00 1.00 -

Mar. 0.63 1.00 1.00 0.98 1.00 1.00 -

Apr. 0.65 1.00 1.00 0.96 1.00 1.00 -

May 0.47 0.96 0.73 1.00 0.75 1.00 -

B. B. gouldi - Forked River and Forked River-Beach (Stations 4, 5, 6, 8, 9)

July -

1.00 -

0.95 - - -

Aug. 1.00 0.91 1.00 0.95 1.00 1.00 1.00 l Sept. 1.00 0.78 1.00 1.00 0.95 1.00 1.00 Oct. 1.00 0.96 1.00 0.99 0.96 1.00 1.00 Nov. 1.00 0.92 1.00 0.99 1.00 1.00 1.00 Dec. 1.00 1.00 1.00 1.00 0.95 1.00 -

Jan. 1.00 1.00 1.00 1.00 0.96 1.00 -

Feb. 0.66 0.91 0.85 0.94 0.96 1.00 -

Mar. 0.50 1.00 1.00 1.00 0.92 1.00 -

Apr. 0.07 1.00 0.67 1.00 0.96 0.86 -

May 0.07 0.91 0.84 0.91 0.96 0.83 -

C. B. gouldi - Oyster Creek (Stations 10, 11, 12, 13)

July - - -

1.00 - - -

Aug. 1.00- 1.00 1.00 0.92 -- - -

Sept. 1.00 1.00 1.00 1.00 0.93- 1.00 -

Oct. 1.00 1.00 1.00 0.67 1.00 1.00 1.00 Nov. 1.00 1.00 1.00 -1.00 1.00- 1.00 1.00 Dec. 1.00 1.00 1.00 1.00 1.00 - --

Jan. 1.00 0.93 1.00 1.00- '1.00 1.00 -

Feb. 0.88 0.90 1.00 -

.1.00 - -

Mar. 0.92 0.89 1.00 0.71 1.00 1.00 -

Apr. 0.93 0.88 1.00 0.86 1.00' 1.00 -

May 0.73 0.81 1.00 1.00 0.83 -- -

3 Dash = no shipworms in panel or no panel-39

. - - - . = . . . . . _ . .

i l

Table 12 cont.

D. T. navalis - Bay Month Year 76-77 77-78 78-79 79-80 80-81 81-82 1982 July -

1.00 -

1.00 1.00 1.00 1.00 Aug. 1.00 -

1.00 1.00 0.86 1.00 1.00 Sept. 1.00 0.00 1.00 1.00 1.00 1.00 1.00 Oct. 1.00 -

1.00 1.00 1.00 1.00 0.80 Nov. 1.00 1.00 0.94 1.00 1.00 0.90 1.00 Dec. 1.00 0.67 1.00 1.00 0.14 1.00 -

Jan. 1.00 0.50 1.00 1.00 0.25 0.73 -

Feb. 0.00 1.00 1.00 1.00 0.64 1.00 -

Mar. 1.00 -

1.00 1.00 0.67 1.00 -

Apr. 0.50 -

1.00 1.00 0.50 1.00 -

May 0.44 0.57 1.00 1.00 0.75 0.83 -

E. T. navalis - Forked River July -

1.00 -

1.00 1.00 0.94 1.00 Aug. 1.00 1.00 0.67 0.93- 1.00 0.86 0.83 4

Sept. 1.00 1.00 -

1.00 1.00 0.55 0.92

Oct. 1.00 1.00 1.00 0.98 0.60 0.58 0.69 Nov. 1.00 0.80 1.00 0.87 1.00 0.42 0.64 Dec. 1.00 1.00 1.00 1.00 1.00 0.21 -

Jan. 1.00 1.00 1.00 1.00 0.06 0.55 -

Feb. -

1.00 1.00 0.92 0.50 0.19 -

4 Mar. 0.50 0.50 1.00 1.00 0.25 0.00 -

Apr. -

0.75 1.00 1.00 0.11 0.13 -

May -

0.67 0.40 1.00 0.23 0.00 -

I F. T. navalis - Oyster Creek July - - -

1.00 1.00 1.00 -1.00 Aug. - -

1.00 1.00 1.00 1.00 1.00 Sept. - -

1.00 1.00 0.50 1.00 1.00 Oct. - - -

0.80 1.00 1.00 1.00

, Nov. -

1.00 -

1.00 1.00 0.25 0.50 Dec. -

0.00 1.00 1.00 1.00 '1.00- -

Jan. - - -

1.00 1.00 0.00 -

Feb.' - - - -

1.00 0.20 -

Mar. - --

0.00 1.00 0.67 - -

Apr. - -

0.00 -

1.00 0.33 -

, May -

1.00 -

0.38 -

0.33 -

i

Table 12 cont.

G. T. bartschi - Forked River Month Year 76-77 77-78 78-79 79-80 80-81 81-82 1982 July - - - - -

1.00 -

Aug. - - -

1.00 - - -

Sept. - -

1.00 0.42 - - -

Oct. - -

1.00 0.51 - - -

Nov. - -

1.00 0.22 1.00 - -

Dec. - -

1.00 -1.00 0.00 - -

Jan. - -

1.00 0.86 1.00 - -

Feb. - -

0.59 0.83 0.50 - -

Mar. - -

0.00 1.00 0.07 - -

Apr. - -'

O.00 0.00 0.10 - -

May - - -

1.00 0.00 0.04 -

l H. T. bartschi - Oyster Creek July - -

0.00 0.96 - - -

Aug. - -

1.00 0.997 -

0.93 -

3 Sept. - -

1.00 0.44 -

0.83 -

Oct. - -

0.99 0.23 0.67 0.93 -

Nov. -

1.00 0.62 0.18 0.91 0.91 -

Dec. -

1.00 0.43 1.00 1.00 0.87 -

Jan. -

1.00 0.76 1.00 0.71 0.66 -

Feb. -

1.00 0.29 -

0.01 0.80 -

Ma r. -

1.00 0.01 0.002 0.08 0.26 -

Apr. -

1.00 0.22 0.00 0.08 0.29 -

May -

0.40 0.001 0.00 0.00 0.20 -

l 41-

, - ~. .

A i

estimate of the rates for the Teredo spp. could be constructed by upward revisions to the denominators in winter and spring samples in most years.

Such estimates would merely accentuate the low survival rates in all i years for these species. Hence, the use of raw survival rates is conser-vative.

Inspection of Table 12 shows that survivorship in Bankia gouldi is high in all areas, compared with Teredo spp. Annual survivorship is lowest in Teredo bartschi. All species suffered higher-than-normal mortality in 1976-77, a year with a very cold winter in which the generating station had a prolcnged spring shutdown. Survivorship was uneven among panels in a cumulative series at any one station. Overall, there was not a' pattern of greater survivorship in any one geographical area. But in certain years, such a pattern did exist. For example, in 1976-77, more Bankia gouldi survived in Oyster Creek than elsewhere, perhaps due to the pres-ence of a thermal effluent in winter months. T. navalis survived poorly in Forked River in 1980-83, in the Bay in 1980-81, and in Oyster Creek in 1981-82. Microscopical and histological examination of tissues has led some workers to attribute this mortality pattern to infection by a Haplo-sporldlum species (Hillman et al., 1982).

4.1.2 Yearly Panels Total numbers of living shipworms in yearly panels were analyzed via Analysis of Variance (Table 13). The data were divided into two time periods in an attempt to stabilize the means through grouping months with similar exposure to shipworms. The two time periods chosen were October-December (fall) and February-June (spring). The first period is not represented in years 1 (1976-77) or 7 (1982-83). Statistical analyses were designed to be conservative, that is, to use stringent criteria to find significant differences between Oyster Creek and other station groups. Station groups were constructed first on the basis of the tem-perature and salinity data, then on geography alone, as described in the

~

table, parts A'and B, respectively.

In fall, 1977, using station groups A, there are no significant station-group differences, apparently because the variability among the six Bay control stations was substantially greater than that among groups. This remains the case even if the-Bay controls are represented only by sta-tions 1 and 14.

l In fall, 1978, the ANOVA for site differences is significant, 0.01 > P >

O.005. Applying Dunnett's test for a one-tailed comparison of Oyster Creek with - Forked River and creek and bay controls- significantly more 42 l

l

Table 13 ANOVA of Total Number of Shipworms Annual Panels F-values for stations or station groups are from adjusted denominator mean squares in most tables. Adj ustments reflect the unequal sample sizes.

Where added variance components have negative estimates, by convention this is best estimated by O.

t-values are compared with table values for one-tailed Dunnett compari-sons, for comparison of all other sites with Oyster Creek. Degrees of freedom are the same as in the " station" line of the ANOVA.

If station group comparisons and their t values are not given in the tables, none of the planned comparisons approached significance.

Abbrevi. uns for station groups and seasons in comparisons:

A. Station groups based on present hydrography; geography BC = Bay controls (#1, 2, 14, 15, 16, 17)

FR = Forked River (#4, 5, 6, 8)

CC = Creek controls (#3, 7, 20)

OC = Oyster Creek (#10, 11, 12) Station 13 in 1978-79

IC = Island controls (#18, 19)

Station 9 was excluded because of peculiar hydrography (heavy scour) and the very great frequency of missing data.

Fall = October - December Spring = February - June B. Station groups based on geography alone BCN = Bay controls north (#1, 2)

BCS = Bay controls south (#15, 16, 17)

CM = Creek mouths near effluent (#4, 8, 14)

CC = Creek controls (#3, 7, 20)

OC = Oyster Creek (#11, 12)

FR = Forked River (#5, 6)

IC = Island on outer bay (#18, 19) 43

Table 13 ANOVA of Total Number of Shipworms Annual Panels A. Station groups based on hydrography.

Added Variance Source SS df MS Component t F p Fall, 1977 Station group 1728.3 3 576.1 -181.7 <1 n.s.

Station 2367.3 10 2367.3 779.5 82.3 p<0.001 Month 805.3 28 28.8 28.8

$ Fall, 1978 Station group 4.824x108 4 1.206x108 86,385 5.89 .01>p>.005 OC vs CC 3.03 p<.01 OC vs FR 3.43 p<.01 OC vs BC 3.79 p<.01 Station 2.295x10 8 12 19,127 3.48 p<.005 Month 1.295x105 31 4,178 <1 n.s.

Error 1.176x10s 14 84,007 Fall,-1979 Station group 9.001x10 8 4 2.250x10 8 41,150 145.4 p<.001 OC vs CC 10.80 p<.01 OC vs FR 31.33 p<.01 OC vs BC 31.07 p<.01

' Station 62,998 6 10,500 -17,773 <1 n.s.

Month. 987,361 17 58,080 54,493 29.27 n.s.

l Error 1984.5 1 1984.5 1984.5

Table 13 (cont.)

ANOVA of Total Number of Shipworms Annual Panels, cont.

Added Variance Source SS df MS Component t F p Fall, 1980 Station group 95,530 3 31,843 -5,767 <1 n.s.

-Station 363,793 5 72,759 15,256 6.28 p<.001 Month 217,357 18 12,075 8,482 1039. p<.001 Error 139.5 12 11.6

, Fall, 1981 vi Station group 128,034 3 42,678 -10,717 <1 n.s.

Station 504,135 5 100,827 35,750 12.80 p<.001 Month 72,645 9 8,072 5,865 32.13 p<.001 Error 1,507.5 6 251 251 Spring'(June only), 1977 Station group- 642.3 3 214.1 47.5 3.69 .05>p>.025 Station 580.7 10 58.1 58.1 Spring, 1978-Station group 8,627 4 2157 74.2 1.76 n.s.

Station 14,397 12 1200 303.1 130.5 p<.001 Month 420 45 9.33 -2.3 <1 n.s.

Error ,

71 6 11.83 11.8

• Significant

Table 13 (cont.)

ANOVA of Total Number of Shipworms Annual Panels, cont.

Added Variance Source SS df MS Component t F p Spring, 1979 Station group 4.16x108 4 1.040x108 45,160 3.81 .05>P>.025 ,

OC vs CC . 1.68 p>.05(n.s.)

OC vs FR 1.78 p>.05(n.s.)

OC vs BC 1.71 p>.05(n.s.)

Station 2.93x108 l's 225,404 42,027 7.01 p<.001 Month 1.57x10 8 49 32,039 9,466 1.64 n.s.

, Error 430,205 22 19,555 29,555 e

Spring, 1980 Station group 3.40x10 8 3 1.13x10 8 109,305 21.91 p<.001 OC vs CC 8.29 p<.01 OC vs FR 9.87 p<.01 OC vs BC 9.83 p<.01 Station 179,012 5 35,802 8241 6.97 p<.01 Month 136,615 26 5,254 3369 3.91 .05>p>.025 Error. 8,054.5 6 1,342.4 1342 Spring, 1981 Station group 1736.8 3 578.9 -101.2 <1 n.s.

Station 9246.7 5 1849.3 260.5 14.93 p<.001 Month 4683.9 36 130.1 86.2 15.85 p<.001 Error 156.0 19 8.2 8.2

Table 13 (cont.)

ANOVA of Total Number of Shipworms Annual Panels, cont.

2 Added Variance Source SS df MS Compone't t F .p e

Spring,-1982 ,

. Station group 28,964 3 9655 423.9 1.44 n.s. .

Station 27,227 4 6807 960.2 1.91 n.s.

- Month 50,308 16 3144 -3375 <1 n.s.

, Error 44,176 6 7363 7363 r

B. Station groups based on geography,. comparing north and south bay stations and creek mouths.

Fall,-1977

. Station group 13,082 2 6541 277 1.63 n.s Station 16,046 4 4012 998 Month' 390. 21 19 19 216 <.001 Multiple Range test: Means Bay North 49.5 i

_ Creek Mouth 3.8 -

Bay South 0.4 l

i Fall, 1978 i

Station group 2,827 2 1413 22 1.24 n.s Station 4,774 5- 955 145 2.73 n.s

' Month 6,757 19 356 66 ,

Error 2,647 10 265 265 Multiple Range test: Means: Bay North 32.1, Creek Mouth 18.0, Bay South 6.4

Table 13 (cont.)

ANOVA of Total Number of Shipworms Annual Panels cont.

Added Variance Source SS df MS Component t F p Fall, 1979 Station group 12,154 1 12,154 -420 < n.s.

Station 24,901 2 12,451 2,369 5.54 .05>p>.01  ;

Month 27,398 12 2,283 930 Error 3,610 3 1,203 1,203 ,

Multiple Range test: Means Creek Mouth 95.0 Bay South 33.2

$ Fall, 1980 -

Station group 110 1 110 3.7 1.54 n.s.

Station 133 2 66 8.3 4.85 .05>p>.01 Month 163 12 14 -1.4 Error 175 11 16 15.9 Multiple Range test: Means Creek Mouth 6.61 <

Bay North 1.2I

• I (l

1

Table 13 (cont.)

ANOVA of Total Number of, Shipworms Annual Panels cont.

Added Variance Source SS df MS Component t F p Fall, 1981 Station group 459 .1 459 77 9.47 n.s.

Station 70 2 35 13 17.26 p<.001 Month 8 4 2 -3 Error 25 4 6 6 Multiple Range test: Means Creek Mouth 4.9

, Bay North 17.8 e ,

Spring (June only) 1977 Station group 329 2 164 62 6.91 .05>p>.01 Station 95 4 24 24 Month --

0 -- --

t Multiple Range test: Means Bay North 19.0 Creek Mouth 14.5 Bay South 3.3

Table 13 (cont.)

ANOVA of Total Number of Shipworms Annual Panels cont.

Added Variance Source SS df MS Component t F p Spring, 1978 Station group 1,033 2 516 -56 <1 n.s Station 4,032 5 806 257 57.5 p<.001 Month 221 16 14 7 Error 19 3 6 6 Multiple Range test: Means .

Bay North 39.7 i

, Creek Mouth 4.8 o Bay South 1.8 Spring, 1979 Station group. 2,134 2 1,067 -605 <1 n.s.

Station 23,193 3 7,731 1,200 7.09 p<.001 Month 17,308 17 1,018 -171 Error 9,936 8 1,242 1,242 Multiple Range test: Means Creek Mouth 32.5 Bay North 31.5 Bay South 7.0 P

V

~~ - - .

Table 13 (cont.)

ANOVA of Total Number of Shipworms Annual Panels cont.

Added Variance Source SS df MS Component t F p Spring, 1980 Station group 20,909 1 20,909 -3,283 <1 n.s.

Station 60,688 2 30,334 9,153 29.0 p<.001 Month 11,028 10 1,103 972 Error 72 1 72 72 Multiple Range test: Means u Creek Mouth 104.2

• Bay North 37.2 Spring, 1981

' Station group 280 1 280 26 28.2 p<.001 Station 7 2 4 -1 Month 122 12 10. -1 Error 90 8 11 11 Multiple Range test: Means Creek Mouth 8.0 Bay North 0.9

Table 13 (cont.)

ANOVA of Total Number of Shipworms Annual Panels cont.

Added Variance Source SS df MS Component t F p Spring, 1982 Station group 127 1 127 -100 <1 n.s.

Station 504 1 504 132 4.63 n.s.

Month 747 6 124 47 Error 187 3 62 62 Multiple Range test: Means u Bay North 16.7 b3 Creek Mouth 10.2 C. Station groups based on geography, comparing Oyster Creek, Forked River, and creek controls.

Fall, 1977 Creeks 1125.6 2 567.8 58.7 5.8 .1>p>.05 Station 295.2 3 98.4 16.0 2.9 n.s.

Month 617.0 18 34.3 34.3 Multiple Range test: Means OC 16.75 FR 5.12 CC 0.38

Table 13 (cont.)

ANOVA of Total Number of Shipwbras Annual Panels cont.

Added Variance Source SS df MS Component t F p Fall, 1978 Creeks 7.50x108 2 3.75x10 8 369,397 260. <.001 Station 38,966 3 12,989 -4,617 <1 n.s.

Month 337,313 17 19,842 -94,268 Error 1.18x108 8 147,381 147,381 Multiple Range test: Means u OC 1000.8

" FR 7.5 CC 0.0 Fall,.1979 Creeks 5.65x108 2 2.82x108 580,328 45.33 p<.001 Station 4,720 2 2,360 -28,097 <1 n.s.

Month 623,005 10 62,300 62,300 Multiple Range test: Means OC 1320.8 FR 142.0 CC 0.1

Table 13 (cont.)

ANOVA of Total Number of Shipworms Annual Panels cont.

Added Variance Source SS df MS Component t F p Fall, 1980 Creeks 80,173 2 40,087 -37,198 <1 n.s.

Station 270,106 1 270,106 48,366 11.31 p<.01

' Month 296,498 12 24,708 18,201

. Error. 40 6 7 7 Multiple Range test: Means

, OC 165.8

• FR 2.0 CC 0.0 Fall, 1981 Creeks 109,162 2 54,581 -112,400 <1 n.s.

Station. 434,341 1 '434,341 155,633 22.5 p<.01 Month 72,637 4 18,159 13,934 Error 1,482 2 741 741 Multiple Range test: Means OC 270.0 FR - 5.0 CC 0.5

Table 13 (cont.)

ANOVA of Total Number of Shipworms Annual Panels Added Variance Source SS df MS Component t F p Spring (June only) 1977

. Creeks 48 2 24 9 4.00 n.s.

Station 18 3 6 6 Month 0 Multiple Range test: Means OC 22.5 w_ FR 7.0

• CC 0.0 Spring, 1978 Creeks 579 2 290 24 3.36 n.s.  !

Station 249 3 83 19 10.67 p<.001 Month 96 16 6 -10 Error 52 3 17 17 Multiple Range test: Means OC 11.0 FR 8.0 CC 0.2

Table 13 (cont.)

ANOVA of Total Number of Shipworms Annual Panels cont.

Added Variance Source SS df MS Component t F p Spring, 1979 Creeks 3.96x108 2 1.98x108 190,252 36.95 p<.001 Station 3,357 4 839 -16,275 <1 n.s.

Month 1.07x108 16 66,722 17,360 Error 388,179 9 43,131 43,131 Multiple Range test: Means

, OC 771.5

• FR 5.4 CC 0.2 Spring, 1980 Creeks 1.4x10s 2 715,899 153,733 54.6 p<.001 Station ----

0 ---- ---- ---- ----

Month 113,883 9 12,654 11,021 Error 0 2 0 0 Multiple Range test: Means OC 762.5 FR 191.2 CC 0.2

i Table 13 (cont.)

ANOVA of Total Number of Shipworms Annual Panels Added Variance Source SS of MS Component t F p Sp ring , 1981 Creeks 2,394 2 1,197 -1,160 <1 n.s.

' Station 8,778 1 8,778 1,602 37.73 p<.001 Month 2,848 12 237 169 Error 41 6 7 7 Multiple Range test: Means u OC 31.8 FR 3.2 CC 0.1 Spring, 1982 Creeks 31,852 2 15,926 2,153 2.31 n.s.

Station 5,512 1 5,512 -30 <1 n.s.

Month 49,561 8 6,195 -6,774 Error 43,990 3 14,663 14,663 Multiple Range test: Means OC 88.2 FR 5.7 CC 0.3

-- a- -. ._.-- - - - - - _ _ _ . - - - - - -

shipworms were found in Oyster Creek (P < .01). In fall, 1979, a signif-icant F-ratio is also found in the ANOVA, P < 0.001. Again, applying Dunnett's one-tailed test, significantly more shipworms were in Oyster Creek than at Forked River, creek, or bay controls (P < 0.01). It is in-teresting that the shipworm attack in Oyster Creek exceeded not only the creek controls, but bay stations as well. The years 1978 and 1979 had relatively little outage of the generating station compared with 1977, 1980, and 1982.

In fall, 1980 and 1981, and spring, 1981 and 1982, the ANOVAS are not significant at the station-group level and no comparisons of Oyster Creek with other station groups approached significance.

For the February to June data block, year 1 is represented only by the month of June, 1977. In this analysis, the station groups have a signi-ficant mean square, but the one-tailed comparisons of Oyster Creek with other station groups are not significant. The largest mean is for Forked River, but using a posteriori tests (Student-Newman-Keuls procedures), no differences are significant.

In spring 1978, the station group level does not yield a significant F ratio, and the Oyster Creek comparisons are not significant. Island control stations have many more shipworms on average than do other sites, but these differences do not quite achieve significance in a posteriori tests. Neither restricting the analysis to fewer stations, nor analysing the log of (total + 1), alters the results.

February to June (1979) data make an interesting comparison with the fall, 1978 data. While fall, 1978 results were significantly different for Oyster Creek, this was not the case in the following spring. Since no shipworm settlement occurred in the interim, the loss of shipworms through winter mortality in Oyster Creek must be responsible.

In February to June 1980, the station group level generates a highly significant F ratio in the ANOVA (P < 0.001) . The comparisons of Oyster Creek with Forked River, Bay control and Creek control station groups are all significant at P < 0.01.

The mean total number of shipworms in Oyster Creek for the third year of the study was reduced by the inclusion of station 13 near the power plant outfall. The velocity there was so great that virtually no boring or fouling organisms could survive. Inclusion of this station, therefore, reduced the statistical significance of differences between Oyster Creek

'and other station groups.

58

.. . .)

l l

i The alternative and more finely divided station groups are analyzed in Table 13B and C. Comparing stations 4, 8 and 14 (creek mouth at the edges of the thermal effluent) with north and south bay controls (13B),

none of the results were significant in fall. Within-station variance was high. In spring, 1977, there was a weakly significant difference be-tween the three groups using the multiple range test. Only in the spring of 1981 was there clearly a greater number of total shipworms at the ex-perimental stations 4, 8 and 14 than at

• controls. Overall, one can con-clude that there was not a greater total number of shipworms on the average at these stations than at other bay and creek-mouth stations in Barnegat Bay during 1977-1982. The inclusion of station 14 with 15-17 as bay controls is justified. There remained a problem with stations 4 and 8, from their species composition (the presence of numerous Teredo bartschi) clearly showed a thermal effluent influence.

Comparisons between Oyster Creek, Forked River, and the creek control group are in part C of Table 13. In several years, the difference be-tween stations 11 and 12 swamp the effect of Oyster Creek versus the other creeks. It is interesting that the gradient of shipworm abundance in Oyster Creek and Forked River is not from creek mouth upstream as one might predict under no rma l conditions. In Oyster Creek, it is the re-verse, station 12 > 11 >> 10. In Forked River, it is station 4 = 5 > 6, where station 6 is in a side branch lagoon.

In all years for fall cumulative samples, the order of shipworm abundance was Oyster Creek > creek controls. These differences were marginally significant in 1977 and highly significant in 1978 and 1979, but not, so in the fall of 1980 af ter the prolonged outage of January-July 1980. The variance within the Oyster Creek group prevented the 1981 results from reaching significance. The variance was caused by a high number of Teredo bartschi at station 12 recovering from a population crash in 1980, but not yet spread downstream to station 11.

For spring samples, Oyster Creek had significantly more shipworms than the other groups in 1979 and 1980, but in every year except one, Oyster Creek > Forked River > creek controls. In June, 1977, Forked River sur-passed Oyster Creek.

Despi,te the lack of statistical significance in many of these results (Table 13C), the very low number of shipworms in the creek controls (means of 0.0-0.38) compared with Forked River (means of 2.0-191.2) and Oyster Creek (means of 7.0 - 1320.8) reveal biological significance. The differeace in potential damage between the consistent presence of 0-2 shipworms and even 5-10 shipworms per panel is important even though the numbers are all small.

59

The yearly shipworm data for living specimens were analyzed for the fall cumulative data set by species. Using the first station groups, fo r Bankia gouldi (Table 14), only in fall, 1979, did station group differ-ences approach significance. B. gouldi was more abundant in Forked River than Oyster Creek. Teredo navalis was significantly more abundant at the island control stations in Fall, 1979. Teredo bartschi was more abundant at Oyster Creek than at Bay and Creek control stations in all years, be-cause it was virtually absent at control stations. Thus, no formal sta-tistics are necessary to test the significance of the results. However, an example is given in Table 14. Results in table 14 would be of higher significance if living and dead specimens had been analyzed. l Table 15 gives the ANOVA's for the second set of station groups. Part A compares the bay stations with the marginally thermally influenced creek mouth stations 4, 8, and 14. Bankia gouldi was not more abundant in any one station group, but it tended to be more abundant in the north, espe-cially in 1977 and 1978. Teredo navalis was usually more abundant in the south than at the northern stations, but not significantly so. Teredo bartschi was rarely found at bay stations but when it was, it was only in the thermally influenced group. Although the means are too low and within group variances too high for the results to be significant at the

.05 level, the absence of T. bartschi from the bay control groups is an important finding. Within group variance is high because station 14 within the experimental group had T. bartschi only once.

Part B of Table 15 compares Oyster Creek, Forked River, and the creek controls. Station groups are as in Table 14. Bankia gouldi had signifi-cantly higher numbers in Oyster Creek in 1979 only. The fewest number of B. gouldi was always in the creek controls; the same is true for Teredo navalls. The difference between Oyster Creek and the other groups is clearly in the distribution of Teredo bartschi, as seen in the last page of Table 15. Even where results are not statistically significant due to high variance within station groups (i.e., 1980 and 1981), the multiple range test means show a biologically important difference. Oyster Creek contained T. bartschi, the other stations did not. This is the factor that causes the totals for 1978 and 1979 (Table 13) to be higher for Oyster Creek than for the other station groups.

4.2 Reproduction and Seasonal Settlement 4.2.1 Monthly Panels Colonization of monthly panels provides a direct, although incomplete, measure of the temporal pattern of shipworm settling. In our quarterly 60

Table 14 ANOVA of Number of Living Specimens, Annual Panels, Fall Months Stations Grouped According to Hydrography  !

l A. Bankia gouldi, 1979 SS df MS AVC t F. p Source 5137 4 1284 206 7.76 .025>p>.01 Station group OC vs CC 0.15 n.s.

-4.20 n.s.

OC vs'FR

-2.50 n.s.

OC vs BC Station 1099 6 183 29 1833 17 108 -597 <1 n.s.

Honth Error 722 1 722 722 B. Teredo bartschi, 1978 Station group 4.004x10 8 4 1.001x10 8 73,104 651 .01>p>.005 OC vs CC 2.96 .05>p>.01 OC vs FR 3.32 p<.01 OC vs BC 3.96 p<.01 Station 1.734x10s 12 144,503 38,585 19.34 p<.001 Month 186,446 31 6,014 -55,163 <1 n.s.

Error 1.081x10 8 14 77,193 77,193

. . _ = . . - - . _ _.

a Table 15 ANOVA of Number of Living Specimens, Annual Panels, Fall Months Stations Grouped According to Geography A. Comparsion of bay north, bay south, and thermally-influenced creek mouth stations 1

Bankia gouldi, 1977 3

Source SS df MS AVC F p Bay 11,698 2 5,849 239.8 1.60 n.s.

Station 14,625 4 3,656 912.9 816 P<.001 Month 94 21 4.5 4.5 Multiple Range Test Means BCN 46.5 CH 2.6 BCS 0.4 1978 Bay 4,167 2 2084 111 2.83 n.s.

Station 3,182 5 636 69 1,81 n.s.

Month 6,804 19 358 82 Error 2,456 10 246 246 Multiple Range Test Means BCN -31.6 CM 14.9 BSC 1.8 1979 Bay 84 1 84 -186' <1 n.s.

Station 2,686 2 1,343 271 7.62 .01>p>.005 Month 2,074 12 173 - 88 Error 824 3 275 275 Multiple Range Test Means BCN 20.8 CM 30.4 1980 i Bay 6.2 1 6.2 -1.0 <1 n.s.

l Station 30.4 2 15.2 1.8 4.54 .05>p>.01 i Month 40.4 12 3.4 0.1 l Error 35.0 11 3.2 3.2 l

Multiple Range Test Means BCN 0.75 i

CM 2.33 62 l

Table 15 cont.

1 Source SS df MS AVC F p l 1981 Bay 600.0 1 600.0 110.0 45.0 .05>p>0.1 Station 20.0 2 10.0 3.6 5.06 .05>p>.01 Month 3.0 4 0.8 -1.7 Error 13.0 4 3.2 3.2 l Multiple Range Test Means l BCN 16.2 1.6 CM Teredo navalis, 1977 Bay 0.73 2 0.37 .02 2.34 n.s.

Station 0.62 4 0.16 .01 1.19 n.s.

Month 2.75 21 0.13 .13 Multiple Range Test Means BCN 0.4 CM 0.2 BCS 0.0 1

1978 Bay 201.0 2 101 -1.3 <1 n.s.

Station 455 5 91 21.1 27.7 p<.001 Month 67 19 3.5 2.5 Error 1 10 0.1 0.1 Multiple Range Test Means BCS 4.6 CM 0.5 BCN 0.1 i,

1979 Bay 680 1 680 1.3 1.02 n.s.

! Station 1,091 2 545 103.7 5.51 .05>p>.01 Month 1,189 12 99 3.7 Error 284 3 95 94.8 l

Multiple Range Test Means

! CM 16.9 l

BCN 3.8 l

63.

Table 15 cont.

1980 Source SS df MS AVC F p Bay 10.7 1 10.7 -0.4 <1 n.s.

Station 27.0 2 13.5 1.7 5.46 0.5>p>.01 Month 28.9 12 2.4 -0.8 Error 42.0 11 3.8 3.8 Multiple Range Test Means CM 1.8 BCN 0.8 1981 Bay 4.2 1 4.2 0.2 1.41 n.s.

Station 4.5 2 2.2 -0.1 <1 n.s.

Month 11.0 4 2.8 1.3 Error 3.0 4 0.8 0.8 Multiple Range Test Means CM 1. 5 '

BCN 0.5 l Teredo bartschi,1977. No Specimens on any panel.

1978 Bay 33 2 17 -1.6 <1 n.s.

Station 140 5 28 6.3 15.4 p<.001 Month 35 19 1.8 1.3 Error 0 10 0.0 0.0 Multiple Range Test Means CM 2.4 BSC 0.0 BCN 0.0 1979 Bay 119 1 119 -52 <1 n.s.

l Station 848 2 424 77 4.52 .05>p>.01 l Month 1165 12 97 84 Error 0 3 0 0 l

I j Multiple Range Test Means CM 5.8 BCN 0.0 64

Table 15 cont.

Teredo bartschi, 1980 Source SS df MS AVC F p  :

j Bay 0.05 1 0.05 -0.04 <1 n.s.

Station 0.80 2 0.40 0.03 1.68 n.s.

Month 3.00 12 0.25 0.14 Error 0.00 11 0.00 0.00 Multiple Range Test Means i CM 0.17 BCN 0.00 1981 No specimens on any panel.

B. Comparison of Oyster Creek, Forked River, and creek controls Bankia gouldi, 1977 Creeks 403 2 201.5 11.5 1.85 n.s.

Station 327 3 109.1 25.0 18.84 p<.001 Month 104 18 5.8 5.8 Multiple Range Test Means OC 10.4 FR 4.6 CC' O.4 1978 Creeks 247.5 2 123.7 -0.55 <1 n.s.

Station 312.5 3 104.2 22.61 111 p<.001

! Month 17.9 17 1.05 0.73 Error 0.5 8 0.06 0.06 l Multiple Range Test Means l FR 6.50 l OC 0.06 CC 0.00 1979

Creek 1,901.7 2 950.8 193.2 288 p<.001 l

Station 0.38 2 0.2 -1.8 <1 n.s.

Month 39.25 10 3.9 3.9 Multiple Range Test Means FR 2.60 OC 0.8 l CC 0.2 i 65

- - .. . . - . ~. .. .

Table 15 cont.

Source SS df MS AVC F p 1980 Creeks 9.55 2 4.77 0.24 1.53 n.s.

Station 3.12 1 3.12 0.35 2.37 n.s.

Month 15.11 12 1.26 -1.22 Error 17.50 6 2.92 2.92 Multiple Range Test Means OC 1.3 2 FR 0.5 CC 0.0 1981 i

Creeks 0.67 2 0.33 .01 <1 n.s.

Station 0.33 1 0.33 .09 3.33 n.s.

Month 0.50 4 0.12 .30 Error 1.00 2 0.50 .50 i

i . Multiple Range Test Means FR 1.0 CC 0.5 OC 0.2 Teredo navalis, 1977 Creeks 42.25 2 21.12 1.76 2.98 n.s.

Station 21.25 3 7.08 0.21 1.13 n.s.

Month 112.50 18 6.25 6.25 Mulitple Range Test Means OC 2.88

FR 0.12 CC 0.00 1978 Creeks 5.14 2 2.57 -0.07 <1 n.s.

Station 8.14 3 2.71 0.52 7.67 p<.001 Month 6.50 17 0.38 0.19 Error 1.00 8 0.12 0.12 Mulitple Range Test Means FR 1.0Q OC 0.12 CC 0.00 l

l 66

.1

Table 15 cont.

Source SS df MS AVC F p 1979 Creeks 501 2 251 54.6 10.97 p<.001 Stati.on 0.3 2 0.2 -12.8 <1 n.s.

Month 274 10 27.4 27.4 Multiple Range Test Means FR 13.25 OC 0.25 CC 0.00 Teredo navalis, 1980 Creeks 2.57 2 1.29 .02 <1 n.s.

Station 1.43 1 1.43 0.22 4.96 .05>p>.01 Month 3.00 12 0.25 .86 Error 8.50 6 1,42 1.42 Multiple Range Test Means FR 0.75 OC 0.56 CC 0.00 1981 Creeks 10.00 2 5.00 1.79 5.56 n.s.

1 Station 0.00 1 0.00 .45 <1 n.s.

Month 4.50 4 1.12 0.90 Error 0.00 2 0.00 0.00 Multiple Range Test Means FR 2.50 OC 0.00

< CC 0.00 Teredo bartschi, 1977 Creeks 14 2 7.0 0.25 1.40 n.s.

Station 15 3 5.0 -0.25 <1 n.s.

Month 109 18 6.0 6.04 l Multiple Range Test Means OC 1.62 FR 0.00 CC 0.00 67

l Table 15 cont. l l

Source SS df MS AVC F p l l

1978 Creeks 5.7x108 2 2.8x108 273,111 53.9 p<.001 Station 206,528 3 68,843 8,731 2.38 N.S.

Month 212,540 17 12,502 -109,175 Error 1.3x10 8 8 160,210 160,210 Multiple Range Test Means OC 824 FR 0 CC 0  !

Teredo bartschi, 1979 Creeks 31,524 2 15,762 1,975 2.62 n.s.

Station 8,856 2 4,428 1,083 2.09 n.s.

Month 21,169 10 2,117 2,117 Multiple Range Test Means OC 90.2 FR 29.8 CC 0.0 1980 Creeks 64,476 2 32,238 -31,769 <1 n.s.

Station 225,667 1 225,667 39,469 9.12 .05>p>.01 Month 307,101 12 25,592 18,857

• Error 0 6 0 0 Multiple Range Test Means OC 149 FR 0 CC 0 1981 Creeks 84,225 2 42,112 -84,569 <1 n.s.

Station 328,021 1 328,021 118,209 2.56 .1>p>.005 Month 48,131 4 12,033 9,160 Error 1,165 2 582 582 Multiple Range Test Means OC 270 FR 0 CC 0 1

68

. _ . - . _ _ _ .__m _ _ _ . _ .. __ _ ._;

reports we have noted that more settlement occurs on cumulative and j yearly panels, which have been exposed longer. However, on those panels, it is difficult to distinguish spring settlement from small individuals that settle in fall and fail to grow until spring.

Total shipworms (alive and dead) were averaged within stations and then over all stations within a station group to yield monthly estimates of average number of colonists per panel. These are presented in Table 16 for the years 1976-1982, beginning with the monthly panels deployed in June, 1976. The incompleteness of the sett.lement record is illustrated by the creek control group, since none of its monthly panels'were ever colonized yet some cumulative and yearly panels were (e.g., Table 10).

Table 16 includes analyses based on the two station groupings described in the methods.

Except in 1976 and 1982, colonization at Oyster Creek was extended one to two months later in the year compared with Forked River and bay stations.

In 1980 and 1981, colonization appeared to be one month delayed in Oyster Creek. These patterns can be interpreted in the light of the species present in each station group, and operations of the generating station.

The sett.lement. pattern in Oyster Creek is dictated by the activity of T.

bartschi, which settles over more months than the native species. In j 1976, a prolonged outage and cold weather reduced the adult. population of shipworms and nearly eliminated Teredo bartschi. In 1980, a prolonged outage caused a delay in reproduction of T. bartschi (Table 11). In 1982, a prolonged outage eliminated Teredo bartschi from our sampling areas.

The average number of colonists per station group, summed over months, is appreciably higher in Oyster Creek than at bay, creek, or Forked River stations in years 1978-1981. As Table 17 indicates, this pattern is borne out even if only the stations sampled in all years (sta. 1, 4, 5, 8, 10, 11, 12, and 14) are considered. Again, Teredo bartschi is re-

sponsible for the pattern. Creek mouths influenced by the ef fluent do not have more shipworm settlement. than control bay stations.

Another comparison of interest is between the Long Beach Island stations and all other station groups. In the three years when samples were taken, 1977-1980, the number of colonists was even greater there than in Oyster Creek. This was due to the presence of one species, Teredo l navalis, which prefers the offshore area.

69 l

l 1

l

Table 16 Average Number of Colonists (Alive & Dead) on Monthly Panels

+

(all species, averaged within stations and over stations within station group)

A. Station Groups Based on Hydrography and Geographical Location

]

[

1976 Station Group Bay Forked Oyster Creeks July 6.67 4.25 0.00 0.00 Aug. 7.67 12.75 2.67 0.00 Sept. 0.67 1.00 0.00 0.00 Oct. 0.00 0.25 0.00 0.00 Nov. 0.00 0.00 0.00 0.00 i 1977 Bay Forked Oyster Creeks Island July - - - - -

Aug. 5.67 5.25 4.33 0.00 4.50 i Sept. 0.00 0.00 0.25 0.00 80.00 Oct. 0.00 0.00 0.75 0.00 60.50 Nov. 0.00 0.00 0.00 0.00 0.00 1978 Bay Forked Oyster Creeks Island July 0.00 0.50 5.00 0.00 0.00 Aug. 1.75 1.25 27.00 0.00 25.00 Sept. 9.50 1.00 26.60 0.00 360.00 Oct. 0.00 0.00 1.00 0.00 1.50 Nov. 0.00 0.00 0.00 0.00 0.00 1979 Bay Forked Oyster Creeks Island July 26.67 39.33 82.40 0.00 0.00 Aug. 30.50 21.67 12.00 0.00 251.00 Sept. 2.50 17.67 373.20 0.00 600.00 Oct. 0.00 0.00 36.80 0.00 0.00

Nov. 0.00 0.00 0.00 0.00 0.00 i

1980 Bay Forked Oyster Creeks

- July 0.00 .0.33 0.00 0.00 Aug. 1.50 2.00 0.67 '0.00 Sept. 0.00 0.00 0.33 0.00 l Oct. 0.00 0.33 39.67 0.00 Nov. 0.00 0.00 11.67 0.00 70-

Table 16 cont.

1981 Bay Forked Oyster Cret.ks July 3.00 2.33 0.00 0.00 Aug. 2.50 2.00 1.33 0.00 Sept. 0.00 0.00 2.00 0.00 Oct. 0.00 0.00 12.33 0.00 Nov. 0.00 0.00 0.00 'O.00 1

1982 By Forked Oyster Creeks July 0.00 0.00 0.00 0.00 Aug. 2.00 17.33 0.33 0.00 Sept. 0.50 0.33 0.00 0.00 Oct. 0.00 0.00 0.00 0.00 Nov. 0.00 0.00 0.00 0.00 B. Average Nember of Colonists (excluding Stations 9, 10, 13, 18, 19) Alive and Dead on Monthly Panels, Station Groups based on Geographical Location Alone Station Group 11,12 5,6 3,7,20 15,16,17 1,2 4,8,14 Oyster Forked Creek South North Creek Creek River Controls Bay Bay Mouths 1976 July 0.0 7.5 0.0 0.0 20.0 0.67 Aug. 2.5 3.5 0.0 2.0 18.0 16.0 Sept. 0.0 0.5 0.0 0.0 1.0 1.67 Oct. 0.0 0.0 0.0 0.0 0.0 0.33 Nov. 0.0 0.0 0.0 0.0 0.0 0.0 l

! 1977 l July -- -- -- --

Aug. 5.5 5.0 0.0 -4.0 11.0 3.67 Sept. 0.5 0.0 0.0 0.0 -0.0 0.0 Oct 1.0 0.0 0.0 0.0 0.0 0.0 Nov. 0.0 0.0 0.0 0.0 0.0 0.0 l

71

Table 16 cont.

1978 Oyster Forked Creek South North Creek Creek River Controls Bay Bay Houths July 10.0 0.0 0.0 0.0 0.0 0.67 Aug. 65.0 0.5 0.0 0.0 3.5 1.33 Sept. 65.0 1.0 0.0 1.0 18.0 1.0 Oct. 2.5 0.0 0.0 0.0 0.0 0.0 Nov. 0.0 0.0 0.0 0.0 0.0 0.0 1979 July 198.5 56.0 0.0 --

40.0 20.67 Aug. 26.0 7.0 0.0 --

57.0 20.67 Sept. 183.0 20.0 0.0 --

4.0 11.33 Oct. 39.0 0.0 0.0 --

0.0 0.0 Nov. 0.0 0.0 0.0 --

0.0 0.0 1980 July 0.0 0.0 0.0 --

0.0 0.33 Aug. 0.5 2.0 0.0 --

0.0 2.33 Sept. 0.5 0.0 0.0 --

0.0 0.0 Oct. 59.5 1.0 0.0 --

0.0 0.0 Nov. 17.5 0.0 0.0 --

0.0 0.0 1981 July 0.0 2.0 0.0 --

1.0 3.33 Aug. 2.0 0.0 0.0 --

5.0 2.0 Sept. 3.0 0.0 0.0 --

0.0 0.0 Oct. 18.5 0.0 0.0 --

0.0 0.0 Nov. 0.0 0.0 0.0 --

0.0 0.0 1982 July 0.0 0.0 0.0 --

0.0 0.0 Aug. 0.5 20.0 0.0 --

4.0 10.67 Sept. 0.0 0.0 0.0 --

1.0 0.33 Oct. 0.0 0.0 0.0 --

0.0 0.0 Nov. 0.0 0.0 0.0 --

0.0 0.0 A dash = no data

~72 l

l l

i

Table 17 Average Number of Colonists (Alive & Dead) on Monthly Panels (all species, averaged within stations and over stations within station group, using stations 1, 4, 5, 8, 10, 11, 12 and 14) 1976 Station Group

( 1,14 4,5,8 10, 11, 12 Bay Forked Oyster July 0.00 3.33 0.00 Aug. 6.00 16.33 2.67 Sept. 1.00 1.33 0.00 Oct. 0.00 0.33 0.00 Nov. 0.00 0.00 0.00 1977 Bay Forked Oyster July - - -

Aug. 0.50 5.00 4.33 l' Sept. 0.00 0.00 0.33 Oct. 0.00 0.00 1.00 Nov. 0.00 0.00 0.00 1978 Bay Forked Oyster July 0.00 0.67 8.33 l Aug. 0.50 1.67 45.00

.4 Sept. 18.00 1.33 44.33 l Oct. 0.00 0.00 1.67 i

Nov. 0.00 0.00 0.00 1979 Bay Forked Oyster July 32.50 39.33 135.67 Aug. 30.50 21.67 19.33 Sept. 2.50 17.67 622.00 Oct. 0.00 0.00 61.33 Nov. 0.00 0.00 0.00 1980 Bay Forked Oyster July 0.00 0.33 0.00 Aug. 1.50 2.00 0.67 Sept. 0.00 0.00 0.33 Oct. 0.00 0.33 39.67 Nov. 0.00 0.00 11'.67 73

Table 17 cont.

1981 Bay Forked Oyster July 3.00 2.33 0.00 Aug. 2.50 2.00 1.33 Sept. 0.00 0.00 2.00 Oct. 0.00 0.00 12.33' Nov. 0.00 0.00 0.00 i

1982 Bay Forked Oyster July 0.00 0.00 0.00 Aug. 2.00 17.33 0.33 Sept. 0.50 0.33 0.00 Oct. 0.00 0.00 0.00 Nov. 0.00 0.00 0.00

}

4 1

t 74 i

I t " t?

l a-

l l

4.2.2 Gonad Studies l l

One way to follow gonadal development without making histological prepar-ations or gonad squashes of each specimen is to observe changes in gonad size relative to somatic tissues. This was done for Bankia gouldi during 1977-1978. There were too few Teredo navalis in Oyster Creek for any meaningful analysis. Reproduction in T. navalls and T. bartschi can be observed more directly by observing larvae in the brood pouch, as dis-cussed in the next section. Some of the data on B. gouldi were presented in our quarterly reports NUREG/CR-0223, 0634, and 0812. However, a few more data points now have been added. The data are summarized in Table 18 and illustrated in Figure 7.

For both station groups and both years, gonad size reached a peak in June or early July and rapidly declined as spawning occurred, primarily in July. By November, it was difficult to separate the small amount of gonadal material from the rest of the tissues. The gonad / total tissue was generally larger in Oyster Creek than at other stations except in August and November, 1977 and July, 1978. The latter difference was due to slower build-up of the gonads at control stations than in Oyster Creek, and slightly later spawning. The August, 1977 low in Oyster Creek may be only an anomaly in sampling, or an intense period of spawning followed by a recovery in September and second spawning. The lack of healthy adult B. gouldi in Oyster Creek panels removed in October pre-vents full analysis of trends in the data. One reason for the larger gonads in Oyster Creek may be scaling: larger shipworms tend to be female and to have a proportionately larger gonad. It is interesting that gonad size was relatively greater in Oyster Creek even in June-July, 1977, when the generating station was not operating.

i Because of small sample size and high within group variance, partly because the statistic used is a ratio, the differences in Table 18 were for the most part nonsignificant when compared using t-tests (p >.05).

Nevertheless, the trends in the data are strong and, as noted above, have

! a possible biological interpretation. The heated effluent, plus increase ~d water circulation leading to plentiful planktonic food supply in Oyster Creek even when the generating station is not operating, proba-bly allow for greater growth and. gonad development of shipworms living there. Gonad development reaches its peak earlier in Oyster Creek.

4.2.3 Brooding i

The presence of larvae in the brood pouch is an indication of the length of the reproductive season in species of Teredo (Table 19). However,'the data must be interpreted cautiously. Teredo bartschi, according to 75 4

I

Table 18 Ratio of Ash-Free Gonad Weight: Total Tissue Weight Bankia gouldi, Combined Yearly and Cumulative Panels Oyster Creek 1 Other Stations 2 Plant Ratio S.D. N Ratio S.D. N Status 1977 June * .495 .126 7 * .476 .122 18 off July .232 .089 4 .200 .108 20 off Aug. .103 .022 12 .188 .089 14 on Sept. .420 .066 7 .197 .115 40 on Oct. 0 .090 .046 31 on Nov. .060 .024 5 .086 .041 60 on 1978 Mar. .151 .077 15 .112 .036' 5 on Apr. .185 .072 16 .120 .018 34 on May .156 .093 18 .086 .013 33 on June *.276 .122 24 .267 .184 52 on July .252 .151 19

• 319

. .090 29 on i Aug. No Data on Sept. .166 .050 6 .123 .034 85 on/off Oct. .053 .007 4 .048 .009 105 off 1

Stations 10, 11, 12, 13.

2 Stations other than the above. (Not all shipworms were included.)

• Highest yearly value, each station group.

l i

t l

l 76

l l

l I

l l

Figure 7 Seasonal telationship of gonad ash-free dry weight to total ash-free dry weight. Bankia gouldi. Adult specimens only, taken from cumulative and yearly panels submerged at least 3 months. Oyster Creek = mean of stations 10, 11, 12, 13. Bars are standard deviations. Sample sizes are in Table 18.

o OYSTER CREEK

& OTHER STATIONS

.5 0 ,- o di

.4 6-- ,

e  :: o z ..

0 w .4 0 .. .

g ..

3 O *30-~

O ..

to --

o

-8

< .3 0 .- .

F --

o o  :: n 0

t" . 2 5 .. .

p .. o z --

U .205~ - a a w --

45 o 3  :: o O .152 O z

0 1 o T

C

.10 .- . 46 l.*

1 f

' " 8 "" 44

> > i i i i i i i i i i i e i i i z e o. > > o z e E z > z .a e o. e d a us o o m < m < o. < :s s a m o

,s ' < m o z o , u. 2 < 2 7 ' < m o 1977 1978 MONTH 77

I Table 19 l Fraction of Adult Specimens Found with Larvae in the Brood Pouch ,

A dash indicates no specimens were present that month. P = larvae present but not quantified. There were very few T. bartschi during months with asterisks.

A. Teredo navalis - Oyster Creek Jan Feb Mar Apr May Jun Jul A3 Sept Oct Nov Dec 1978 0 0 -

0 1979 - - - - -

1.00 .25 .67 1.00 0 0 0 1980 0 -

0 0 0 -

0 0 0 0 0 0 1981 0 0 0 0 0 -

.50 .50 .75 .67 0 0 1982 -

0 -

0 0 -

0 .67 .33 1.00 1.00 B. Teredo navalis - Other stations Jan Feb Mar Apr May Jun Jul Aug Sept Oct Nov Dec 1978 0 0 0 0 0 .01 .02 .01 0 1979 0 0 0 0 .67 .29 .15 .08 .25 .11 0 0 1980 0 0 0 0 .31 .12 .30 .40 .40 0 0 0 1981 0 0 0 0 0 0 0 .46 .79 .75 .31 0 1982 0 0 0 0 0 0 0 .61 .11 .04 .55 l

l l C. Teredo bartschi - Oyster Creek and Forked River l

Jan Feb Mar An May Jun Jul A_ug Sept Oct Nov Dec 1978 .39 .34 .26 .39 1979 .37 .26 .24 P* P* .86 .04 .41 .65 .58 .48 .38 l 1980 .39 .47 0* -

0* 0* - - -

.81 .67 .54 l

1981 .38 .10 P* P* -

.10* 0* 1.00 .62 .87 .63 .55 1982 .23 1.00 .38 .20 .18 0 0 0 - - --

78

Table 19, holds larvae virtually all year long; yet I have not observed the release of larvae when the water temperature was below 16 *C. The finding of larvae in the brood pouch all year does show the flexibility of T. bartschi relative to the native species. It is able to respond quickly to favorable temperatures.

t When combined with data on settlement of larvae and gonad studies, it is j clear that Bankia gotildi has the shortest reproductive season of the three species, and that settlement seasons of the species are only par-

tially overlapping. Teredo bartschi usually has a higher percentage of I

adults brooding larvae thn T. navalis does at any one time (Table 19).

1 It must also have a hishly skewed sex ratio towards female in many panels, since in some cases (e.g. August and October, 1981) nearly all adults were found brooding young, i

Implications of the brooding data are that the life histories of the

. three species differ, causing a reduction in competition for space among settling larvae. The species differ in ability to take advantage of sudden environmental change. Teredo bartschi is the most. opportunistic of the species, as seen by its year-round brooding, its high percentage of adults carrying young, and its female-biased sex ratio.

It should be remembered that Teredo bartschi is considered a protandrous hermaphrodite, although there is histological evidence that many indivi-i duals may be simultaneous hermaphrodites (Richards et al., 1978; 1980).

Histological examination of a few adult Teredo bartschi has been done as a part of this p roj ect. Of 25 specimens examined from Oyster Creek collected in summer or fall,16 were female, 5 were male, and 4 possessed ambivalent gonads.

For Terodo navalis, there was variation in the period of brooding from year to year and between station areas. The brooding period in Oyster Creek was no longer than in any other single area, although the percen-tage of specimens with larvae tended to be higher (Table 19). In many months, no or very few specimens of T. navalis were recovered from Oyster Creek, hence records'of brooding are incomplete. The overall period of brooding, May to November, corresponds fairly well with data on settle-

, ment. of T. navalis, from June to October. Those adults still brooding in l November may not have succeeded in producing viable young in~most in-l stances. Years in which brooding started by early May (1979, 1980) had a tapering off of brooding by October.

The asterisks in part. C of Table- 19 refer to adult populations' of Teredo bartschi of less than 10 per panel. In those cases, failure to find a brooding individual could be due to chance. The decline in population 79

follows the high mortality described in the previous section (4.1),

occuring in March-April. Those surviving fe. male specimens are nearly all brooding in June-August; by September and October, the next generation is producing young.

4.2.4 Plankton Use of a plankton net to search for shipworm larvae was done between 1980-1982. Not all of the results were presented in our quarterly re-ports, because time was needed to sort the preserved plankton samples. A summary of all the data is in Table 20. Larval identifications were made by comparison with laboratory-reared larvae, and by observing which species were settling in the area. In many cases, young shipworm larvae could not be positively identified to species. No larvae were found in June or November of any year.

The density of shipworm larvae fell off quickly as the net was moved from 0-1 meter from the bulkhead area out into the creek or bay. In most ,

sampling episodes, few bivalve larvae were found in the 2-3 meter dis- l tance from shore. This is not to say they were absent, but that their density was too low for them to be picked up in the 2 short tows that were conducted at this distance.

The patchy nature of Teredo bartschi settlement and the species' short migration distances are confirmed in Table 20. The finding of these pediveligers in the water column at all does show that the species swims while seeking wood habitat, and does not have to settle on the wood from which it was released.

Tows taken near the mouth of Oyster Creek (station 10) were usually negative for larvae, indicating that most Teredo bartschi pediveligers probably remained in Oyster Creek. Again, the low probability of captur-ing la rvae with the sampling effort used should be kept in mind. That l some T. bartschi did get to Forked River and Waretown is certain, because they were found in panels there. However, it is probably safe to con-clude that Oyster Creek did not contribute a large number of Teredo larvae (especially T. navalis and Bankia gouldi) to Barnegat Bay during 1980-1982. The situation was likely different in earlier years of ope-I ration of the generating station, when the. effluent was warmer and more often present, and when the. native species as well as two introduced ones were very abundant in Oyster Creek.

In 1980-82, shipworm larvae of all- three species were found only coinci-dent with their respective periods of settlement, despite the presence of adults brooding well-developed larvae at other times (section 4.2.3 80

Table 20 Teredinid Larvae from Plankton Samples Taken 0-1 and 2-3 M from Bulkheads 1980 1981 1982 July Oct. July Oct. Aug. Sept.

0-1 2-3 0-1 2-3 0-1 2-3 0-1 2-3 0-1 2-3 0-1 2-3 M B. gouldi 1 0 0 0 0 **

• O O *

• 0 0 4 0 0 0 0 0 0 0 0 8 0 0 0 0 0 0 0 0 0 0 0 0 10 0 0 0 0 0 0 0 0 0 0 0 0 11 0 0 0 0 0 0 0 0 0 0 0 0 12 0 0 0 0 0 0 0 0 0 0 0 0 14

• 0 0 0 0 0 0 0 T. navalis 1 0 0 0 0 **

• O O O O O O 4 0 0 0 0 0 0 **

• 8

• 0 0 0 0 0

• 0

• 0 0 0 10 0 0 0 0 0 0 0 .0 0 0 0 0 11 0 0 0 0 0 0 ** O O O O O 12 0 0 0 0 0 0 ** O O O O O 14 0 0 0 0 0 0 *- 0 Native sp, I

• 0- 0 0 0 0 0 0 0 0 0 0 4 0 0

• 0 * * *

• 8

• 0

• 0 0 0 0 0 **~ * ~ .

• O' 10 0 0 0 0 0 0 0 0 0 0 0 0 11 0 0 0 0 0 0 0 0 0 0 0' O 12 0 -0 0 0 0 '0 0 0 0- 0

• O-14

• 0 0 0 0 0 0 0 T. Lartschi 4 0 0 0 0 0 0 0 0 0 0 8 0 0 0 0 0 0 0 0- 0 0 0- O' 10 0 0 0 0 0 0 0 0 0 0 0 .0 11 0 0 0 0 ** 0 0 -0 0 0 0 0 12 0 0 ** 0 0 0 0 0 0 0 0 0 14 0 0 0 0 Two plankton town of standard distance were taken at. each posiition.

• 1-10 larvae

• • >10 larvac Native sp. = B. gouldi or T. navalis 81'

above). If a few adult Teredo bartschi released larvae in winter or spring, they have gone unrecorded.

4.3 Growth Heasurement of growth in shipworms was indirect, because destructive methods were used in sampling. Monthly x-ray of a single piece of wood followed by its return to the water proved disruptive to normal growth and was discontinued. Interpretation of growth patterns in teredinids is difficult because growth of the individual specimens is so dependent upon available space in the wood. This crowding factor was demonstrated in Hoagland et al. (~1977), our first quarterly report on this project. It was also illustrated in our third report. The negative correlation of mean size of shipworms from a given panel with the population size in that panel was r2 = .92. Also, settlement times and hence age of indi-vidual specimens are only approximately known and vary within a piece of wood.

Instead of calculating mean sizes for the rest of the data, I have located the largest individual of each species for each month, in cumu-lative and yearly panels. The number of times each station had the largest specimen is recorded in Table 21. Because Teredo hartschi was limited to the thermal effluent and no comparison can be made with other stations, data for it are omitted.

There was a tendency in uncrowded panels for the largest individuals of Bankia gouldi to be in Oyster Creek, with Forked River also often having the largest individuals. There were many exceptions. There was no tendency for the largest specimens of Teredo navalis to be found at any particular station. The species differed greatly in size, with Bankia gouldi > Teredo navalis > T. bartschi. Growth af all species ceased for the winter in about December and began again in April or May, according to size frequency data from cumulative panels both listed and figured in our quarterly reports. Frequently there were young specimens of less than 5 mm that settled in late fall and did not grow further until late spring. These individuals could be misinterpreted as having settled in winter. Evidence from the monthly panels and breeding data (section 4.2) suggest that this was not the case.

A conclusion from the data in Table 21 and the histograms in earlier reports is that accelerated growth of Bankia gouldi did occur in Oyster i

Creek and the mouth of Forked River, despite crowding. Teredo navalis l was probably more affected by crowding because it. settles later in the reproductive season than B. gouldi and it grows slower.

i i

82

Table 21 i Growth Data on Shipworms from Oyster Creek 4

vs. other Stations Below are counts of the number of times each station had the largest specimen

of a given species in cumulative and yearly panels. The plant was operating j at least part of the submergence time of each panel scored. The number of times the species was present at the station is in parentheses. Data are for i 1976-1979, when data for most stations were available.

B. gouldi T. navalis Station 1 3(43) 6(16) 2 0(40) 2(8) 3 0(3) 0(0)

1. 4 6(45) 4(22)

1. 5 4(48) 11(26) 6 1(24) 0(0)

, 7 0(14) 0(0) i

~

1. 8 5(38) 4(17)

• 10 9(32) 1(5)

• 11 8(38) 1(12)

• 12 10(34) 2(16) 14 3(46) 8(20) 15 1(17) 1(4) 16 0(15)- 0(0) i 17 1(16) 5(15) 18 0(4) 4(23) 19 0(5) 1(13)

Pooled Forked River Stations 15(131) = .11 19(65) = .29-Pooled Oyster Creek Stations 27(104) = .26 4(33) = .12 Pooled Other Stations 9(227) = .04 27(99) = .27

• 0yster Creek

1. Forked River, mouth and S. Branch i

83

i 4.4 Wood Destruction The amount of actual wood destruction caused by boring organisms was quantified in the quarterly reports and analysed statistically in this report. Analyses for annual panels (submerged 12 months) are in Table 22; those for cumulative panels are in Table 23. Table 24 gives analysis for a reduced set of stations for which more data were available. A nested analysis of variance was performed on the 2/3 power of percent wood weight loss. The 2/3 power transformation was selected as best meeting two criteria: reduction in dependence of variances on means and reasonable comparability within and across years and stations. This transformation lends the possible interpretation that weight loss is a function of area of the panels damaged by shipworms.

Missing observations arose from various causes, including samples not taken due to ice cover, panels or racks lost, and panels partially or completely lost due to riddling by shipworms. Those missing observations that were riddled panels were assigned an 85% wood-weight loss, a value approximating the weight loss of the most heavily-damaged panels that did remain attached to the racks. Replicates from a single station were averaged before further analysis. Not all stations were studied in all years. The 20 stations were organized as if replicate plots in one of 5 station groups: 1) Oyster Creek (#10, 11, 12, 13); 2) Forked River and its mouth (#4, 5, 6, 8, 9); 3) Bay controls (#1, 2, 14, 15, 16, 17); 4)

Creek controls (#3, 7, 20); and 5) Offshore island controls (#18, 19).

Shipworm colonization was primarily in summer and early fall, and most growth ceased by November when the temperature dropped below 12' C.

Therefore, the cumulative panels collected from November through May should be correlated in damage, having been exposed to the same amount of shipworm attack. Similarly, for annual panels, those collected from November of one year to July of the following year should have similar damage patterns. Hence, these were the data analysed. Other data showing the patterns in shipworm settlement and growth from July to November are in our quarterly reports.

Since the observations within a station-year should be serially corre-lated, the best available approximation to replicate plots was through stations within station groups. Accordingly, dates were nested within stations, and stations were nested within station groups. This procedure follows, in principle, the recommendations of Finney (1982).

Nested analyses of variances, with adjustments for unequal sample sizes as needed, were carried out (e.g. Sokal and Rohlf, 1969, box 10.4). A priori comparisons of creek control versus all other stations and Oyster 64 i

(

Table 22 Nested Analysis of Variance of 2/3 Power of Percent Wood Weight Loss in Annual Panels (Totals may not agree due to rounding.)

A. Collected from November 1977 to July 1978.

Added Source SS df MS Variance F E Component (AVC)

Station group 345.0 4 86.3 -2.007* <1.0 ns Station 1556.2 12 129.7 22.394 36.9 <.001 Date 274.1 78 3.52 3.515 Total 2175.4 94

• By convention, this is assumed to be estimated as 0.

B. Collected from November 1978 to July 1979.

Source SS df MS AVC F g Station group 1762.3 4 440.6 8.817 1.96 ns Station 2559.3 15 170.6 28.952 50.90 <.001 Date 351.6- 105 3.35 3.349 Total 4673.3 124 C. Collected from November 1979 to July 1980.

Source SS df MS AVC F g Station group 2414.0 3 804.7 42.474 187.60 <.001 Station 21.4 5 4.3 0.291 :2.48 .05>P>.025

!. Date 120.4 70 1.72 1.721 Total 2555.8 78 D. Collected from November 1980 to July 1981.

Source SS df MS AVC F. g Station group 335.5 3 111.8 5.081 4.56 .1>P>.05 Station 122.5 5 24.5 2.622 6.94 <

'.001 Date 222.4 63 3.53 3.531 Total 680.4 71 85

Table 22 cont.

Nested Analysis of Variance of 2/3 Power of Percent Wood Weight Loss in Annual Panels (Totals may not agree due to rounding.)

E. Collected from November 1981 to July 1982.

Source SS df MS AVC F g

! Station group 97.8 2 32.6 4.125 3.47 ns Station 43.8 5 8.8 2.295 3.01 .05>P).025 Date 43.7 15 2.91 2.915 Total 185.4 22 f

i l

l 1

i 86

Table 23 Nested Analysis of Variance of 2/3 Power of Percent Wood Weight Loss in Cumulative Panels (Totals may not agree due to rounding. All sampled stations and dates.)

A. Submerged May 1977 and collected November 1977 - May 1978.

Source SS df MS AVC F E Station group 595.5 4 148.9 0.142 1.02 ns Creek control vs. others 172.3 1 172.3 1.22 ns Station 1834.7 13 141.1 21.772 43.58 <.001 Date 314.1 97 3.24 3.238 Total 2744.3 114 1.22 ns B. Submerged May 1978 and collected November 1978 - May 1979.

Source SS df MS AVC F p Station group 2311.0 4 577.8 19.058 4.33 .025>P>.01 Creek control vs. others 1296.3 1 1296.3 9.84 .01>P>.001 Station 1711.9 13 131.7 19.366 31.93 <.001 Date 416.6 101 4.12 4.125

Total 4439.6 118 i

C. Submerged May 1979 and collected November 1979 - May 1980.

Source SS df MS AVC F g I

Station group 1843.4 3 614.5 41.452 35.97 <.001 Creek control i vs. others 1612.6 1 1612.6 97.3 <.001 Station 82.4 5 16.49 2.388 20.44 <.001 Date 41.1 51 0.807 0.807 Total 1966.9 59 D. Submerged May 1980 and collected November 1980 - May 1981.

i Source SS df MS AVC F E l Station group 279.7 3 93.22 3.657 2.44 ns Creek control vs. other 233.0 1 233.0 6.10 .1>P>.05 Station 191.2 5 38.23 4.757 7.75 -<.001 Date 266.3 54 4.93 4.932 Total 737.2 62 87 4

, e - . ~ p - va - e ,m

l Table 23 cont.

I tielted Analysis of Variance of 2/3 Power of Percent Wood Weight Loss in Cumulative Panels E. Submerged May 1981 and collected November 1981 - May-1982.

Source SS df MS AVC F p.

Station group 157.4 3 52.47 0.059 1.015 as Creek Control vs Others 114.8 1 114.76 2.38 ns Station 241.3 5 48.26 7.335 18.41 <.001 Date 128.5 49 2.62 2.621 Total 527.2 57 i

J i

l l

I l

88

I Table 24 Nested Analysis of Variance of 2/3 Power of Percent Wood Weight Loss Cumulative Panels Submerged in May at Stations 1, 4, 5, 8, 10, 11, 12, and 14 (Totals may not agree due to rounding.)

A. Collected in pe-iod November 1977 - May 1978.

Source SS df MS AVC F g Station group 182.4 2 91.2 2.564 1.94 ns j Oyster Creek vs. Forked R. 112.0 1 112.0 2.44 ns Station 236.4 5 47.3 6.426 10.05 <.001 Date 211.7 45 4.70 4.705 Total 630.6 52 B. Collected in period November 1978 - May 1979.

Source SS df MS AVC F E Station group 900.3 2 450.1 23.112 9.86 .025>P>.01 Oyster Creek vs. Forked R. 893.7 893.7 18.60 .01>P).001 Station 234.1 5 46.8 6.134 9.15 <.001 Date 235.3 46 5.12 5.115 Total 1069.6 53 C. Collected in period November 1979 - May 1980 Source' SS df MS AVC F g Station group 229.6 2 114.82 5.611 6.80 .05>P>.025 Oyster Creek vs. Forked R. 226.1 1 226.1 13.78 .025>P>.01 Station 82.4 5 16.49 2.372 18.03 <.001 Date 41.1 45 0.91 0.914 Total 192.3 52 89

s Creek versus Creek control were performed on cumulative panel data. A priori comparisons of Oyster Creek versus Forked River were carried out on reduced data sets in the first three cumulative years; it was apparent from residual sums of squares that such a test would be non-sigaificant in the other years (Table 24).

lieterogeneity of stations within station groups was detected in all 5 years for both annual and cumulative panels. In the second and third years of cumulative panel data (1978-79 and 1979-80), creek control comparisons were significant at the 1% and 0.1% levels, respectively (Table 23). In the same years the Oyster Creek versus Forked River comparisons were significant at the 1% and 2.5% levels, respectively, and Oyster Creek versus creek controls was significant at p <.01 (Table 24).

Average weight losses were greater in Oyster Creek than in Forked River and far greater than in the Creek controls. This significant result suggests an effect of the thermal effluent in Oyster Creek above the e f fect of increased salinity in both Oyster Creek and Forked River, compared to the creek controls.

Further interpretation can be made by examining records of plant outages.

In years with major spring and summer outages, one would not expect to find a significant difference between Oyster Creek and the other sta-tions. In the summer of 1977, there was such an outage, and there was not greater wood loss in Oyster Creek than elsewhere (Tables 22-24, part A).

The yearly panels submerged in 1977-1978 (Table 22B) still showed no significant differences. The outage in 1978 was shorter and occurred in late fall when settlement and growth of shipworms is not affected by the thermal discharge anyway. There was also no major outage in the 1979-1980 period that would have affected shipworm settlement and growth.

Statistical analysis showed significantly more wood damage in Oyster Creek in panels submerged from mid 1978 to mid 1980 and collected from November 1978 to July 1981 (Table 22C and D; Table 23B and C; Table 24B i

and C). There was a very long outage covering the first half of 1980, coincident with the lack of significant shipworm damage in both Oyster Creek and Forked River compared with creek controls (Table 23D). In 1981, there was a slow recovery of shipworms in Oyster Creek from the previous dieback, coupled with outages in spring and fall. Statistical results were not significantly different in Oyster Creek (Table 23E). In 1982, a very long winter-spring outage appeared to eliminate subtrcpical shipworms from Oyster Creek entirely. In summary, the years when there was significantly greater damage to wood in Oyster Creek are the years which had the greatest impact of the thermal effluent. The statistical methods used in this analysis are conservative, minimizing the number of cases where statistical significance is found.

I l

I 90 i

l l

1 4.5 Wood Penetration The results of experiments to test settlement preferences and growth patterns in large pieces of wood extending from the mudline to the water surface were first given in our reports NUREG/CR-1939 vol. 3, p. 23, and NUREG/CR-2727 vol. 1. Stakes submerged only 4 months contained very few shipworms. It appeared that there might be a tendency for Teredo bart-schi to settle on the lee side and near the mudline, whereas there was no preferred settlement pattern for T. navalis and Bankia gouldi.

Stakes removed one year later were naturally more heavily infested, but were not riddled and individuals could still be traced in x-rays. It was evident that there was not a tendency for Teredo bartschi or any other species to settle on the lee side or at the mudline. There was, however, a strong tendency for all species to grow downward, for T. bartschi to be clustered, and for the other species to be scattered. The results are pooled for each collect. ion date and summarized below ('lable 25).

Table 25 Settlement Patterns, Teredinid Species Borehole Settlement. Growth Within 10 cm of mudline i currents lee up down yes n o, 1980 B. gouldi 9 7 3 12 1 15 T. navalis 3 6 2 7 3 6 T. bartschi 5 9 3 11 13 1 1981 B. gouldi 8 4 1 11 3 9 T. navalis 4 3 2 5 1 6 i T. bartschi 53 26 15 35 0 74 l

l i

91

! 4.6 Physiological Ecology l

l

[ The results of physiological experiments can best be summarized in a table showing temperature and salinity tolerances of the three teredinids under study. Dashes indicate that no data were obtainable. The values in the table are for animals taken from Barnegat Bay or Oyster Creek, maintained at approximately 24 1 3* C and 23 i 1*/oo salinity in the laboratory. Results with other stock could differ.

Values in Table 26 are those under which at least half of the test ani-mais altered their behavior. Most experiments were performed three times. I give the range observed, if any, as well as the mean. These values may differ slightly from earlier results published in our quar-terly reports, because several experiments were replicated during fall, 1982. Optimal temperature and salinity for growth of Teredo bartschi were determined from a long-term experiment in which all combinations of 3 temperatures and 3 salinities were established as experimental con-ditions for groups of post-settlement juveniles. The same experiment yielded data on optimal and possible conditions for maturation and spawn-ing.

Salinity tolerance limits were similar for adults of all three species.

More than 50% of the specimens were active over the range 7-45 /oo at

~24' C in experiments lasting 60 days. However, optimal salinity for Teredo bartschi was slightly lower than for the native species. Spawning of larvae occurred at lower salinity, also.

Pediveligers of both Teredo species had greater individual variability than the adults in their response to salinity. Pediveligers tolerated a lower maximum salinity than adults, but the minimum values were the same.

Tolerances for T. navalis veligers were the same as for pediveligers described in Table 26. Pediveligers of T. navalis were active over

~6-31*/ o, while those of T. bartschi were active over ~8-35*/ . In both species, signs of severe osmotic stress occurred at 5 /oo.

Optimal salinity for pediveligers of T. bartschi was complicated by behavioral changes. At 20-25 /oo, pediveligers swam actively, while at 13-15 /oo, they exhibited boring activity or swam near the bottom. This change was observed in three separate experiments. It suggests that this species begins to search for wood when it reaches moderate-to-low salinity areas of its natural mangrove habitat.

l Both adults and juveniles of all species begin to show behavioral signs l of osmotic stress below 10*/oo. Salinity in tidal creeks of Barnegat Bay is frequently below 10*/ , even in the portions below Route 9 (Figure 6; 92

?

l l

l

Table 26 Physical Tolerances of Teredinids from Oyster Creek and Barnegat Bay (Salinity = */oo; Temperature = *C)

7. bartschi T. navalis B. gouldi Physiological Condition Adult Pediveligers Adult Pediveligers Adult Upper salinity, cease activity 45(43-46) 35(26-40) 46(45-47) 31(27-40) 46(45-46)

Lower salinity, cease activity 6(5-9) 8(4-10) 7(5-10) 6(5-7) 6(5-8)

Lower salinity, mortality '

4(3-5) 5(3-7) 4(3-5) 4 4(3-5)

Optimum salinity 22 20-25, swim >251 -

>25 13-15, boring Spawning range (*/oo) 6-40 -

10-40 - -

1 1

, Optimal growth, temp / sal. 30*, 14*/ or 20*, 22*/ . -

25*, 30*/ -

w . Optimal spawning temp./ sal. 20*, 22 /.. - -

~25*, ~22*/..

Upper lethal temp. 35(34-35) 32 30(30-31) 31(29-31) 30(29-30)

~ Temp. range, growth 14-30 - - - - i Lower temp., cease activity 15(12-17) 18(16-20)2 4(3-9) 12(8-19) 5(4-9)

Lower temp., mortality 6(3-13) 5 0 -

0(0 to -1)

Spawning temp.,' range 16-30 -

10-25 -

10-27 Barnegat Bay - Oyster Creek Salinity range 7.5-28 7.5-30*/ . 7.5-30*/ .

Temperature range 13 -37.2 0-31 0-31 2

Culliney, 1975 8 Can be 0 when plant is down.

2 100% inactivity

Table 27). Although tb three teredinids appear able to withstand much higher salinities than they experience under normal conditions, they do live close to their lower salinity limits and salinity is a factor that limits their ranges in the tidal creeks.

The temperature ranges for Teredo navalis and Bankia gouldi were identi-cal (0-30 C), while the range for Teredo bartschi was shifted about 5 C higher (6-35 C). Activity ranges for pediveligers were slightly nar-rower than their adult counterparts. Comparing these laboratory values with field data (Table 28, Figure 5) two interesting facts emerge.

First, T. navalis and B. gouldi must live close to their upper tempera- j ture limits during summer months. In Oyster Creek, the upper limit is reached, or slightly exceeded, but for short periods. However, the natural water circulation in the field undoubtedly allows for better survival at higher temperatures than laboratory results suggest, so laboratory values are on the low side. Secondly, in winter, even in the thermal effluent, the water temperature falls below the minimum for T.

bartschi. Indeed, heavy mortality did occur every winter for this spe-cies, leading me to suspect that strong selection for lower temperature tolerance was occuring. Another possibility was that there was an addi-tional point source of heat entering Oyster Creek, raising the tempera-ture locally. Warm water was found to be entering Oyster Creek from homes near station 12, but the winter temperature at that point was still only 2-3* C, not appreciably above the temperature of the effluent.

Our temperature and salinity studies confirmed that Teredo bartschi, unlike the two native species, was a tropical to semi-tropical species, living naturally under estuarine conditions. Our results for Teredo navalis are close to those of Blum (1922), who found an optimal salinity of 6-8 /oo in San Francisco. Although variation in results is expected under different acclimation conditions, all species were treated alike and one can have confidence in the comparative aspect of these experi-ments. The optimal growth and breeding temperature and salinity for the Oyster Creek specimens of T. bartschi was very close to the early summer and fall conditions in the field, and to the acclimation conditions. The results in Table 26 will be absorbed into an analysis of niche differ-ences and competitive overlap presented in the general discussion section of tl.is report.

Simple experiments designed to test the ability of adult shipworm to j tolerate silt gave results of little value. Although shipworms withdrew their siphons initially, they came out again almost immediately and remained out even if the water remained highly turbid. A more quanti-tative experiment is needed to correlate exact levels of turbidity with l filtration efficiency. The responses of the three species of shipworms to silt were indistinguishable.

94 l

i I

1 i

Wood preference experiments using only Teredo bartschi gave surprising results. The pediveligers settled preferentially on wood not previously used in Oyster Creek and avoided wood that had been taken from the field.

They were not attracted any more strongly to wood containing adults of the same species. Clustering of the pediveligers as they settled on wood occurred in yearly panels containing adults, but also on cumulative panels and large stakes without adults, as described in the previous section on wood penetration. I believe that settlement of pediveligers of T. bartschi probably occurs in clusters because (a) their dispersal powers and prospensity to disperse are low; (b) they are seeking a favor-able microenvironment for attachment and boring.

Table 27 Annual Minimum Salinity Records, by Station 1976 1977 1978 1979 1980 1981 1982 Station 1 14.0 6.2* 10.0* 9.0* 8.0* 8.0* 3.0*

2 10.0* 10.0* 10.0* 5.0*

3 16.3 12.0 5.5* 2.0* 4.0* 7.0* 2.0*

4 24.0 16.5 16.0 17.0 18.0 23.0 20.0 5 24.0 16.4 16.6 15.5 19.3 23.0 20.0 6 19.5 14.9 16.0 15.0 22.0 7 9.5* 7.4* 3.8* 2.0*

8 24.0 16.9 18.0 17.0 16.0 22.0 21.0 9 13.9 5.0*# 15.0 10 23.5 13.5 16.2 10.0* 16.0 21.0 18.0 11 23.0 13.3 16.2 12.0 16.0 21.0 21.0 12 23.2 12.8 15.1 12.0 12.5 20.0 21.0 13 24.0 12.0 12.0 14 20.5 18.9 15.0 16.0 14.0 15.0 23.5 15 21.5 16.9 18.0 18.0 16.0 16 20.5 17.3 21.0 17 19.3 16.2 16.0 11.0#

18 19.7 25.5 17.0 19 20.5 15.0 16.0 20 2.0* 5.0*

• 0smotic stress for teredinids

1. Surface water from local runoff Stations 10-13 are in Oyster Creek 95 J

Table 28 Annual Maximum and Minimum Temperatures, by Station 1976 1977 1978 1979 1980 1981 1982 Station Max./ Min. Max./ Min. Max./ Min. Max./ Min. Max./ Min. Max./ Min. Max./ Min.

1 24.8/0.0 27.0/0.2 24.4/1.0 27.0/-1.7 29.5/-0.5 25.6/-0.5 26.5/2.0 2 25.5/-0.5 29.0/0.1 25.3/1.0 27.2/-0.6 3 27.5/-0.5 31.0/-0.5 28.3/3.0 28.9/-0.8 31.0/-0.5 27.8/* 29.5/3.0 1 4 27.3/1.5 28.0/0.0 26.1/-1.3 28.0/-1.1 29.5/-1.0 26.1/-1.5 27.0/2.0 5 27.0/2.0 27.5/0.3 26.1/-1.0 30.0/-1.7 30.5/-1.0 27.2/-1.5 28.0/2.5 6 26.5/2.0 28.5/0.6 26.6/2.1 */0.8 24.4/*

7 26.0/-1.0 28.0/0.7 26.1/0.4 27.8/-0.6 8 28.0/2.5 28.0/1.8 27.2/-0.5 30.0/-1.1 31.0/-2.0 28.9/-1.5 28.8/1.5 9

• 28.0/6.8 26.6/0.0 29.5/-0.6

$ 10 30.0/4.0 31.5/3.5 30.0/3.0 33.0/1.1 31.5/0.0 28.9/0.5 30.0/2.0 11 30.5/3.0 31.0/3.5 30.5/4.0 33.0/3.3 32.5/0.0 28.9/0.0 30.5/2.0 12 31.0/5.0 32.5/4.9 30.0/4.0 34.0/2.2 33.0/0.0 28.9/-1.0 30.5/2.5 13

• 21.4/* 29.4/6.1 29.9/4.4 14 26.0/2.0 29.0/1.2 26.1/1.0 27.8/-1.1 28.2/0.0 24.4/-2.0 26.0/*

29.5/0.3 26.0/1.0 *

1.5 26.0/0.0 16 26.0/0.0 29.5/0.0. 26.1/*

• 17 26.2/-1.5 28.0/0.0 25.5/-1.0 */-1.7 18

• 25.5/* 20.8/-1.0 26.0/-1.7 19

• 27.0/* 23.3/-1.0 25.7/-1.7 20 *

• 23.9/* 26.2/0.0

• Data missing for critical months Blanks = station discontinued. Stations 10-13 are in Oyster Creek

- - .. ~ . . . ..

5. FOULING COMMUNITY i

j 5.1 Comparison of Stations and Years

The similarity of attached fouling communities at the various stations was analysed by computing the overlap in species composition expressed as percent cover

Overlap =[1 min (Xg, Xik), where Y q = the percent cover averaged over in-and outside panel surfaces and then averaged over stations within a group, for taxon i and station group j ; X.k= the aver-

aged percent cover for taxon i and station group k. The t'axa were not pooled for this analysis, and the presence of scattered rare species lowered the overlap values.

Panels submerged and removed in the same month were compared. Each year was analysed separately. Because the fouling community is well-developed by August and reaches peak density in November, these two removal times were chosen to represent the full data set, which is too large and cum-bersome to present ~in full detail. Month-to-month development of the fouling community is of theoretical interest, but it is not of direct relevance to the the rmal effluent problem, and is not analysed in this report. It will be covered in a separate paper.

l Station groups are given in Table 29. The bay controls were split into groups north and south of the Oyster Creek - Forked River area. This was done on the basis of a known disjunction in the ranges of the isopod l Limnoria tripunctata and the bryozoan Bugula turrita, both of which were common at stations 14-17 but absent at stations north of Oyster Creek.

In August, annual panels were least similar between the creek controls l

and all other comparisons (Table 29). In 1977 and 1979, Oyster Creek was a bit more similar to the creek controls than were most of the other station groups. Forked River tended to be more similar .to the bay con-trols than to Oyster Creek, a signficant finding. The island stations-were quite distinct from the other station grcups. The overlap values varied from year to year, being much higher in 1979 than in 1978 and_

1977.

The August cumulative panels also revealed the distinctiveness ' of the creek controls (Table 30). As in the annual data, the distinction was less in 1979 when overlap values were higher overall, but the Oyster Creek - creek control comparison gave a larger overlap value than other creek control comparisons in 3 of 4 years. The. Forked River'- Oyster Creek comparison was highly variable r from year to year. In ~ 1976 and 97

Table 29 Total Overlap by Station Group

• for Averaged Percent Cover, Attached Fouling, Annual Panels Collected in August BCS CC FR OC IS 4

1977 BCN 79.1 11.2 79.3 66.5 BCS 7.0 66.8 70.2 CC 15.0 39.5

'FR 68.2 1978 BCN 27.0 19.7 32.6 26.0 12.8 BCS 14.2 73.7 17.4 25.2 CC 12.3 11.1 25.5 FR 26.0 10.4 OC 4.7 1979 BCN 94.5 24.2 124.2 74.2 7.2 BCS 67.5 118.7 110.7. 54.2

~CC 27.0 65.7' 46.0 FR 77.0 38.3 OC 58.0

• BCN (bay controls - north) = 1, 2 BCS (bay controls - south) = 14, 15, 16, 17 CC (creek controls) = 3, 7, [20]

FR (Forked River) = 4, 5, 6, 8, [9]

OC (Oyster Creek).= 10, 11, 12,_[13]

IS (Island controls) = 18, 19 Bracketed Stations were not regularly included in fouling studies.

l 98 9

w

Table 30 Total Overlap by Station Group for Averaged Percent Cover, Attached Fouling, Cumulative Panels Collected in August BCS CC FR OC IS 1976 BCN 34.0 2.0 33.1 1.0 BCS 11.6 41.6 7.3 CC 4.5 21.7 FR 5.1 1977 BCN 68.4 28.7 95.1 50.2 64.0 BCS 14.6 86.1 39.7 86.7 CC 21.1 34.7 19.2 FR 57.8 84.1 OC 56.6 1978 BCN 11.0 9.8 13.4 1.2 13.0 BCS 5.5 61.2 10.5 -27.0 10.2 CC 13.0 12.0 FR 14.9 33.5 OC 33.3 1979 BCN 89.0 84.0 53.8 99.8 68.0 BCS 53.8 43.5 103.7 58.2 CC 32.0 60.3 55.7 FR 56.2. 59.6 63.8 Station groups are as in Table 29.

99 l

'1

l 1977, Forked River was more similar to the two bay control groups than to )

Oyster Creek. In 1978 and 1979, only one bay control group was more l

, similar to Forked River than to Oyster Creek. The variability within Oyster Creek from year to year can be seen by comparing the Oyster Creek columns in Table 30 from year to year. In 1976 and 1978, Oyster Creek

, showed little overlap with the bay controls. In 1977, there was moderate overlap, and in 1979 overlap was high.

Data were unavailable for November of 1979, because sampling ended in September. Between August and November, in 1976 and 1977, cumulative

panels at the different stations became more similar (Table 31). Espe-cially Oyster Creek's similarity to the creek controls was greater in fall than in summer. This trend was not observable in 1978. In 1976, j Oyster Creek was most similar to the creek controls, followed by Forked

! River and the bay controls. In 1977, the pattern was almost the same I

except the overlap value for Forked River and the northern bay controls were about the same. In 1978, all overlap values rere low, but Oyster '

Creek showed greatest affinity with Forked River.

Table 32 compares yearly variation within the station groups. The lowest yea r--yea r overlap values were in Oyster Creek in 8 of the 12 year-year comparisons. The greatest similarity from year to year was in creek controls (6 comparisons), island controls (twice, but not studied in all years), and northern bay controls (4 comparisons). Therefore an initial I hypothesis of the study, that the fouling community in Oyster Creek might l be less stable than at control stations, appears to be supported. Oyster Creek was less stable than Forked River, showing that special factors in the discharge area such as the heated effluent (high maximum tempera-ture), dredging of Oyster Creek, and irregular recruitment of larvae due to mechanical destruction in the plant intake and bypass systems may have been responsible, j The overall effect of the generating station with its outages is a less stable fouling community in Oyster Creek, but the day-to-day effect is more obscure. It is difficult to compare directly the pumping rates and AT's in Oyster Creek and Forked River with the composition and stability of the fouling community at any o'ne time. This is due to the lag times between cause and effect, and the fact that pumping did continue when the

. AT was absent.

5.2 Interaction with Boring Organisma l The percent cover for each of seven taxa of attached fouling organisms l was correlated with the abundances of'each species of shipworm. The full

( data set was the cumulative and yearly panels at all stations except 9, 1 l

i 100

Table 31 Total Overlap by Station Group for Averaged Percent Cover, Attached Fouling, Cumulative Panels Collected in November BCS CC FR' OC IS 1976 BCN 56.0 9.5 74.6 6.5 BCS 28.6 70.9 23.4 CC 36.9 159.8 FR 31.7 1977 BCN 99.5 35.5~ 104.2 63.2 97.7 BCS 14.7 79.5 46.5 89.9 CC 28.5 165.1 26.0 FR 61.1 88.5 OC 54.6 1978 BCN 10.5 8.5 47.8 15.7 12.0 BCS 14.5 23.1 15.8. 63.5 CC 11.5 12.4 15.0 FR 26.1 21.0 OC 16.8 Station groups are as is Table 29.

l l

101-y -

Table 32 Total Overlap of Averaged Percent Cover Comparing Years by Station Group A. Annual Panels Collected in August Station Group 77-78 77-79 78-79 BCN 40.0 46.8 58.8 BCS 43.8 b 34.6 b 39.2 CC 47.2 155.0 44.0 FR 41.0 8 50.9 8 62.5 OC 19.8 20.7 15.0*b IS 126.3 B. Cumulative Panels Collected in August

)

76-77 76-78 76-79 77-78 77-79 78-79 8 b 8 BCN 38.2 32.7 1.7 48.0 19.5 8 29.0 BCS 26.9 b 13.4 6.9 b 13.8 7.9 b 35.8 CC 76.8 32.3 a 78.2 33.8 158.2 55.8 FR 51.1 8 2.l 6.9 8 34.2 a 38.9 52.3 OC 6.5 20.2 1.7 5.8 31.7 31.8 IS 43.0 68.0 109.3 C. Cumulative Panels Collected in November 76-77 76-78 77-78 b b BCN 109.8 39.8 44.8 BCS 34.4* 32.4 51.6 D CC 78.0 31.5 113.0 FR 76.1 31.4 49.1 8

OC 65.8 0.5" 22.8 IS 84.0

• b Smallest verlaP for the year-year comparison.

Greatest overlap for the year-year _ comparison.

102 i%

_ __ _ ._ = .- - - _ - -. -

13, and 20, for which little fouling data were available. The raw abun- l

! dance data and the logarithm of (abundance +1) were both used. Addi-  :

tionally, various subsets of the full data set were examined: yearly t

! panels, cumulative panels, cumulative panels collected in June-October, and all panels except those from the creek and island control stations.

l The latter was to remove effects of salinity.

The seven taxa chosen were those most likely, based on their life forms, to interfere with teredinid settling and growth, and those with distri-butions that seemed to be related in some way to the thermal effluent.

They were Botryllus schlosseri (a colonial gelatinous tunicate), Hydr-oldes dianthus (an encrusting calcareous tube-building polychaete), Mer-cierella enigmatica (also a calcareous t.ube-building polychaete but i introduced to Barnegat Bay), Limnoria tripunctata (a wood-boring isopod),

i Haliclona loosanoiti (a yellow sponge), Molgula manhattensis (a solitary tunicate), and Balanus eburneus (a large, common barnacle). The last three species showed no correlations with teredinid settlement and are excluded from furthet analysis.

Individual correlation coefficients may be judged significant at the 95%

level by the usual tables (Table 33). However, departures from normality and the large number of correlations examined would suggest against 4 regarding the observed significance levels as precise. Since some corre-lations are stable over all examined subsets of the data, these may be more worthy of interpretation than those which appear significant in only a few subsets of the data. Comparisons that yielded no significant results are not included in Table 33.

Hydroides dianthus is positively correlated with Bankia gouldi, uncorre-lated with Teredo navalis, and negatively correlated with T. bartschi.

The negative correlation comes about because H. dianthus was relatively scarce in Oyster Creek. These correlations do not suggest that the polychaete interferes with teredinid sett.lement or survival. Rather, there is a common factor contributing to the success of B. gouldi and H.

dianthus in some places, and T. bartschi in others. Both B. gouldi and

, H. dianthus are rare on Long Beach Island where salinity is high. But even excluding the island stations, a positive correlation remains.

Botryllus schlosseri likewise has a negative correlation with Teredo bartschi and a positive correlation with Bankia gouldi. Because it is unlikely that the int.roduced shipworm could interfere with the settlement of either Botryllus or Hydroides, common environmental factors are prob-ably causing the correlations. One possibility is that the entry of larvae of B. schlosseri and Hydroides dianthus into Oyster Creek is neg-atively affected by the power plant water intake system.

103

Table 33 ,

Correlation Coefficients for Percent Cover of Selected Fouling Organisms with Teredinid Species Abundance A dash indicates that the correlation was not computed. A star indicates signficance at the 95% level.

T. battachi B. gouldi Abundance log (Abundance + 1) Abundance Log (Abundance +1)

A. HJd roides dianthus All dat.2 .139* -

.140* -

Yearly panels .151* -

.083 -

Cumulative panels .136* .206* .168* .143*

Cumulative, June.-Oct. -

.236* -

.066 Excluding creek island controls .180* .283* .094* .044 B. Botz1J11us schlosseri All data .073* -

.120* -

g g Yearly panels .073 -

.131* -

Cumulative panels .077 .073 .112* .226*

Cumulative, Jun.-Oct. -

.099 - .165*

Excluding creek & .089* .078* .087* .207*

island controls C. Mercierella enigmatica All data .003 -

Yearly panels .007 -

Cumulative panels .022 .106*

Cumulative, Jun.-Oct. -

.169*

Excluding creek & .006 .138*

island controls D. Linnaria tripunctata T. navalis All data .005 -

Yearly panels .002 -

Cumulative panels .004 .029 Cumulative, Jun.-Oct.

.177*

Excluding creek & .082* .091*

islar.d controls

Mercierella enigmatica is a polychaete introduced into ' 'o rked River, Stout's Creek, and the mouth of Oyster Creek (Hoagland and Turner, 1980).

The positive correlations in Table 33 with Teredo bartschi using log values must be counterposed against the lack of correlations using the raw abundance data. The positive correlations are due to the presence of both taxa in Forked River (albeit rarely) and the absence of both taxa at most other sites. Had N. enigmatica been found with regularity in Oyster Creek, and had it been found there first, one could correlate its pre-sence with the operation of the generating station. As it is, the evi-dence for such a correlation is weak.

Several authors have suggested a negative correlation between Limnoria spp. and shipworms (Nagabhushanam, 1960). There was a trivial negative correlation between L. tripunctata and T. bartschi in that the isopod was restricted by unknown factors to Waretown and to the south where T.

bartschi did not occur. But there were a contradictory mixture of posi-tive and negative correlations between T. navalls and L. tripunctata.

From the data I have, there is not good evidence of interference compe-tition between Limnoria and teredinids, although the possibility exists.

5.3 Individual Species Distribution Patterns Table 34 condenses data on the monthly organisms on wooden panels submerged one month. Taxa included are those that were found at more than one station group more than once in every year, occupied more than 10% of the space on at least one panel per year, and were positively identified to the species level throughout the study. Among the mobile species, only those that tend to remain with a substrate were considered, thus omitting species such as predatory mollusks and most predatory polychaetes. Only eggs and juveniles of the mobile species were included i in Table 34. '

Of 23 species, those that showed an earlier settlement period in Oyster Creek than elsewhere were Balanus eburneus, Barentsia sp.,

Aeverillia armata, Diadumene leucolena, and the algae Enteromorpha intes-tinalis and Polysiphonia harveyi. Barentsia ceased settlement in Oyster Creek during the period of warmest water temperature. A few . species settled everywhere all year long, but most had more limited settlement periods concentrated in summer. There were species that settled pri-marily in fall and/or winter, such as some species of Polysiphonia, Eudendrium, Balanus, and Corophium. Athough a similar species settled every year, it was not the same species.

Table 34 combines data from all three years, hence its record of settlement exceeds the settlement period in any one year._ Neverthless, vitually all species settled over at least three months.

105

. . _ , .-.i..

r- . .. .

Table 34 Settlement of Some Major Fouling Organisms l MONTilS l

Attached Species J F M A M J J A S 0 N D t

Balanus eburneus + + * * *

• x x Barentsia sp. + * *

• x x x x *

• Botryllus schlosseri x x x x

• x x x x Bugula turrita x x x x campanularia sp. * * *

• x n * *

• x x Averi111a annata + * * * * * * * *

• Diadumene lucolena + x * * *

• x +

Electra sp. * * + * * * * * * * *

• Halicolona loosanoffi * * * * +

Hydroides dianthus

• x * * * * *

• x x Mercierella enigmatica x x

• Microciona prolifera x x x x x Molgula manhattensis x

• x

• x * * * *

• x Sabella microphthalma x +

• x + * * * + x Mobile species Brania clavata x x * * * *

• x Doridella obscura

• x x

• x x * *

• Limnoria sp. x x x x x x x x Microdeutopus gry110talpa

• x x * * * * * * * *

• Nereis succinea * * * * * * * *

• Polydora ligni * * * * * * * * * * *

• stenothoe minuta x x x x

• x Algae Enteromorpha intestinalis + + * *' * * * * * +

Polysiphonia harveyi + + * * * * * * *

• Key

+ Settled in Oyster Creek l x Settled elsewhere

• Settled both in Oyster Creek and elsewhere j

- Peak settlement i l

l .106' i

t

l

6. GENERAL DISCUSSION l 6.1 Interpretation of Results (1976-1982)

I The patterns of shipworm abundance, distribution, and reproduction all I show a distinct influence of the Oyster Creek Nuclear Generating Station, 1

particularly on Teredo bartschi. This influence is best seen in Table l 11, which summarizes the pattern of plant' operations and its effects on 4

shipworms. A clear example is the late settlement of T. bartschi in 1980 after a station outage. If one were to use years as replicates without considering plant operations as has been done by others, one could con-

clude erroneously that there was no relationship between the power plant

{ and shipworm outbreaks.

I The ANOVA statistics in this report, using stations as replicates and an 1

0.05 level of significance, underestimate the number of cases where there ,

is a real biological difference between Oyster Creek, Forked River, creek controls, and bay controls. This is because there is high within-and-l between-station variance, within a station group. Shipworms, especially Teredo bartschi, are patchy in their settlement. The stations even a few yards apart had different conditions that could not be foreseen a priori.

l The patchy presence of shipworms in Oyster Creek compared with the very

) ra re occurrence in creek cont rols may not reach statistical signficance at the 0.05 level, but it is biologically different, for it represents a different pattern of settlement and damage. The comparison is often that of 0-1 versus 0-10 or more individuals per panel in the creek controls and Oyster Creek, respectively. The raw data in our quaterly reports should be examined to appreciate this point fully.

For example, while there is no doubt that Teredo bartschi was distributed l according to the thermal effluent (it was never found outside the limits

( of the effluent), the species was rare at some sites well within the-l effluent. There are good biological reasons for the distribution. The currents were too strong at stations 9 and 13 at the intake and outflow, respectively. Chlorination may have been a factor at station 13 because chlorine is known to be toxic to invertebraten and J. C. P. and L. dis-charges chlorine near station 13 (Roche, personal communication). De-spite their presence in the water, very few boring or fouling organisms could settle at these stations. The 1976-1932 data on settlement of both boring and fouling organisms is consistent with the hypothesis of Turner (1971) that larvae entered Oyster Creek from Forked River and particu-larly the by pass channel of the plant. Stations 11'and 12 in Oyster Creek were apparently optimal in temperature, salinity, current regime, and water quality for teredinids and many kinds of fouling organisms.

Station 10 near the mouth of Oyster Creek had a lower temperature and ice 107

i l

l in some winters but more importantly, was in a backwater area, and few l shipworm larvae settled there.

Similarly, there was a large difference between the " replicate" stations chosen on Long Beach Island, stations 18 and 19. Station 18 was exposed to the currents near Barnegat Light, while station 19 was high up in an embayment in a polluted boat marina. Many shipworms settled but died at station 19. Unfortunately, we had no other stations in the area to replicate the conditions at station 18. Station 2 on a point of land at the mouth of Cedar Creek had good water circulation and like stations 18, 11 and 12, was an excellent habitat for shipworms. The greatest surprise of this study was the finding that shipworms did best in areas of high water flow, as long as the flow was not of the scouring sort that occurred at stations 9 and 13.

It is important to analyze the within-station group variance as done above, rather than to dismiss the results as not showing any significant differences. Even with the high variances described above, there were many cases where Oyster Creek had significantly more shipworm damage than creek controls, coinciding with long plant operating periods.

The physical data in section 3 aids in the interpretation of the biolo-gical data, by showing what was theoretically possible in the way of biological growth. We see that there was sufficient wood in Oyster Creek to maintain a breeding shipworm population. Weather could not have caused the patterns seen in boring and fouling organisms. Silt, though heavy in Oyster Creek and parts of Forked River as a result of plant operations, probably did not inhibit boring and fouling organisms except when Oyster Creek was dredged and anoxic mud was deposited on the panels.

The really important factors were temperature range, salinity, outages, and water flow data ... all were consistent and correlated with shipworm settlement times, shipworm physiological data, and abundance data.

Also consistent were the various studies of reproduction, indicating a highly seasonal production and settlement of larvae even in the thermal effluent. The gonad and brooding studies did not show a conspicuous early development and release of larvae of the native species in Oyster Creek, nor did the plankton and seasonal settlement studies show early settlement in Oyster Creek or adjacent areas. The number of larvae released in Oyster Creek and the mouth of Forked River was high compared with other inner bay stations. There was, however, no strong evidence that Oyster Creek served as a breeding ground for any areas beyond Forked River and occassionally, Waretown.

1 108

The laboratory studies of physiological tolerances verified the assump-tion that Teredo bartschi was a warm-water species, compared with T.

navalis and Bankia gouldi. The lab data explained why shipworms did not breed in areas with low salinity such as Stout'r, Creek, the middle branch of Forked River, and the area of Cedar Creek above its mouth. The only

! puzzle is the survival of any T. bartschi in winter, because in the j laboratory virtually all specimens died at higher temperatures than those  !

l winter temperatures in Oyster Creek, even when there was a thermal efflu-l ent. One answer is that. the laboratory results give conservative sur-vival ranges because conditions besides the experimental ones are pro-bably not optimal. Additionally, the sample size in the actual field case is larger and most individuals did die in winter and early snring.

The survivors probably represent the very real process of natural selec-tion of the few heartiest individuals.

6.2 Early Physical Data (1969-1976) l Very little information about Oyster Creek and Forked River are available for the period of time prior to 1969, when the Oyster Creek Nuclear Generating Station began operating. It is said that the section of Oyster Creek from U.S. Route 9 west was freshwater. Some pH data, where pH < 7.0, suggests thot freshwater existed at least as far down Oyster Creek as Route 9. The tiu.1 range in the inner portion of Barnegat Bay around Oyster Creek is only 0.6-0.7 ft, whereas at Barnegat Light on Long Beach Island, it is 3.1-3.8 ft. Quoting from the J.C.P. & L. 316 (a) &

(b) Demonstration text on Oyster Creek and Forked River Nuclear Generat-ing Stations, p. 1-3 (1978):

" Prior to the construction of OCNGS, Oyster Creek and the South Branch of Forked River were characteristic of other low flow, brack-f ish to freshwater creeks with tidal influence limited to a rela- ,

tively small reach near Barnegat Bay. Water quality and aquatic life were characteristic of acidic streams in the New Jersey Pine Barrens area and were relatively poor in quality because of low flow, low pH and anaerobic conditions.

The construction of the intake and discharge canals for OCNGS al-tered Oyster Creek and the South Branch of Forked River by the i videning and deepening of the existing stream beds and the creation of new stream channels. The salinity levels in portions of the creeks which had been brackish to freshwater were changed to higher salinities more characteristic of the bay. The South Branch of Forked River, which serves as the intake canal (Figure 1.1-3), no longer has its flow in the lower reach dependent upon tide, but instead flows toward the OCNGS whenever the station is operating.

109

From the discharge canal, water flows away from OCNGS toward the bay. The velocities in both canals were increased by the pumping of water by OCNGS. Water quality is generally improved since OCNGS began operation, with lower total coliform bacteria counts and higher dissolved oxygen measurements. Along with improved water quality, the aquat.ic community has developed and is more diverse and dense, having a character similar to that found in the bay."

We do not know if Oyster Creek was anaerobic below Route 9 prior to 1969, but other tidal creeks such as Stout's Creek, Cedar Creek, and Potter's Creek are not. J.C.P. & L.'s use of the term " improved water quality" is misleading. No data on coliform bacteria are presented. While the

" aquatic community" is more diverse, this is due to its change from being a fresh to brackish water community to being a moderate-salinity bay community. It is j us t. this change that has brought in the numerous boring and fouling nuisance species described in this report. One can conclude from the above quote that J.C.P. & L. brought about the physical changes that allow boring and fouling organisms to thrive where they were formerly excluded by low salinity (and perhaps low 02 )-

Woodward-Clyde (1975) and Roche (in J.C.P. & L., 1978), in describing the thermal plume behavior, admit t.ha t recirculation of the thermal plume to the mouth of Forked River occurs frequently. The data in this report and the data of Turner (1971-1976, unpublished reports) both show a AT of 1-3 C at the mouth of Forked River more than 25% of the time.

Turner's 1971-1976 temperature data is summarized in Table 35. The AT in these early years was much higher than af ter 1976, because the plant ran fewer dilution pumps (especially in winter). The reduced AT likely did mitigate shipworm damage after 1976, but because so many factors changed at that. time, it is not possible to assign credit to any one change.

Other physical changes were very cold winters, removal of wood from Oyster Creek, prolonged outages of the generating station, and the dredging of Oyster Creek.

Table 36 presents the monthly salinities in Oycter Creek, Barnegat Bay, and creek control stations as reported by Turner. The only bay control station during 1971-1973 was station 1, Holly Park, which is often heavily influenced by runoff from Potter's Creek and even Tom's River.

The most significant factors to note are that while salinity at the creek control stations was oftep <10'/. and therefore stressful to shipworms, only once was a salinity <10*/ . recorded ir. Oyster Creek. Turner's salinity data are consistent with the later data.

110

Table 35 f Monthly Temperature, in 'C, 1971-1976 Oyster Creek Bay Controls AT Plant off 4

i l 1971 Oct.* 19.0 18.0 none x l Nov. 11.0 13.0 none x Dec. 17.5 8.5 9.0 1972 Jan. 14.2 2.5 11.7 Feb. 16.8 5.1 11.7 i

Har. 11.5 5.0 6.5 4

Apr. 17.3 12.1 5.2 May 16.2 -

none x Jun. - - -

x Jul. 35.0 28.9 6.1 Aug. 28.0 23.5 4.5 Sep. 32.0 24.5 7.5 Oct. - - -

Nov. 15.0 8.9 6.1 Dec. 11.0 1.0 10.1 1973 Jan. 11.0 2.2 7.8 Feb. 9.0 0.3 8.7 j Ma r. 18.0 8.0 10.0 Apr. 15.0 15.0 none x May 15.6 14.4 none x Jun.

~

25.4 22.2 3.2 Jul. 31.1 27.0 4.1 Aug. 31.0 23.0 8.0 Sep. 19.5 19.5 none x Oct. 22.0 17.0 5.0 Nov. 10.0 10.0 0  ?

Dec. - - -

1974 Jan. -

1.5 -

x Feb. 10.0 2.8 7.2 Mar. 14.4 10.0 4.4 Apr. 16.0 14.4 none x May - - -

x Jun. 30 23.3 '

22.2 none x l Jul. - - -

Aug. 32.0 26.6 5.4

~Sep. -18.5 15.0 3.5 Oct. 19.0 12.7 7.7 Nov. - - -

Dec. 11.0 4.4- 6.6 l

111.

l a

l

l

. I Table 35, cont.

Monthly Temperature, in 'C, 1971-1976 i Oyster Creek Bay Controls AT Plant off 1975 Jan. 10.5 4.4 7.1 Feb. 11.6 6.6 5.0 Mar. 7.5 5.0 2.5 x Apr. 21.0 20.0 none x May 28.0 23.0 5.0 Jun. - - -

Jul. 7 30.0 28.0 2.0 Aug. 30.0 23.0 7.0 Sep. 21.0 21.0 none x Oct. 17.0 13.0 4.0 Nov. 11.0 5.0 6.0 Dec. 2.0 3.0 none x 1976 Jan. 2.0 2.0 none x Feb. 10.0 9.0 none x Mar. 14.5 10.0 4.5 Apr. 23.0 14.0 9.0 May 25.5 19.0 6.5 Average AT (plant on): 6.4 I

l l

• From Oct. . 1971 to May, 1974, once-a-month sampling was done in the middle of the month. From June, 1974 onward unless a specific date is given, sampling-was done at the end of the month. A dash indicates missing data.

l

'112 l

Table 36 Monthly Salinities, in */.., 1971-1976 i

Oyster Creek

• Bay Controls" Creek Controls" i

1971 Oct. 20.5 15.8 -

Nov. 15.5 12.7 9.0 Dec. 21.5 19.0 16.0 1972 Jan. 13.0 6.0 6.6 Feb. 22.5 -

19.7 Mar. 23.5 17.0 9.5 Apr. 19.5 19.0 14.0 May 21.0 16.5 16.2 Jun. 22.5 12.5 -

Jul. - - -

Aug. 24.0 18.5 17.0 Sep. 25.0. 22.0 16.0 Oct. - - -

Nov. 11.7 12.0 3.5 Dec. - - -

1973 Jan. 20.0 2.5(ice) 2.0(ice)

Feb. 19.0 14.0 8.0 Mar. 23.0 20.2 -

Apr. 18.8 14.8 -

May- 18.5 20.8 14.4 Jun. 21.5 12.5 15.8 Jul. 19.2 10.0 8.1 Aug. 19.0 4.0 4.0 Sep. 22.0 14.0 14.0 Oct. 23.0. 20.0 18.0 1 Nov. 19.0 22.0 12.0 Dec. - - -

1974 Jan. 17.0 15.0 6.0 Feb. 22.0 20.0 10.0 Mar. 22.0 19.0 12.0 Apr. 18.5 16.0 13.0 May - - -

Jun. 30 14.0 14.0 10.0.

Jul. - - -

Aug. 21.0 17.0 14.0 Sep. 21.0 20.0 18.0 Oct. 22.0 17.0 19.0 Nov. - - -

Dec. 21.5 21.0 14.0 113 _

I J

q l

l

Table 36, continued Monthly Salinities, in */,,, 1971-1976 Oyster Creek Bay Controls Creek Controls 1975 Jan. 19.5 15-21 16.0 Feb. 21.5 15.0 17.0 Mar. 17.0 14-17 9.0 Apr. 17.0 15.0 4.0 May 19.0 16-19 9.0 Jun. - - -

Jul. 7 19.0 14-19 11.0 Aug. 19.0 16-21 7.0 Sep. 10.0 . 6.8-21.4 5.9 Oct. 19.0 16.8-21.6 12.2-16.6 Nov. 19.5 14.3-20.3 6.0-16.1 Dec. 7.0 7.1-23.0 8.9-17.2 1976 Jan. 17.0 15.8-19.7 1.9-2.8 Feb. 19.0 14.2-20.3 2.5-9.7 Mar. 21.6 14.5-22.9 6.6-14.5 Apr. 21.5 18.4-23.3 12.6-14.3 May 21.7 14.0-25.4 14.8

• Oyster Creek: average of 3 stations adjacent to number 10,11 and 12 in this report. Turners's stations were moved to the present location of stations 10, 11, and 12 when the marinas in Oyster Creek were demolished (May, 1975).

Bay Stations: station 1; 14 added in 1975.

Creek Station: Station 3; 7 added in late 1975.

114 l

l l i 1

-. . .-. -- . _ _ _ . .- ~ = _ . _ -- - .. .

I l

l

6.3 Early Shipworm Data, Barnegat Bay Although Turner was unable to quantify shipworm attack in the early years of her study, she did estimate numbers of the various species she found.

In addition, I have reviewed her x-rays. The raw data are available in the archives of the Department of Malacology, Academy of Natural Sciences. Table 37 summarizes the shipworm attack in cumulative panela during 1971-1976. The data are given as orders of magnitude. Comparison of the four station groups in Table 37 reveals a more clear-cut picture than emerged in later years. Not only the creek controls, but bay con-trols also contained only scattered shipworms, primarily Bankia gouldi.

Oyster Creek and the mouth of Forked River contained more species and more individuals than the other regions.

i Because it is difficult to separate distinguish Teredo furcifera and T.

bartschi f rom x-rays , question marks are included in Table 37 as regards l the Forked River area. From the x-rays, I suspect that some of the specimens assigned to T. furcifera by Turner might have been T. bartschi.

This is inconsequential; the major point is that both these tropical-subtropical species suddenly invaded Oyster Creek and were very abundant, ,

even occuring at Forked River Beach (station 8) and south of Oyster Creek (stations 14 and 15). Contrary to the statement in J.C.P. & L. (1978),

j "At its peak observed abundance, this species [T. furcifera] has occurred j in extremely low densities . . ." T. furcifera in 1974-1975 was abun-i dant and actively breeding. Reasons for its die-off in 1976-1978 are cited in the previous section (p. 110). These same reasons apply to the decline in numbers of the other species.  !

I The native Teredo navalis was common in 1971-1973, but died back at the end of 1973 and had an extremely poor settlement throughout Barnegat Bay '

in 1974. As in 1976-1982, many specimens died in late winter. Hillman et al. (1982) suggested that a haplosporidian parasite, perhaps intro-duced with T. bartschi or T. furcifera, was responsible for reducing the.

population of T. navalis. However, a decline was noticed in 1973, before the tropical-subtropical shipworms were established in the Barnegat Bay area (Table 37).

Turner's x-rays as well as Table 37 dramatically show the greatet ship-worm damage in Oyster Creek (her stations were in the immediate vicluity of our Stations 11 and 12, and at the mouth of Oyster Creek near our Station 10) and the mouth of Forked River, compared with control stations-both in the bay and in tidal creeks. Growth of shipworms was greater in l Oyster Creek. Even panels with fewer than 10 individuals of Bankia i gouldi were riddled after a few months ' submergence in Oyster Creek.

Turner's dramatic results were probably a function of the high 115

=-

Table 37 Shipworm Attack in Cumulative Panels, 1971-1976 In orders of magnitude

• Oyster Creek Creek Controls Bay Controls Submerged Month B.g. T.n. B.g. T.n. BA T.n.

Removed Sept. 16

'71 Oct. 0 0 0 0 0 0 Nov. 10* 0 0 0 0 0 Dec. 10* 10* 0 0 0 0 1972 Jan. 10* 10* 0 0 0 0 Feb. 10* 10* 0 0 0 0 i Mar. 0 10* 0 0 0 0 Apr. 0 10* 0 0 0 0 May 10* 10* 0 0 0 0 Jun. 0 10 0 0 0 0 Jul. 10* 0 0 0 0 0 Aug. 101 0 0 0 101 0 1 Aug. 18

'72 Sep. 101 10* 10* 0 10* 0 Oct. 101 10* 0 0 0 0 Nov. 101 10" 0 0 0 0 Dec. 101 10* O O 10* 0 1973 Jan. 101 101 0 0 0 0 l Feb. 101 101 0 0 0 0 Mar. 101 101 0 0 0 0 l Apr. 101 101 0 0 0 0 May 101 101 0 0 0 0 Jun. 101 101 0 0 0 0 l

l l

• 10* = 1-9; 101= 10-99; 102 = 100-999; 108 2 1,000 per panel.

A dash = missing data.  ? = species uncertain.

116

Table 37, cont.

Shipworm Attack in Cumulative Panels, 1971-1976 Dyster Creek Creek Controls Bay Controls Forked River Series Month B.g. T.n. T.f. T.b. B.g. T.n. B.g. T.n. B.g. T.n. T.f. T.b.

Sirheerged Removed

, Aug. 18 '72- Jul. 101 10* 0 0 10* O Aug. 101 0 101 0 101 0 '

Aug. '73 Sep. 10* 0 0 0 0 0 Oct. 10* O O O O O Nov. 10* 0 0 0 0 0

-Dec. - - - - - -

1974 U

" Jan. 10* 0 10* O 101 0 Feb. 10* 0 0 0 0 0 Mar. 10* 0 0 0 0 0 Apr. 10" 0 0 0 0 0 May - - - - - -

Jun. 101 goo 10* 10* -

0 0 Jul. - -

101 - - - -

Aug. 101 101 101 10* O O 10* O July '74 Sep. 101 0 102 10 2 10 0 101 0 0 0 101  ?

Oct. 101 0 101 103 0 0 101 0 0 0 102 7 Nov. 101 0 101 103 0 0 101 0 0 0 102 7 Dec. 101 0 102 102 10* O 101 0 0 0 10 2 7102 1975 Jan. 101 0 102 102 0 0 101 0 0 0 102 7102 Feb. 101 0 102 102 10* 0 101 0 0 0 102 fio2 Mar. 101: 0 101 101 10* 0 10* O O O 102 ?102 Apr. 101 0 101 10 1 0 0 10* O - - - -

May 101 0 102 102 goo 0 101 0 - - - -

. M

.O.

O I o m

oCO OOCC H -

o a G C l C OOO CCCO

> . m m .

.e4 9 h M

o C .

C 0

C.

O eC CCC CCCO-M "

W H \

o la4

. o o M.

C 0 C CCC CCCC t m m 1 CQ c

N

$ o o CCCC-(n .

OOO OOC

• 04 m H -m 4 m o u 8  %

m 4 .

o .

N C C CCO OOO OOOOh c%

m o e m O P d C

= > -

en m . w a w w e4 o

CQ M.

OOC mmm CCC OCCO C CQ M

m 4 0 rw c > 0

• O *e4 W OOO OOO OOOCO U M M C.

=

Q c-4 c H O

N c U M E a c X M CCC OOC OOOoC U U 0

• m 0 QQ

.O C W 4 c4 U H

M U . H w N o o o o N OOC COO OOV s.

U .O. m-m mm mm 9 H m 4

M  %

8 W . d M o o a W 0 W CCO CCO CCCC O k . mm mm

• 3 U H 6 h e4 k o o

.c 0 .

OOCCC en a CCC 000 mm u c. ~

. o o o M.

CCC CCC OOCC' M mm

'M N

"C' c . . . .. . . c . . . .

.c > M 00 & 4 > U N C .O k S4 h 4 0 C c0 uoW m aee4e CS h 4 t/3 0 2; A m M Ea4 E < E oo EM I e

N

'O =

G m M N N j uk = N G

w . _.

4 C &

Wc -e c (t) t/3 _M t/3 118 l

I

. -. __ .-_ _ _ _ _ _ _ . - - _ = _ _ = . _ _ - _ - _ - - - - - - _ - . .

f

, AT's especially in winter, and the large amount of untreated wood in ,

Oyster Creek and Forked River, harboring a huge shipwo rm population.

l I

Turner noted that the increase of Rankia gouldi in Stout's Creek during j late 1974 and early 1975 coincided with dredging activity there, which may have increased the salinity by causing a short-term increase in  ;

i mixing of water coming from Barnegat Bay. Table 36 does show more con-sistent high salinity f rom August, 1974 to February, 1975 compared with other years. These data emphasize the role of increased salinity in the shipworm outbreak in Oyster Creek and For'ked River.

There is one cautionary note in interpreting Table 37. Some eteulative panel series were submerged too late to catch the settlement of shipworms until the following sunune r . For example, the lack of shipworms after September, 1975, is due to a new series missing rnost of the settlement for that season.

Table 38 summarizes the settlement of shipworms on Turner's monthly

panels. Corresponding to Table 37, there was more settlement on panels in Oyster Creek than in the other areas. As in the years 1976-1982,

, Teredo navalls settled later in the year than Bankia gouldi; the intro-duced species that release pediveligers carried larvae nearly all year and had long settlement seasons. The settlement. In Oyster Creek and

Forked River of one or both introduced species in March-May, 1976, was j unusually early, compared with data for 1976-1982.

The breeding season of neither native species was earlier than normal in Oyster Creek, except perhaps in 1974. Even then, they did not settle before July, the month when Bankia gouldi normally begins to settle in Barnegat Bay. On the other hand, in two years prior to 1976, B. gouldi continued to settle in Oyster Creek into November. Any settlement of 2

this species ,beyond September is unusual, and most likely due to the j elevated temperature in Oyster Creek.

Besides Turner, several other workers have examined the shipworm problem l in Barnegat Bay. The first work, by Nelson (1922, 1923), described an outbreak of Teredo navalis along Barnegat Bay. No mention was made of an outbreak within Oyster Creek or Forked River. It is possible to corre-late Nelson's data with a drought in the early 1920's that increased the salinity of Barnegat Bay while decreasing the concentration of chemicals from the cedar swamps in bay waters. Either of these effects would cause-l greater survival and reproduction of T. navalis along the inner shore of l Barnegat Bay. In fact, these ef fects of drought are similar to those of the Oyster Creek Nuclear Generating Station in that it, too, caused an increase in salinity and decrease in swamp runoff proportional to the l

total amount of water flow, but in a more localized area.

119

Table 38 4

Colonization of Monthly Panels 1971-1976 Oyster Creek Holly Park Stout's Creek Forked River Year Month Removed 1971 Oct. Bg

Nov. Tn 1972 Jul. Bg Aug. Bg Bg

Sep. Tn; Bg Bg Oct. Tn, Bg Nov. Bg Dec.

1973 Jul. Bg Bg Aug. Bg Bg Bg Sep. Bg 1974 Jun. ?Tf Jul. Bg, Tf Aug. Bg, Tf, ?Tb Bg Bg Sep. Tf, Tb Tf, Tb I Oct. Tf, Tb Tf f Nov. Tf, Tb ?Tf Bay Controls Creek Controls 1975 Jul. 7 Bg, Tf, Tb Bg Bg, Tf, Tb Aug. Bg, Tf, Tb Bg Sep. Tb Bg Oct. Tb Nov. Tb Dec. Tb 1976 Mar. T. sp. (T . f_. ? )

Apr. T. sp.

May T. sp. T. sp.

l l

! 120 l

l

Test panels for shipworms were set out at the coast guard station near Barnegat Light on Long Beach Island from 1948-1967. Those studies showed heavy attack by Teredo navalis, similar to the findings of this report (William F. Clapp Laboratories, reported in Richards and Belmore, 1975).

Only since 1971 have there been shipworm studies in Oyster Creek and Forked River. This is not surprising. In the history of shipworm studies, one rarely finds data on a particular geographic area until a problem occurs. One can safely say that there was no report of an out-l break of shipworms in Oyster Creek or Forked River until 1971, despite I such findings for other parts of Barnegat Bay (sununarized by Richards and Belmore, 1975, p.5). A susunary report of Rutgers' 10-year study (Vouglitois, 1976) including pre- and post-operational data on the ben-thic flora and fauna of Barnegat Bay does not list teredinids as being present. The report was done to analyse potentially important changes in the marine biological environment due to power plant operations. Because teredinid surveys were not a part of these initial studies, one can assume there was no current or anticipated problem with shipworms in the late 1960's in the vicinity of Oyster Creek.

l Once an outbreak of teredinids was discovered in the areas adjacent to I

the Oyster Creek Nuclear Generating Station in 1971, studies were ini-tiated by J.C.P. & L. Wurtz (1971) conducted a study for J.C.P. & L. ,

followed by studies by Rutgers University (Shafto, 1974). Woodward-Clyde i

(1975) wrote a sununary of the physical behavior of the thermal plume, in addition to reports on woodborers, to J.C.P. & L. (Firth et al. ,1976).

Finally, there have been numerous quarterly and annual reports to J.C.P.

i & L. by Clapp Laboratories on a long-term shipworm study that ran con-currently with the one described in this report (Richards et al., 1976,

) 1978, 1979, 1980; Blake et al., 1981). One dif ficulty in analysing the 1 carly data is that J.C.P. & L. did change consultants so many times in 2

the course of investigating shipworm damage in Oyster Creek. Methods and stations changed, depending on the investigator, preventing the develop-

+

aent of a uniform data set until the work by the Clapp Laboratories began.

s Nevertheless, the overall pattern of data reported by all others is similar to that found by Turner and that described in this report. All researchers found an outbreak of shipworms in Oyster Creek, and all found the introduced species in about 1974. Richards et al. (1978) pointed out that Teredo bartschi was an indicator species, revealing areas influenced

} by the thermal plume. Their monitoring of Forked River began late and they were conservative in assigning small specimens to this species, but 4 eventually they too found T. bartschi in Forked River.

121

{

0 9

In summary, there is nothing in the data of other workers that would cause me to alter my findings described in the previous pages of this

, report, risagreements have occurred in the interpretation of the data, not in the data per se. T1e disagreements come in part because of sta-Listical methods used by others. For example, the Clapp laboratories compared Oyster Creek with outer bay stations of high salinity, rather than creek control stations as has been done in this report. I believe there is little basis for comparison between Oyster Creek and the outer bay, since we are talking about, on the one hand, a full-salinity ocean >

environment with constancy in physical parameters where one would expect many shipworms, and on the other hand, an estuarine environment with its inherent fluctuations in temperature, salinity, and currents. Even the proportions of the species involved in the attack are different. Teredo navalis is historically more common in the outer parts of Barnegat Bay, while Bankia gouldi is more common in the inner areas of the bay. I believe it is proper to focus on the alteration of Oyster Creek and Forked River and to compare these areas today with areas that reflect conditions in Oyster Creek and Forked River prior to 1969. In 1981, the Clapp Labs report was more in line with reports by Hoagland: "Thus it would appear that the impact of the OCNGS has been in allowing T.

bartschi to become established in Oyster Creek, and in aiding its spread to Forked River through recirculated effluent . . . its distribution in Barnegat Bay may be correlated with the operations of the OCNGS."

(Management summary, in Blake et al., 1981, p. ii-iii). However, I do disagree with several conclusions in that report, including the statement that Teredo navalis spawns in January in Barnegat Bay.

6.4 Other Relevant Shipworm Studies Shipworm outbreaks are usually studied on a case-by-case basis. However, a review of several key case studies does allow some generalizations to be drawn. The large outbreak in San Francisco in the 1920's, for exam-ple, shows the importance of drought in increasing salinity, similar to the situation in Barnegat Bay (Hill and Kofoid, 1927). Also well-con-firmed is the influence of a heated effluent in increasing population size and extending breeding periods of nuisance invertebrates (Gibbons, 1976; Pannell et al., 1962; Naylor, 1965 a and b). Specifically, thermal effluents have been implicated in wood-borer problems at Southampton and Swansea, England (Bell, 1949; Pannell et al., 1962).

The Millstone Point (Conn.) nuclear generating station is of more imme-diate relevance to the Oyster Creek study because Teredo bartschi was found there (Hillman et al., 1973; Battelle-Clapp Laboratories, 1978; Brown and Moore, 1977). The AT's and winter temperatures were generally 122 l

l

lower and there was far less untreated wood available in the Millstone .

effluent than in Oyster Creek. Probably for these reasons, T. bartschi has not caused major problems in Connecticut. That it was T. bartschi involved at both Millstone and Oyster Creek was confirmed by ele.tro-phoretic studies of the two introduced populations plus natural popu-lations in Florida (Hoagland, 1983; Hoagland and Turner, 1981).

6.5 A Model of Shipworm Outbreaks 6.5.1 Conditions for Shipworm Survival and Outbreaks The physical factors necessary and sufficient for growth and prolifer-ation of shipworms are: the presence of insufficiently treated or un-treated wood, aerobic waters uncontaminated with heavy metals, a salinity above a minimum species-specific level (about 10*/ in this study), and a temperature range compatible with the breeding and survival require-ments of the species (5-35" for Teredo bartschi) . While the other fac-tors operate on a threshold basis, temperature has more dramatic effect.

The greater the temperature, up to a point of stress, the greater the metabolism of the organism. If sufficient food (wood and plankton) is available, increased temperature results in greater growth, reproduction, and wood destruction. For most marine invertebrates, the optimal tem-perature is quite close to the maximum temperature for survival, and to the maximum temperature the animal is exposed to ir. its natural environ-ment. This was true for Teredo navalis and Bankia gouldi in Oyster Creek.

The diagram on the next page (Figure 8) represents an analysis of factors affecting shipworms in their environment. An outbreak occurs when new space becomes available to an organism in an ecosystem. Altering the relative strength of the arrows in Figure 8, or adding new components to the ecosystem, can be responsible. So can basic changes in physical parameters. For example, addition of wood or elimination of predators or competitors (Figure 8) can cause an outbreak. A drought that alters salinity can be responsible.

In Oyster Creek, a change in salinity made a large reservoir of untreated wood available. Simultaneously, there was an increase in organic matter in the water, from seepage of sewage into Oyster Creek and Forked River from septic tanks of houses that were increasing in number, especially in portions of Forked River, as well as from the mass of planktonic orga-nisms going through the cooling system of the generating station. Water flow increased, bringing a greater volume of water containing larvae of boring and fouling organisms and food for the adults past wooden struc-tures. The water was well-oxygenated. Finally, increase in temperature 123

Figure 8 Analysis of Factors Affecting Shipwcrms ir. their Environment O

Haplosporidian Flatworms Peresite 1

o l Adult Shipworms C 0 Limnorte Flatworm other Predatore Blvelves Shipworm Pedivellgers shipworm Veligers Ptsdators on Fouling Carnivorous "8 u Plankton ' *

(Ctenophores) o~

Plankton a

Planktoveres Fish Carnivores An arrow leads towards the organism that benefits from an interaction (usually a predator). A circle indicates an organism diminished by an interaction (usually predation or competition). A curved line from one organism back to itself represents negative feedback. The relationships involving species other than shipworms are generalized.

4'hysical factors that affect the diagram are: 1) Wood benefits shipworm pediveligers, Liamoria, and fouling invertebrates; 2) Increased current (to a point) benefits adult shipworms and fouling invertebrates; 3)

Increased silt impacts negatively on shipworms and fouling invertebrates;

4) Increased salinity up to full ocean salinity augments some parasitic microorganisms but diminishes others. It generally benefits the fouling invertebrate community and its predators, as well as wood-borers; 5)

Increased temperature augments growth and reproduction of all species up to the point of temperature tolerance of each species.

124 I

allowed for greater metabolic activity of boring and fouling organisms,-

and entry of additional species. It is clear that most of the changes associated with building and operating the Oyster Creek Nuclear Gene-rating Station worked to enhance shipworm populations.

The size of the population of Teredo bartschi in Oyster Creek is con-trolled by the number of surviving adults (related to temperatures during winter and severity of wood destruction), the date when the water reaches temperatures high enough to allow release of pediveligers in summer, and the water temperatures in summer that control the rate of growth and development of the shipworms. For example, the outage in 1980 caused very high mortality of T. bartschi by March, 1980. The delayed warmup of Oyster Creek postponed release of pediveligers. But finally, when they were released in September during a period of high water temperature, the population expanded rapidly.

6.5.2 Nursery Theory One hypothesis is that increased breeding of shipworms in Oyster Creek would cause a build-up of adult shipworms throughout Barnegat Bay. From the above section, it is clear that this could happen only if sufficient untreated or inadequately treated wood was available in Barnegat Bay.

Our investigations revealed that wood was available throughout the bay.

The data from 1971-1982 do not demonstrate a pattern of prolonged or early. breeding of native shipworms in Oyster Creek that go on to settle in Barnegat Bay. Plankton samples and monthly panels outside Oyster Creek and Forked River were negative for native shipworms except during periods when those stations were producing their own larvae. However, Oyster Creek did act as a nursery ground for T. bartschi and T. furci-fera. These introduced species spread to areas where conditions for their long-term survival were poor. Nevertheless, T. furcifera contri-buted to woodborer damage over a far wider extent of Barnegat Bay than covered by the thermal effluent. Teredo hartschi bred at the edges of the thermal effluent. The presence of the introduced species outside Oyster Creek demonstrated that larvae of the native species also must have lef t Oyster Creek for other parts of the bay. However, the extent to which this happened was probably small after 1974, when the introduced species began to dominate in Oyster Creek.

In order for the nursery theory to be realized, it appears that the AT in Oyster Creek would have to be at least 6-8 *C as it was in the early years of plant operations, to insure prolongation of the breeding season.

Food in the form of wood and plankton would have to be plentiful in Oyster Creek to support the higher. metabolism and greater reproduction of shipworms.

125

1 In summary, while Oyster Creek certainly contributed adult and larval shipworms to Barnegat Bay, no dramatic buildup of shipworms in the bay  !

occurred (except at stations also influenced by the thermal effluent such as those at the mouth of Forked River). Such a buildup is unlikely in the future, given the present AT's and the frequency of plant outages.

6.5.3 Niche Dimensions and Competition There is a distinct set of life histories, settlement periods, growth patterns, and physiological requirements for each of the teredi-nids in Oyster Creek. These differences are summarized in Figure 9 and Table 39. Most Bankia gouldi settle in June and July; most Teredo spp.

settle in August - early October. The different settlement periods allow for several species to coexist in Oyster Creek, despite competition for a

} limited resouce, namely wood. As new wood becomes available through the breeding season, we should expect proportions of species in the wood to change.

4 The offset in temperature requirements suggests mortality of the native species in summer, con.pensated by that of the introduced species in winter. It seemed that Teredo spp. were more susceptible to a microor-ganism than Bankia. Early settlement and rapid growth of Bankia, com-bined with lower mortality, would seem to give it a competitive advan-tage. Turner's data did show it increasing in abundance relative to T.

navalis.

However, during outbreaks after 1974, the introduced Teredo spp. domi-nated Oyster Creek and the mouth of Forked River. The reason must be cought in the life histories of the species. Bankia gouldi, with its spawning followed by planktonic larval development, produces widely-dispersed larvae with low survival. Teredo navalis, with its short-term brooded larvae, does only slightly better. But Teredo bartschi and T.

furcifera release pediveligers that can settle almost immediately, form-ing dense clusters. Data are not available for T. furcifera, but it is apparent that rapid maturation at a small size decreases the generation time for T. bartschi.

Therefore, the different life history strategies of Bankia gouldi and the introduced Teredo spp. allow for both to survive despite competition.

Teredo bartschi has the capacity to dominate. numerically and to recover quickly from a population crash, while B. gouldi is more widely-distri-I buted, longer-lived, and a more stable member of the boring and fouling communit.y. Electrophoretic studies (Hoagland, 1983) have also shown that B. gouldi is more variable than T. bartschi in its allozymes, but the lack of variability in the introducted T. bartschi has not seemed to affect its major ecological niche parameters.

126 l

l 1

FICURE 9 Ecological and Niche Differences between Teredinid Species A. Settlement of larvae. Percent of years in which larvae were found settling in a given month (data covering 1976-1982).

100-

• LEGEND:

A B. gouldt

$80- X T. bartechl 4 O T. navalis W

60-u.

O

$40-W O

C W 20-a v w, x

. . =

00 7 7 ."

. I I i i T T T JAN FEQ MAR APR MAY JUN JUL AUG SEP OCT NOV DEC MONTH B. Percent of years when mature larvae were present in a given month, in the brood pouch (deta covering 1976-1982).

100- W X M---X LEGEND:

u) x T. bartschi C80-4 , O T. navalis m

g 60- \g l O l -

Z 40-W O X (2

W20-0.

00 T T T - T I i i i i i i T JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC MONTH

.127

i ll ll I 8 l 5

f,3 lh c i s s ld lla t

r u v _

a oa b g n T BT .-

. 0

-l-I,3

~ ._9j .l ._ -

~

D: .

~~ . .

N .

E G

E L

i,2 5

. )

- C

('

e d' .

.~ . . _ . _ . -

l i .

hl ad .

cesl . .

i i u .

i,0 E nfd ong dd a en a

- 2R U

i z aei l b un rk ._

- T A

aat a _ .

R el aB r r .

ner . .

E d opo

_ I,5 P n

ad e

) s mf et d n

, E 1M saf u .

T eb oo .

n ,s b i .

l sne dii u d or ent t hiaa sd nr

. ..~.

I.o t aeie d rb p _

( temm oe l ct .

ay .

i al r t B ae n

et i n mw .

_ 1l l1 1 1 t atI t ,$

ogp peoe _ .

n h

yBas ret ar ._

t m i t - sr n1 ao i

l) r asass ef 0

se ii - - - . . - ~ . e nd xl 0 0 0 0 0 0 dieaa 5 0 nld - v 4 3 2 1 a aY a _

dh eiS e n dw yg.g_,g . , < E rl h o uo .Td t s e a( s r r e .e e e i yT pcdt _

mauid ept nn Tssia .

C 0

gM0

. Table 39 Major Ecological Differences and Similarities, Teredinidae in Barnegat Bay (Excluding Temperature and Salinity)

Differences T. bartschi T. navalis B. gouldi Maximum Adult Size 132 mm 360 mm 450 mm Size Smallest Brooding 9 4 mm 16 mm -

Minimum Generation Time <2 mo . 2-3 mo. >3 mo.

No. offspring per Brood ~103 +105 >105 Percent of Adults Brooding 35 <15 -

at one Time Larval Stage at Release Pediveliger Veliger Spawns Gametes Time in Plankton Few Days 2-3 Weeks > 1 month Potential Reprod. Season All year May-Oct. May-Sept.

(mature eggs present)

Settlement Period ?Apr.; June-Nov. June-Oct June-Sept.

Generations per Year 1-3 1-2 1 Sexuality ?Simult. hermaph. Protandrous Protandrous Relative Larval Mortality Low Moderate High Ave. First year Survival, .12 .54 .90 June-May (1976-1982)

Settlement pattern Clumped Random Random - uniform Lifespan in Nature 1-2 year 1-2 year >2 year Maximum Density per Panel ~2,000 ~500 ~100 (1976-1982)

Percent Polymorphic Loci 10-35 55 70 lieterozygosity (E) <.01 .07 .15 .13 Suscept. to MSX-Like Organism High High Low Similarities Preferred substrates (soft wood), position of settlement relative to currents and water column, food (as far as known), growth season (in Barnegat Bay).

129

6.5.4 Introduced Species: Generalizations Ecological differences between the teredinid species in Oyster Cre'eh are major (Figure 9; Table 39). The genetic and life history data reported in Table 39 were previously reported in Hoagland, 1983. Genetic infor-

. mation was obtained from electrophoretic studies of allozymes funded by the Fleischmann Foundation. The data show greater pclymorphism in spe-

, cies with longer planktonic dispersal.

i Teredo bartschi is genetically impoverished due to founder effects plus bottlenecks in New Jersey. However, monomorphism in the soluble proteins is not correlated with narrow physiological tolerances. There is a possibility that strong selective pressures, as evidenced by high adult mortality under low temperature stress, could drive the introduced popu-lations of T. bartschi to become better adapted to cold temperatures. In that case T. bartschi could spread more widely in the cold temperate region.

Although Teredo bartschi has built up very large populations in Oyster Creek almost to the exclusion of the native species, it has not become a major element in Barnegat Bay and has not replaced the native species.

It has the classical characteristics of a successful introduced, "oppor-tunistic" species (Turner, 1973). These are a high rate of increase (r),

high rate of survival of larvae, broad physiological tolerances, ability to hold brooding larvae over the winter, and hermaphroditism. Teredo bartschi is a good competitor in any one piece of wood because it has a shorter lifespan, reproduces at a smaller size, and hence can withstand

crowding better (has a higher carrying capacity) than the native species.

Its long reproductive season gives the potential for more reproductive l events per year than occur in the native species. However, it is unable i to dominate an entire area for any length of time, because its population

! structure is inherently patchy in time and space. Patchiness is caused by the lack of planktonic larval dispersal plus heavy winter mortality.

Even if T. bartschi evolved greater tolerance to low temperature, it j probably would not eliminate the native species because of the niche

differences associated with differences in life history. It does, how-ever, increase damage to wooden structures in those places where several species co-occur.

l 130 l

l

. - _ . .- ~. _ ____ _ . . ._. . -- --. _ _ .

l t

i a

6.6 The Boring and Fouling Community i

Use of an overlap value such as in Tables 29-32 to compare commu-q nities is useful to summarize large amounts of data. The difficulty in

interpretacion is that the taxa contributing to the overlap of two sta-i tion groups might be different from those contributing to the overlap of

! two others...the index tells us nothing of the actual species compo-

sition. The index also fails to express the variation inherent in the

! average percent cover values. Nonetheless, it does estimate community similarity.

It is interesting that Forked River differed in fouling compositon from Oyster Creek, and that Oyster Creek retained some elements charac-teristic of the creek fouling communities. These elements included j dominance of Balanus eburneus, green algae, and entoprocts.

Some fouling species were usually found in association, and others were rarely found together. Such nonrandom distributions may be due to ,

either biological interactions (e.g. , competition, predation) or environ-mental factors (e.g., salinity tolerance). For example, the nudibranch

Doridella obscura was always found feeding on a species of encrusting bryzoa, Membranipora sp., while caprellid amphipods were found on the I

algae Polysiphonia harveyi. The hydroid Gonothyra loveni harbored the polychaete Autolytus cortv2tus. The tunicate Perophora listeri was found only on the algae Champia parvula. On the other hand, the species of hydroids and algae at Stations 18 and 19 were rarely found at stations of the inner Barnegat Bay, probably due to physical environmental factors.

. Since the power plant began operating, the distribution of fouling organisms was altered at Oyster Creek's Stations 11 and 12 and Forked River's Stations 5 and 6 in the following ways: 1) there was a greater total number of species, compared with creek controls. This is because-the greater and more constant salinity allowed invasion of species from, Barnegat Bay, such as Microciona prolifera (the red sponge) and'many hydrozoans, algae, and polychaetes. Euryhaline estuarine species such as the barnacle Balanus eburneus, the sea anemone ' Hallplana luciae and the _ l flatworm Probursa veneris were, however, not eliminated from Oyster Creek

] and Forked River (Appendix C). 2) As documented in our quarterly reports j sad reports by Turner, there was more growth in winter of fouling orga-nisms, particularly Balanus eburneus, anemones, sponge, and Polysiphonia) but greater mortality in summer. 3) Settlement of a few invertebrates showed some differences between Oyster Creek and the other stations that might be due to temperature (Table 34).

f 131 i

s t

7m.,. . y -

There were no strong positive or negative correlations of teredinids with fouling organism distribution that could be associated with strictly biological processes such as competition, predation, or symbiosis (Table 33). No predator specific to teredinids was identified among the fouling community.

I conclude that salinity is the most important single factor deter-mining the species composition of the fouling community, with temperature secondary. Although the community is unstable everywhere in terms of species composition, the same growth forms (encrusting barnacles and bryozoa, solitary trunicates, filamentous bryozoa and/or hydroids, and filamentous algae, with associated polychaetes) recur over time. Sta-bility was lowest in Oyster Creek, due to late summer die-off at high tempe rature and to depostion of anoxic mud on test panels when Oyster Creek was dredged during our study.

In an earlier fouling study in Oyster Creek and Barnegat Bay, Shafto (1974) used some of the same stations as in this report. Her study was only of panels removed after 1 month or less, and only covered the period October, 1971 - September, 1972. As might be expected given the cir-cumscribed nature of the study, she found far fewer species than listed in this report. However, all of her 10 most dominant taxa were also common in my samples. Like me she found Hydroides dianthus to be common south of Oyster Creek, and Membranipora common in Oyster Creek. Other similarities with present study are the relatively great amount of Bowerbankia gracilis in Stout's Creek and Oyster Creek, and the scarcity of Botryllus schlosseri in Oyster Creek. Differences included the low number of Corophium Shafto found except at the Oyster Creek plant out-flow, and the low numbers of Mogula manhattensis and Polydora ligni she found in Oyster Creek. In general Shafto reported low diversity of fouling organisms in Oyster Creek, and similarity of the fouling commu-nities in Oyster Creek and Stout's Creek. She attributed these results to " stress" at these localities.

A few other studies have been done on invertebrates in Barnegat Bay.

Mountford (1980) found #nemiopsis leidyi in the water of Barnegat Bay; it can feed on teredinid larvae. Hein and Koppen (1979) did diatom studies, and found fewer species and lower diversity in the thermal effluent of Oyster Creek than at some other stations. Young and Frame (1979) found an extended breeding season of Balanus eburneus in Oyster Creek. Kennish and Olson (1975) found faster growth in winter but less growth in summer for bivalves (Mercenaria mercenaria) collected in the thermal effluent.

j Finally, Peterson (1979) found predation by starfish on mussels to be a

! major factor organizing the fouling community at Barnegat Inlet (our l Station 18). I emphasize how different the Barnegat Inlet area is from l

132 l

l l

l

the inner bay stations, where I never found mussels or starfish to be important in the fouling community.

On a raore theoretical level, Menon et al. (1977) reported on the relationship between seasonal hydrography, breeding periodicity, and recruitment in fouling communities. Menge and Sutherland (1976) also pointed out temporal heterogeneity as a major factor in fouling community structure. Dayton (1971) has focussed on the importance of both bio-logical and physcial disturbances in determining structure of epifaunal comununities . These papers show a theoretical basis for finding that physical distrubances repeated irregularly, such as unpredictible plant shutdowns causing sudden temperature change, dredging activity, or re-moval of substrates, would locally destabilize fouling communities.

Reducing variation in temperature or salinity might be expected to in-crease local stability. My findings are in harmony with those of Logan i and Maureer (1975) who emphasize that species diversity may go up in a I thermal effluent, due to the habitat being kept in a " pioneer" state, l with higher equitability of species. l 133

7. CONCLUSIONS The Oyster Creek Nuclear Generating Station was responsible for repeated shipworm outbreaks 'in Oyster Creek and Forked River, New Jersey, from 1971-1982. The outbreaks occurred primarny during periods when the plant remained operating and producing a thermal effluent during critical spring months. Increased salinity in Oyster Creek and the south branch of Forked River was a major factor that allowed shipworms to survive in these tidal creeks, compared with unaffected creeks such as Stout's Creek i and the middle branch of Forked River. A thermal effluent increased the grcwth rate of shipworms and allowed the survival of tropical-subtropical introduced species in Oyster Creek. The introduced species spread outside of Oyster Creek and : arvived and reproduced in Forked River when the

! plant was operating for long periods without a major outage.

An extc ided breeding season for shipworms was thought to be associated i with operation of the plant in early years (Turner, 1974). However, between 1976 and 1982, no one species clearly extended its reproductive season compared with control stations. Rather, Oyster Creek and Forked River contained more species than the control stations, and these species were slightly offset in their breeding seasons, making the combined breeding season of all species longer.

The currents in the vicinity of the Oyster Creek generating station allowed measurable recirculation of the thermal effluent into Forked River. This effect plus the pumping of large volumes of water up Forked River decreased winter ice cover in the lower portions of Forked River, and helped bring shipworm larvae into Forked River in summer. As pre-dicted by . engineering studies, a significant portion of the thermal effluent also went -south as far as _ the mouth of Waretown Creek, where the tropical-subtropical species were occasionally found.

The area affected by the thermal effluent included Oyster Creek from the I generating station to its mouth and Forked River from its mouth up the south fork to the generating station, as well as the stretch of coastline from Forked River to Waretown. In this area, heavy shipworm attack by four species, rather- than the native two, are attributed to operation of the generating station. A nursery effect whereby organisms bred in Oyster Creek and were broadcast elsewhere could be found only in Forked l River and Waretown.

The introduced species Teredo furcifera was already' dying out when .this study began.in 1976. T. bartschi, however, reached several peaks, corre-lated with power plant operation periods. The introduced species did not 135

i

> competitively replace native species of shipworms. The species differed enough in niche parameters (particularly temperature preference, dis-

- persal and settlement patterns, mortality. patterns and adult size) for ,

all to coexist, even in the same piece of wood. Therefore, the addition of a species in Barnegat Bay increased the total amount of damage due to woodborers.

i Teredo bartschi is small and very patchy in distribution, but can become very dense. Its generation time is shorter than that of the native species, and in general it has the ecological characters of an oppor-tunistic species. It seems to thrive despite very low genetic varia-bility For these reasons, T. bartschi can quickly recover from unfavor-able conditions when conditions do improve.

In 1971-1976, the AT in Oyster Creek was higher than from 1976-1981.

4 Dilution pumping was reduced or eliminated in winter, causing water temperatures in Oyster Creek to stay well above 5* C in some years. The resultant shipwona outbreak, compared with control stations, was dra-matic. In 1976-1982, removal of untreated, infected wood and reduction of the AT, especially in winter, were partially effective in reducing the shipworm outbreak, especially that due to the native species. However, the opportunistic life history characteristics of Teredo bartschi allowed i

it to build up huge populations in the the thermal effluent area whenever j favorable conditions returned.

l The fouling community in Oyster Creek and Forked River was made more.

complex and speciose with the increase in salinity and winter tempera-I ture. However, dredging activities, sudden temperature changes, and high summer temperatures caused instability in the fouling community in Oyster Creek. Such instability suggests that Oyster Creek would be a poor piace j for using a thermal effluent to cultivate shellfish.

For no apparent reason, the wood-boring gribble Liarioria tripunctata did not invade the area of the-thermal effluent, although it was found to the

south. There is evidence that Limnoria destroys young shipworms near the i surface of the wood. Our data also ' provide evidence that the tube worm Hydroides dianthus reduce shipworm infestation by preventing settlement of larvae. N. dianthus was rare in Oyster Creek but common at bay sta-I tions to the south.

l Oyster Creek contained more sponge, anemones, green and red . algae, and polychaete species than control creek r.tations. . Forked River also con- -

tained much sponge in addition to red algae and bryozoans. Additional analyses of the complex fouling community will continue beyond those mentioned in this report and will be the subject of future publications.

136 w w -- ,-- e w

8. PREDICTIONS and RECOMMENDATIONS Many predictions and recommendations have appeared in our quarterly reports. The major ones are repeated here, with a few additions. I proceed from general camments to ones specifically related to Oyster Creek.

1. Power plants built in estuaries threaten the structure of the estu-arine ecosystem if they involve changes in salinity as well as temperature. Therefore we should avoid building plants in estu-aries. If they are built, one can expect changes in the local marine flora and fauna.

2. There is a high likelihood of introduced species coming in and developing large populations in areas disturbed by a thermal eff-luent and those other physical changes associated with power plants.

3. Teredo species outbreaks can be expected in and near other temper-ate-zone marine power plant effluents if sufficient wood is present, if oxygen is not depleted in the water, and if no heavy chemical pollution is present.

4. The Oyster Creek situation showed that periodic winter-early spring shutdowns are effective in reducing shipworm populations, but only very prolonged shutdowns (longer than the no rn.a1 refueling cycle) can eliminate an introduced species population. Dredging can reduce populations of the shipworm (and fouling) species.

5. A reduction in AT can mitigate shipworm damage to some extent, but did not eliminate it in Oyster Creek.

6. As long as there is any unprotected wood in the area of Oyster Creek, Forked River, and adjacent areas cf Barnegat Bay, a breeding population of borers will be maintained under present operating conditions of the generating station. Short of eliminating the thermal effluent and elevated salinity entirely, the best course is for the generating station to assist riparian property owners to replace wooden structures with properly creosoted (at least 20 lb.

pressure) wood. In fact, this was partially done when shipworm easements were sold to some property owners along Oyster Creek.

However, such action has not been taken throughout the affected area. The goal is not only financial compensation but, from a biological prospective, elimination of infested wood. This removal j of untreated wood should extend to Forked River Branch and Forked '

River (mouth and S. Branch).

137 l 1

l l

i i

7. The time to clean up Oyster Creek and Forked River is in late spring ,

just prior +.o the breeding season, when populations of shipworms are l at their lowest.

8. If the Forked River plant is ever built, it should be built so as to minicially add to the AT or the salinity in either Oyster Creek or Forked River. If its outages were to coincide with those of the Oyster Creek plant, a potentially large and sudden environmental change could occur. If, on the other hand, the plants maintained different outage schedules, shipworm populations could be enhanced while potential for cultivating shellfish would also be enhanced.

138 i

I i

i i

REFERENCES Barlow, R.E. , D.J. Bartholomew, J.M. Bremner, and H.D. Brunk. 1972.

Statistical Inference under Order Restrictions. Wiley and Sons, London, 388 pp.

Battelle-William F. Clapp Laboratories. 1978. A monitoring program on the ecology of the marine environment of Millstone Point, Ct.

area. Annual Report for the year 1978. Presented to Northeast Utilities Service Company.

Bell, F.V.M. 1949. Timber structure, with particular reference to the maintenance of oil-loading jetties at Queen's Dock, Swansea.

Inst. Civ. Eng. (Marine and Waterways division), Sess. 1948-49:

3-11.

Blake, N.M., R.E. Hillman, P.I. Feder, and C. I. Belmore. 1981.

Study of woodborer populations in relation to the Oyster Creek Generating Station. Annual Report for the period December 1, 1979 to November 30, 1980, to Jersey Central Power and Light Co.,

Feb. 27, 1981. Report No. 15040. 15pp + Append. A-C.

Blum, H.F. 1922. On the effect of low salinity on T. navalis. Univ.

Calif. Pub. Zool. 22:349-368.

Bousfteld, E.L. 1973. Shallow-water gammaridean Amphipoda oE New England. Cornell University Press, Ithaca. 312 pp.

Brown, R.T. and P.F. Moore. 1977. An analysis of exposure panel data collected at Millstone Point, Ct. MIT, Cambridge, MA. Rep.

No. MIT-EL 77-015. 119 pp.

Culliney, J. 1975. Comparative larval development of the shipworms Bankia gouldi and Teredo navalis. Marine Biology 29:245-251.

Culliney, J.L., P.J. Boyle, and R.D. Turner. 1975. New approaches and techniques for studying bivalve larvae. In: Culture of Marine Invertebrate Animals, Smith and Chanley (eds.). Plenum Publishing Corporation, New York, pp. 257-271.

Dayton, P.K. 1971. Competition, disturbance, and community organ-ization: the provision and subsequent utilization of space in a rocky intertidal community. Ecol. Nonogr. 41:351-339.

Finney, D.J. 1982. Intervention and correlated sequen'.es of cbser-vations. Biometrics 38:255-267.

139-

Firth, R.W. Jr., et. al. 1976. Woodward-Clyde Consultants' Final report of 1974-1975 field and laboratory studies for Jersey Central Power and Light Co. Unpublished.

Fraser, C.M. 1944. Hydroids of the Atlantic coast of North America.

U. Toronto Press, Toronto. 451 pp., 94 pl.

Gibbons, J.W. 1976. Thermal alteration and the enhancement of spe-cies populations. In: Thermal Ecology II, G.W. Esch and R.W.

McFarlane (eds.). USERDA Symposium series (CONF-750425). pp.

27-31.

Gosner, K.L. 1971. Guide to Identification of Marine and Estuarine Invertebrates. Wiley-Interscience, New York, 693 pp.

Hein, M.K. and J.D. Koppen. 1979. Effects of thermally elevated discharges on the structure and composition of estuarine peri-phyton diatcm assemblages. Estuarine and Coastal Marine Science 9:385-401.

Hill, C.L. and C. A. Kofoid (eds.). 1927. Marine borers and their relation to marine construction on the Pacific Coast. Final Report, San Francisco Bay Marine Piling Committee (publ.), San Francisco. 357 pp.

Hill- n, R.E., N.W. Davis, and R.W. Cote. 1973. A monitoring program on the ecology of the marine environment of Millstone Point, Ct.

area, with special attention to key indicator organisms -- pre-operational phase. Summary Report to Northeast Utilities Service Company, Battelle-Columbus Laboratories, William F. Clapp Laboratories, Duxbury, MA.

Hillman, R.E., N.J. Maciolek, J.I. Lahey, and C.I. Belmore. 1932.

Effects of a Haplosporidian parasite, Haplosporidium sp. on species of the molluscan woodborer Teredo in Barnegat Bay, New Jersey. Journal of Invertebrate Pathology. 40 (3): 307-319.

Hoagland, K.E. 1983. Life history characteristics and physiological tolerances of Teredo bartschi, a shipworm introduced into two temperate zone nuclear power plant efflutats. Proceedings, Third Waste Heat Management and Utilization Conference. In Press.

Hoagland, K.E. and - L. Crocket. 1978. Analysis of Populations of Boring and Fouling Organisms in the vicinity of the Oyster Creek Nuclear Generating Station. Annual Progress Report, Sept. 1, 1977-Aug. 31, 1978. NTIS # NUREG/CR-0634. 113pp.

140

Hoagland, K.E. and L. Crocket. 1980. Ecological Studies of Wood-Boring Bivalves in the Vicinity of the Oyster Creek Nuclear Gene-rating Station, June 1 - Aug. 31, 1980. Report to the U.S. Nu-l clear Regulatory Commission. NTIS NUREG/CR-1855. 48 pp.

Hoagland, K.E., L. Crocket, and M. Rochester. 1978. Analysis of populations of boring and fouling organism in the vicinity of the Oyster Creek Nuclear Generating Station with discussion of rele-vant physical factors over the period: Dec. 1, 1977-Feb. 28, 1978, NTIS flNUREG/CR-0223. 44pp.

Hoagland, K.E. and R.D. Turner. 1980. Range extensions of teredinids

' (shipworms) and polychaetes in the vicinity of a temperate zone nuclear generating station. Marine Biology 58:55-64.

Hoagland, K.E., and R.D. Turner. 1981. Evolution and adaptive radia-tion of wood-boring bivalves (Pholadacea). Malacologia 21:111-148.

t Hoagland, K.E., R.D. Turner, and M. Rochester. 1977. Analysis of boring and fouling organisms in the vicinity of the Oyster Creek Nuclear Generating Station with discussion of relevant physical pa rameters over the period: April 30-Nov. 30, 1976. Report to the U.S. Nuclear Regulatory Commission. Jan. 1, 1977. 61 pp.

Jersey Central Power and Light Co. 1978. Oyster Creek and Forked River Nuclear Generating Stations 316 (a) and (b) Demonstration.

Vol. 1: Text; Vol. 2: Appendices Al-CI.

Kennish, M.J. and R.K. Olsson. 1975. Effects of thermal discharges on the microstructural growth of Mercenaria mercenaria. Environ-mental Geology 1:41-64.

Kofoid, C.A. 1921. Biological phase: the marine borers. In: Report-on the San Francisco Bay Marine Piling Survey. San Francisco, i San Frangisco Bay Marine Piling Committee of the American Wood-Preservers' Association; Revised ed. pp. 23-61, pls.

i Kofoid, C.A.,'and R.C. Miller. '923. Biological section. In: San Francisco Bay marina Diling Jurvey, 3rd Annual Progress Report.

pp. 40-53.

Kofoid, C.A. and R.C. Miller. 1927. Biological Section. In: Marine l

borers and their relation to marine construction on the Pacific l coast, C.L. Hill 'and C.A. Kofoid (eds.). San Francisco Bay Marine Piling Commission, S.F. pp.188-343.

141

-. .~ _

l l

l Logan, D.T. and D. Haurer. 1975. Diversity of marine invertebrates j in a thermal effluent. Journ. Water Pollution Control Fed.

i 47(3):515-523.

I 1

l McCain, J.C. 1968. The Caprellidae of the Western North Atlantic.

Bulletin U.S. National Museum. 278:147pp.

McQuire, A. J. 1971. Preservation of tish-r in the sea. In: Marine l borers, fungi, and fouling organisms of wood, Gareth Jones and Eltringham (eds.): Organization for Economic Co-operation and Development, Paris, pp. 339-346.

Menge, B.A. and J.P. Sutherland. 1976. Species diversity grad-ients: Synthesis of the roles of predation, competition, and temporal heterogeneity. Amer. Naturalist 10:351-369.

Menon, N.R., R.'J. Katti, and H.P.C. Shetty. 1977. Biology of Marine Fouling in Mangalore waters. Marine Biology 41:127-140.

Mountford, K. 1980. Occurrence and predation by Mnemiopsis leidyi in Barnegat Bay, New Jersey. Estuarine and Coastal Marine Science 10:393-402.

Nagabhushanam, R. 1960. A note on the inhibition of marine wood-l boring molluscs by heavy fouling accumulation. Science and Cul-ture 26:127-128.

Naylor, E. 1965a. Biological effects of a heated effluent in docks l at Swansea, South Wales. Proc. Zool. Soc. London 144:253-268.

Naylor, E. 1965b. Effects of heated effluents upon marine and estua-rine organisms. Adv. Marine Biology 3:63-103.

Nelson, T.C. 1922. The European pile worm: a dangerous marine borer l in Barnegat Bay, New Jersey. N.J. Agric. Exper. Station Circular 139:15 pp.

f Nelson, T.C. 1923. [ Report of the biologist.] Annual Report, New I Jersey State Agricult. Exper. Station, . 43 (for 1922):321-343,'4 pls.

Pannell, J.P.M., A.E. Johnson, and J.E.G. Raymont. -1962. An investi-gation into the effects of warmed waters from Marchwood power l station into Southampton water. Proc. Inst. Civil Engineoring l

23:35-62.

142 l

t I

Peterson, C.H. 1979. The importance of predation and competition in organizing the intertidal epifaunal communities of Barnegat Inlet, New Jersey. 0ecologia 39:1-24.

Pilsbry, H.A. 1916. The sessile barnacles (Ciripedia) contained in the collections of the U.S. National Museum; including a mono-graph of the American species. U.S.N.M. Bulletin 93:366 pp, 76 pls.

! Pringsheim, E.G. 1964. Pure Cultures of algae, their preparation and maintenance. Hafner Co., N.Y. 119 pp.

Richards, B.R. and C.I. Belmore. 1975. Final report on evaluation of the extent and effect of the marine woodborer population in Oyster Creek upon the overall Barnegat Bay marine woodborer popu-lations. Report to Jersey Central Power and Light Company, Oct.

15, 1975. Report #14609. Battelle Columbus Laboratories, 39 pp.

Richards, B.R., C.I. Belmore, and R.E. Hillman. 1979. Progress report for the 17th quarter on woodborer Study associated with the Oyster Creek Generating Station to Jersey Central Power and Light company, May 5, 1979 to August 8, 1979. Report No. 1493, September 15, 1979. Battelle Columbus Laboratories, Clapp Laboratories, Duxbury, Mass., 22 pp.

Richards, B.R., C.I. Belmore, R.E. Hillman, and N.J. Maciolek. 1980.

Annual Report for the period Dec. 1, 1978 to Nov. 30, 1979 on Woodborer Study associated with the Oyster Creek Generating Station to Jersey Central Power and Light Company. Feb. 29, 1980. Report #14968. Battelle Columbus Laboratories, William F.

Clapp Laboratories, Duxbury, Mass., 18pp. + Append. A-C.

Richards, B.R., A.E. Rehm, C.I. Belmore, and R.E. Hillman. 1976.

Woodborer Study associated with the Oyster Creek Generating Station. Annual Report, June 1, 1975-May 31, 1976. Report

1. 14729 to Jersey Central Power and Light Company.

Richards, B.R., A.E. Rehm, C.I. Belmore, and R.E. Hillman. 1978.

Annual Report for the Period June 1, 1976 to November 30, 1977 on Woodborer Study Associated with the Oyster Creek Generating Station, to Jersey Central Power and Light Co., Feb. 1, 1978.

Scolinick, 1975. Federal permit to discharge In: J.C.P. and L.

Co., 1978. Oyster Creek and Forked River Nuclear Generating Sta-tion 316(a) and (b) Demonstration. Vol. 1.

143

d.

Shafto, S.S. 1974. The boring and fouling community of Barnegat Bay, New Jersey. Master Thesis, Rutgers University, New Brunswick, N.J.

Smith, R.I. 1964. Keys to Marine Invertebrates of the Woods Hole Region. Marine Biological Laboratory, Woods Hole, Mass. 208 pp.

Sokal, R.R., and F.J. Rohlf. 1969. Biometry. San Francisco, Freeman, 776 pp.

Sutherland, J.P. 1974. Multiple Stable points in natural commu-

! nities. Amer. Naturalist 108:859-879.

Taylor, W.R. 1969. Marine Algae of the North Eastern Coast of M.

America. The University of Michigan Press, Ann Arbor. 509 pp.

Turner, R.D. 1966. A Survey and Illustrated Catalogue of the Tere-dinidae. Museum of Comparative Zoology, Cambridge, Mass., 265 PP-Turner, R.D. 1971-1976. Reports on panels removed from Oyster Creek and Adjacent Stations. Monthly unpublished reports available from the archives, Acad. Nat. Sciences Dept. of Malacology.

Turner, R.D. 1973. Wood-boring bivalves, opportunistic species in the deep sea. Science 180: 1377-1379.

Turner, R.D. 1974 a. In the path of a warm, saline effluent. Ameri-can Malacol. Union Bull. for 1973, 39:36-41.

i Turner, R.D. 1974 b. The introduction of Teredo furcifera von Martens into Oyster Creek, Waretown, New Jersey. Report to marina owners and AEC. 4 pp: 3 pls.

Turner, R.D. Sept. 1974 c. Report on panels removed Aug. 27, 1974, from Oyster Creek, Stout's Creek and Holly Park. Report ' to marina owners and AEC. 16pp, 11 pls.

Turner, R.D. 1975. Report on _ panels removed from Oyster Creek, Forked River Beach, Stout's Creek, and Holly Park on January 26, 1975. Report to marina owners and AEC: 12pp, 6 pls.

Turner, R.D., and A.C. Johnson. 1969. Some Problems and Techniques l in Rearing Bivalve Larvae. Bull. American Malacological Union l for 1969: 9-13.

l l 144-l I

U.S. Atomic Energy Commission, Directorate of Licensing. 1973.

Draft environmental statement related to the Oyster Creek Nuclear Generating Station, Jersey Central Power and Light Company.

Docket No. 50-219, Chapter 5, p. 17, paragraph 5.5.21. July, 1973.

U.S. Atomic Energy Commission, Directorate of Licensing. 1974. Final environmental statement related to the operation of Oyster Creek Nuclear Generating Station, Jersey Central Power and Light Com-pany. Dec., 1974. Docket No. 50-219.

Vougli.tois, J. 1976. The benthic flora and fauna of Barnegat Bay

'efore o and after the onset cf thermal addition ---

a suauna ry analysis of a ten year study by Rutgers University. Unpublished report, Jersey Central Pcwer and Light Company.

Woodward-Clyde. 1975. The physical behavior of the therma. plume discharged from the Oyster Creek Nuclear Generating Station.

Final Report, July 31, 1975. (Reprinted in JCP&L, 316 Demonstra-tion, Vol. 2, appendix B-3.)

Wurtz, C.B. 1971. Shipworms at Oyster Creek, N.J. An investigation made for Jersey Central Power and Light. Dec. 13, 1971.

Young, J.S. and A.B. Frame. 1976. Some effects of a power plant effluent on estuarine epibenthic organisms. Int. Revue ges.

Hydrobiol. 61(1):37-61.

1 145

APPENDIX A: STATION LOCALITIES STATION NUMBER NAME DESCRIPTION COORDINATES 1 Holly Park Dick's Landing Lat. 39 54' N Island Drive Lon. 74* 8' W Bayville, N.J.

Bay control 2 Mouth of Last Lagoon toward mouth 39 52' N Cedar Creek South Side 74* 8.5' W Estuarine control 3 Stout's Creek End of Raleigh Drive 39* 50.7' N Gustav Walters' residence 74 9.8' W Estuarine control 4 Mouth of South Shore 39* 49.6' N Forked River Developed property 74* 9.8' W Possible temperature increase, increased oceanic influence due to reverse flow 5 Leilani Drive At branch point of 9* 49.6' N Forked River ,4 10.5' W 6 Elk's Club South Branch 39 49.4' N Forked River 74* 10.9' W Increase in salinity due to plant intake canal 7 Grant's Boats Middle Branch, Forked River- 39 49.6' N just S. of State Marina 74* 11.6' W 8 Bayside Beach On bay between Oyster Creek 396 49.0' N Club and Forked River across 74* 9.7' W from 1815 Beach Blvd.,

Forked River, N.J.

femperature increase since plant operation.

147

i I

STATION NUMBER NAME DESCRIPTION COORDINATES 9 Intake Canal House closest to intake canal 39 49.2' N Salinity effect; strong 74* 12.2' W current upstream 10 Kochman's End of Compass Rd. on 39* 48.5' N Residence #1 Lagoon, Oyster Creek 74* 10.6' W Waretown, N.J.

Temp'rature, salinity.

siltation increase 11 Crisman's Dock Ave. on Oyster Creek, 39 48.5' N Residence Waretown, N.J. 74* 11.0' W Temperature, salinity, siltation increase 12 Gilmore's 20 Dock Ave. on Oyster Creek 39 48.5' N Residence Waretown, N.J. Temperature, 74 11.3' W salinity, siltation increase 13 Rte 9 Bridge Oyster Creek just'below 39 48.7' N discharge canal. Temperature, 74 12' W salinity, siltation increase 14 Cottrell's End of North Harbor Rd. 39* 47.7' N Clam Factory Waretown, N.J. (Mouth of 74* 10.9' W Waretown Creek). Within but near limits of reported thermal plume

• 15 Carl's Boats Washington & Liberty Sts. 39* 47' N Waretown, N.J. (Bay control) 74* 11' W 16 Iggie's Marina East Bay Ave, Barnegat, N.J. 39* 45' N Same purpose as Loc.15 74* 11.5' W 17 Manahawkin Bay At bridge to Long Beach Is. 39* 40' N Same purpose as Loc. 15 74* 13' 14 148

b STATION NUMBER NAME DESCRIPTION COORDINATES 18 Barpegat Light Marina adjacent to Coast 39* 45.8' N Guard Station 74* 6.5' W 19 Long Beach Bayview Marina 39* 17.4' N Island 74 54' W 20 Cedar Creek Opposite home of 39* 52.1' N Mr. and Mrs. Sokol.ich 74* 9.5' W 415 Terry Ave. (Not on map)

Inland from Station 2, At point where stream narrows.

• In May, 1982, Sta. 14 was moved to 19 Jolly Roger Way, Waretown, NJ, across Waretown Creek from the old site.

i i

~

t l

r I

149

APPENDIX B DATA COLLECTED SEPT. - NOV., 1982 The following tables summarize data collected from September to November, 1982. These are the last months of field work on this project. The AT during this period (Table A1) was about 4 C, close to the average for the entire proj ect (1976-1982). Salinities were the same or higher in Forked River than in Oyster Creek, and Oyster Creek had about the same salinity as the stations on Barnegat Bay (Table A2). Again, this is the same pattern as described for all the years 1976-1982.

There were very few living or dead shipworms in cumulative panels (Tables A3, A4). No Teredo bartschi were found. Over all stations, T. navalis was twice as abundant as Bankia gouldi, except in the November panels.

Only at station 18, Long Beach Island, was there a heavy settlement of T.

navalis. In Oyster Creek, B. gouldi and T. navalis were in equal num-bers. Outside of Long Beach Island, the heaviest infestation was in Forked River, followed by Holly Park.

Mortality occurred primarily in Forked River specimens of Teredo navalis (Table A5). Only one Bankia gouldi was found deaa. The mortality re-ported in fall cumulative panels is of young specimens, as can be seen by the sizes of the dead specimens (Table A6). The largest specimen of each species was in Oyster Creek in November, but at other stations in September and October.

The yearly panel series was concluded in September (Table A7). As in the cumulative panels, there were no living Teredo bartschi. However, there were numerous dead specimens in Oyster Creek. Overall mortality was thus very high in Oyster Creek but very low at the other stations (last column, Table A7). The large size of some shipworms from the September yearly panels (Table A8), compared with Table A6, indicates that at least a few of the specimens were from the 1981 year-class.

The panels submerged in August and removed in September, 1982, contained very few shipworms. There was one borehole in the panel from station 1 (Holly Park), and one 8-mm long living Bankia gouldi in the panel from station 8 (Bayside Beach Club). Settlement was absent from Oyster Creek during the fall, 1982 period.

Several specimens of adult Teredo navalis taken frcm cumulative and yearly panels were carrying larvae (Table A9). Oyster Creek had propor-tionally no more brooding individuals than other stations. Many of the largest specimens were not carrying larvae.

150 a

.i 1

Table A10 reviews newly-settled fouling organisms, listed in rank abun-dance under each station number. The data were taken from the November monthly panels. The creek control, station 3, was relatively impover-l ished in fouling species compared to the other stations. At Waretown,

' Botryllus schlosseri settled heavily and may have excluded other species.

i Other stations were rather similar, especially Oyster Creek and Forked River. These stations had the greatest number of fouling species, ex-cluding species that could crawl onto the racks rather than settling anew.

i f.

I

(

l 4

l

)

1 4

l l

151 l

l l

~

. _ . . ._4.., , . _ _ . . ._ __ _ .

Table A1 Temperature Profiles in C, September - November, 1982 Station Sept. 8, 1982 Oct. 8, 1982 Nov. 8, 1982 Differential among months D

1 21.0 20.5 12.0 9.0 3 21.0 23.0 14.0 9.0 b b 4 20.5 21.0 12.0 9.0 b

5 20.5 21.0 13.0 8.0 8 23.0 23.0 13.0 10.0

' 8 10 24.5" 24.0 15.0 9.5 8

h 11 24.0 24.5 15.0" 9.5 8

12 24.0 24.5 15.0* 9.5 D D 14 21.5 20.0 12.0 9.5 Differential 4.0 4.5. 3.0 among stations

" highest value each-month b

lowest.value each month Note: Accuracy to 0.5 *C

Table A2 Salinity Profiles in */.., September - November, 1982 Differential Station Sept. 8 Oct. 8 Nov. 8 among months 8

1 25 22 28 6 b b b 3 18 37 22 5 8

4 25 27 26 2 5 25 27" 26 2 8

8 25 26 28 3 10 25 25 28* 3 11 25 24 26 2 12 24 24 26 2 a

14 26 24 24 2 Differential 8 10 6-among stations

" highest value each month lowest value each month Note: Accuracy to i1*/oo 153

Table A3 Numbers of Living Shipworms in Cumulative Panels Submerged May_9, 1982 Date Removed: Sept. 8, 1982 Oct. 8, 1982 Nov. 8, 1982 Station B.g. T.n. Total BA T.n. Total B.g. T.n. Total 1 6 4 10 8 2 10 9 0 9 3 0 0 0 0 0 0 0 0 0 4 1 10 11 2 9 11 0 1 1 5 1 6- 7 1 5 6 0 2 2 8 1 4 5 1 3 4 1 2 3 10 0 0 0 0 0 0 2 0 2 11 0 0 0 1 0 1 2 0 2 12 0 0 0 0 0 0 0 1 1 14 0 0 0 0 0 0 1 0 1 g T5* - - -

0 >100 >100 - - -

s.n -

Totals 9 24 33 13 19 32 15 6 21 1 2 1 3 2 2 4 0 2 2 3 0 0 0 0 0 0 0 0 0 4 0 2 2 0 1 1 0 0 0 5 3 9 12 3 6 9 2 9 11 8 3 3 6 1 1 2 2 4 6 10 0 0 0 0 0 0 0 0 0 11 0 1 1 0 2 2 0 0 0 12 0 1 1 0 0 0 0 0 0 14 0 0 0 0 0 0 0 0 0 T5* - - -

0 >100 >100 - - -

11* ' - - -

2 0 2 - - -

Totals 8 17 25 6 12 18 4 15 19

• Not included in-totals. Animals used for histology. Sta. 18 is estimated.

Table A4 Numbers of Living Shipworms plus Empty Tubes Cumulative Panels Submerged May 9, 1982 Date. Removed: Sept. 8, 1982 Oct. 8, 1982 Nov. 8, 1982 Station .BA T.n. Total Bg T.n. T.sp. Total Bg T.n. T.sp. Total 1 6 4 10 8 2 0 10 10 0 0 10 3 0 0 0 0 0 0 0 0 0 0 0 4 1 12 13 2 12 0 14 0 6 0 6 5 1 7 8 1 8 1 10 0 3 1 4

'8 1 4 'S 1 3 0 4 1 3 0 4 10 .0 0 0 0 0 0 0 2 0 0 2 11 0 0 0 1 0 0 1 2 1 1 4 12 0 0 0 0 0 0 0 0 1 0 1 l 14 0 0 0 0* 1 0 1 1 0 0 1

-18# ' - - -

0 >100 0 >100 - - - -

u-

" " 26 40 16 14 2 32 Totals 9 27 36 13 1 1 2 1 3 2 2 0 4 0' 2 0 2 3 0 0 0 0 0 0 0 0 0 0 0 4 0 2 2 0 3 0 3 0 1 0 1

-5 3 9 12 3 8 0 11. 2 9 0 11 8 3 3 6 1 2 0 3 2 6 0 8 10 - 0 0 0' O O O O O O O O 11- 0 1 1 0 2 0 2 0 0 0 0 12 0 1 1 0 0 0 0 0 0 0 0 14 0 0 0 0* 0 0 0 0 0 0 0

>100 0 >100 18# - - -

0 - - - -

j 11# extra - - -

2 0 0- 2 - - - -

Totals 8 17- 25- 6 17 0 23 4 18 0 22

• 1 borehole in each of the starred panels.

. #Not included in. totals.

Table AS Percentage of Specimens that were Alive when Collected, Cumulative Panels Date Removed: Sept. 8, 1982 Oct. 8, 1982 Nov. 8, 1982

-Number Total no. Number Total No. Number Total No.

Living Tubes  % Living Tubes  % Living Tubes  %

Station Specimens Observed Alive Specimens Observed Alive Specimens Observed Alive 1 10 10 100 -10 10 100 9 10 90 3 0 0 -

0 0 -

0 0 -

4 11 13 85 11 14 79 1 6 17 5 7 8 88 6 10 60 2 4 50 8 5 5 100 4 4 100 3 4 75

10. 0 0 -

0 0 -

. 2 2 100 11 0 0 -

1 1 100 2 4 50 g 12 10 0 -

0 0 -

1 1 100 y M- 0 0 -

0 1 0 1 1 100

-18 - - -

>100 >100 * - - -

Totals 33 36 92 32 40 80 21 32 66 1 3 3 100 4 4 100 2 2 100 3 0 0 -

0 0 -

0 0 -

4 2 2 100 1 3 33. 0 1 0

5. 12 12 100 9 11 82 11 11 100

=8 6 6 100 2 3 67 6 8 75 10 0 0 -

0 0 -

0 0 -

11 1 1 100 2 2 100 0 0 -

12 1 I 100 0 0 -

0 0 -

M 0 0 -

0 0 -

18 - - -

>100 >100 - - -

11 extra - -

.- 2 2 100 - - -

Totals 25 25 100 18 23 78 19 22 86

• Not calculated. Numbers are. estimates-only.

l

Table A6 Length Ranges of Shipworms, in mm, Cumulative Panels Submerged May 9, 1982 Date Removed: Sept. 8, 1982 Oct. 8, 1982 Nov. 8, 1982 Station BA T.n. BA T.n. BA T.n.

1 32-75* 53-103 73-169 138-215 33-155 3

8 8 8 4 71 14 -83 8 26-121 34 -154 328-115 5 42 16-42 189 14*-137 81 -156 8 45 43-90 194 91-155 101 67*-212 10 177-274 ,

11 215 194-323* 99" 12 220*

8 14 28 112 18 7-241 Replicates 1 56-64 120* 148-260* 120-230 203-211 3

8 4 11-20 31*-88 8

4 5 9-68 19-85 17 -140 150-230 61-212 8

8 5-19 31-81 195 136-148 122-146 49 -219 10 11 109 162-164 11 extra 103-160 12 37 14 18 10-250*

• Largest specimen each species, each month. -

Dead i

157

Table A7 Number of Shipworms in Yearly Panels Removed September. 8,1982 Living Living plus Dead Teredinid Total Total Percent

. Station B.g. T.n. B.g. T.n. T.b. Boreholes sp. Livi Living & Dead Survival 1 3 1 3 1 0 0 0 4- 4 100 3 0 0 0 0 0 0 0 0 0 -

< 4. 0 4 0 4 0 0 0 4 4 100 d'

5- 1 2 1. 2 0 0 0 3 3 100 8' O 1 0 1 0 0 0 0 1 100 10 0 0 0 0 0 1 0 0 1 0 11 0 1 0 1 0 14 1 1 16 6 12 0 0 0 0 105 0 0 0 105 0 Totals 4= '9 4 9 105 15 1 13 134 10 1 Replicate 0 .0 0 0 0 0 0 0 0 -

5 Replicate 1 6- -1 6 0 0 0 7 7 100 11 Replicate' O O O O .0- 5 0 0 5 0 1 6' 1 6 0 5 0 7 12 58

i i- Table A8

, . Length Ranges of Shipworms, in mm, i Yearly Panels Removed Sept. 8, 1982

Station B.g. T.n.

1 33-69 119-3 - -

! 4 -

31-57

! 5 20 11-22 5 repl. 165* 80-165*a 8 -

11 10 _ _

11 -

5-49 j 12 -- -

i

• Largest specimen, -ach species

" Removed one month later i

5 i

i 9

i J

t l

4 l

i 159

._._..: . i-. - - _ , .. _ . . . -. _ _ . - - - _ _ . . _ . - - .--_ _,

. _ _ _ - _ _ - _ _ - _ _ _ _ _ _ _ . .- _ - _. - -. . = .._ .

Table A9 Percentage of Living Teredo navalis Carrying Larvae in the Gills Max. Length Min. Length Max. Length Min. Length  % of Adult Month Months of Ship- of Ship- of Ship- of Ship- Shipworms Panel Sta. Removed Submerged worms with worms with worms without worms without with Compo-La rvae(mm) Larvae (mm) Larvae (mm) Larvae (mm) Larvae sition IC* Sept. 4 103 103 78 53 25 4 adults, 4 total living 4C Sep t'. 4 83 83 65 14 10 10 adults, 10 total living SC Sept. 4 - -

35 16 0 6 adults, 6 total living 8C Sept. 4 90 90 70 43 25 4 adults, 4 total living h IE* Sept. 4 - -

120 120 0 1 adult, I total living 4E Sept. 4 - -

20 11 0 1 adult, 2 total living 5E Sept. 4 - -

85 19 0 9 adults, 9 total living 8E' Sept. 4 81 54 31 31 67 3 adults, 3 total living 11E Sept. 4 109 109 - -

100 1 adult, I total living 12E . Sept. 4 - -

37 37 0 1 adult, I total ,

living

• C = cumulative panel; E = replicate of cumulative panel

r Table A9 cont.

Percentage of Living Teredo navalis Carrying Larvae in the Gills Max. Length Min. Length Max. Length Min. Length  % of Adult Month Months of Ship- of Ship- of Ship- of Ship- Shipworms Panel Sta. Removed Submerged worms with worms with worms without worms without with Compo-Larvae (mm) Larvae (mm) Larvae (mm) Larvae (mm) Larvae sition 1Y Sept. 12 - -

119 119 0 1 adult, I total living 4Y Sept. 12' - -

57 31 0 4 adults, 4 total.

living 5Y Sept. 12 - -

22 11 0 1 adult,

. 2 total living 8Y Sept. 12 - .- 11 11 0 0 adults,

. g 1 total p living 11Y Sept. 12 - -

49 49 0 1 adult, ,

I total '

living; IC Oct. 5 - -

215 138 0 2 adults, 2 total living 4C Oct. 5 127 127 154 34 11 9 adults, 9 total living SC' Oct. 5 - -

137 50 0 5 adults, 5 total living 8C Oct. 5 - -

155 91 0 3 adults, 3 total living 4

IE 'Oct. 5 - -

140 17 0 2 adults, 2 total living

.-- . _ _ _ _ _ - _ _ - _ _ _ _ _ - - . .. . - . -- - _ .- _- _-. _ _ ~

Table A9 cont.

Percentage of Living Teredo navalis Carrying Larvae in the Gills Max. . Length Min. Length Max. Length Min. Length  % of Adult Month Months of Ship- of Ship- of Ship- of Ship- Shipworms Panel Sta. Removed ~ Submerged worms with worms'with worms without worms without with Compo-Larvae (mm) Larvae (mm) Larvae (mm) Larvae (mm) Larvae sition ,

4E Oct. 5 - -

88 88 0 1 adult, 1 total living 8E Oct. 5 - -

148 148 0 1 adult, I total living 11E Oct. 5 164 162 - -

100 2 adults, ,

2 total living 4C Nov. 6 104 104 - -

100 1 adult, I total 5

living SC. Nov. 6 156 114 - -

100 2 adults, 2 total living 8C Nov. 6 212 212 '70 70 50 2 adults, 2 total living 12C Nov. 6 220 220 - -

100 1 adult, I total living IE Nov. 6. - -

211 203 0 2 adults, 2 total living SE Nov. 6 212 166 191 61 56 9 adults, 9 total living 8E Nov. 6 219 119 154 130 50 4 adults, 4 total living

a Table A10 New Settlement of Fouling Organisms October 8 - November 8, 1982 Station 1 3 i 1 Electra crustulenta Barnacles Polysiphenia sp. Botmilus schlosseri Anemone Barnacles Electra crustulenta Nereis succinea* Electra crustulenta Barnacles Amphipods ' Batm11us schlosseri Polysiphonia sp.

Nereis succinea*

Amphipods"

• Botmilus schlosseri Barnac1 Molgula a nhattensis Barnacles Electra crustulenta Molgula manhattensis Electra crustulenta Molgula manhattensis Barnacles Electra crustulenta Barnacles Electra crustulenta Nereis succnea" Hydroides dianthus lh Botmllus schlosseri

" Unattached' organisms; capable of crawling from older panels.

4 APPENDIX C LIST OF SPECIES FOUND IN BARNEGAT BAY l Taxon Stations Where Found* l

! Cyanophyta all oscillatoria sp.

Spirulina subsalsa Microcoleus lyngbyaceus Chlorophyta Monostroma oxyspermum Enteromorpha intestinalis 4, 5, 6, 8, 11, 12,.14, 15 E. prolifera 3, 15, 17, 18, 19 Ulva lactuca 1, 2, 3, 4, 5, 6, 8, 9, 10, 11, 12, 13 14, 15, 16, 17, 18, 19

! Cladophora expansa 2, 4, 5, 6, 10, 11, 12, 14, 15, 16, 17, 18, 19 Cladophora gracilis 18, 19 Codium fragile 4, 10, 11, 15, 19 i

Xanthophycophyta

Vaucheria sp.

Ectocarpus conferroides 4, 6 E. siliculosus 4 i E. tomentosus 4 Pylaiella littoralis 4, 6, 14, 19 Punctavia sp.

Rhodophyta

, Rhodochorton rothii j Agardhiella tenera 4, 5, 6, 8 Neoagardhiella baileyi 4, 5, 10 Gracilaria foliifera 16 Champia parvula 1, 2, 4, 5, 8, 9, 10, 11, 12, 14,-

15, 16, 17, 18, 19 Rhodymenia palmata 19 Antithamnion sp. (cruciatum ?) 2, 4, 5, 11, 14, 17, 18, 19 Callithamnion baileyi 2, 4, 11, 14, 18, 19 Callithamnion tetragonum

, ceramium fastigiatum 3, 4, 5, 8, 10, 12, 14, 15, 17, 18, 19 i

Ceramium strictum 4, 8, 15, 18, 19 Ceramium mbrum 4,'18, 19 Spermothamnion turneri 4, 6, 11,.14, 17, 18, 19 Dasya pedicellata 1, 2, 4, 5, 6, 8, 10, 11, 12, 14, 15, 17, 19 i

• Species unambiguously identified throughout study.

164 I

l U

j l

__ ~

I j Chondria sp. 1, 4, 5, 17, 18, 19 j Polysiphonia denudata 4, 5, 8, 9, 10, 11, 14, 15, 16, 17,

! 18, 19 P. harveyi 1,2,4,5,6,8, 10, 11, 12, 14, 18,

19 1 P. subtilissima 4, 6, 12, 18  ;

} P. lanosa 4, 8, 14, 16, 17, 19 j P. nigra 4, 15, 17, 18 i Fungus (unidentified)

Foraminifera j Vorticellid sp.

i l Porifera

Haliclona loosanoffi 1, 2, 4, 5, 6, 7, 8,-10, 11, 12, 14, 15, 16, 17, 18, 19 l Nicrociona prolifera 1, 2, 4, 5, 6, 7, 8, 9, 10, 14, 16, j 17, 18, 19 i

i Hydrozoa

5, 14, 15, 18 Sarsia tubulosa

Hydractinia sp. 2,3,8 j Rathkea octopunctata 1, 5, 8, 14

Bcugainvillia sp.

1 Garveia groenlandica 6

Eudendrium sp. 18, 19 Clytia sp. 4, 14, 18 Obelia sp.

i Gonothyra Joveni 1, 2, 4, 5, 11, 12, 14, 15, 16, 18 4

Campanular2a sp. 1, 2, 3, 4, 5, 6, 8, 9, 10,.11, 12,.14, 15, 16, 17, 18, 19

] Sertularia argentea 1, 4, 18 i Schizotricha tenella 3, 4, 5, 8, 12, 15, 16, 17, 19 Anthozoa all j Nematostella vectensis ,

Diadumene leucolena all j Hallplanella luciae 1, 2, 3, 4, 8, 10,-11,'12, 13, 14 i Metridium sp.

j Sagartia modesta 3, 4 j Ctenophora -

l Beroe sp. 4, 5, 8, 10, 11, 12 i

3 i

165 i

t t

i 1

- - . + - - -~ .. , _ . - -

Turbe11 aria Bdelloura candida Probursa veneris 3, 4, 7, 12

.Stylochus ellipticus all Euplana gracilis all Prosthiostomum sp. 1 Nemertea Amphiporus sp. 4, 5, 7, 8, 12, 15, 16, 19 Nematoda all Entoprocta Barentsia sp. 2, 3, 4, 5, 6, 7, 8, 10, 11, 12, 14, 16, 17, 18, 19 I

Polychaeta Hypaniola grayi 12 Harmothoe sp. 1, 16, 18, 19 Lepidonotus squamatus 1, 2, 4, 5, 6, 7, 8, 11, 12, 14, 15, 16, 18, 19 Eteone sp. 18 Eumida sanguinea 1, 2, 4, 5, 6, 7, 8, 10, 11, 12, 14, 15, 16, 17, 18, 19 Eulalia viridis Phyllodoce sp. 7, 18 Gyptis vittata 1, 4, 5, 8, 9, 10, 11, 12, 14, 15, 16 17, 18, 19 Proceraea (=Autolytus) cornutus 5, 14, 18

Brania clavata all Parapionosyllis longic2rrata 4, 5, 10, 11, 12, 14, 15, 16, 18, 19 Streptosyllis sp. 4, 8, 19 Sphaerosy111s pirifera 4 Nereis arenaceodonta 1, 4, 8, 10, 16, 17 N. succinea all Platynereis dumerilii 1, 4 Nephtys sp. 1, 5, 8, 10, 12, 14, 15 Capite11a capitata 1, 6, 7, 12, 18 Polydora ligni all Polydora websteri Paraprionospio pinnata 1, 3, 5, 10, 17 Scolecolepides viridis 2, 4, 18 Streblospio benedicti 1, 3, 4, 10, 11, 12, 16 Sabe11 aria vulgaris 4, 8, 14, 15, 18

S. gracilis 4, 14 Marphysa sanguinea 12 166 I

I

Arabella iricolor 1, 5, 11, 12, 16 Notocirrus spiniferus Stauronereis rudolphi 8 Amphitrite ornata 12, 19 Loimia medusa 15, 18, 19 l Pista palmata 3, 4, 9, 11, 14, 16, 17 Fabricia Sabella 18 i

Potamilla neglecta 4, 12, 15, 18 P. reniformis 2, 5, 8, 10, 12, 14, 16 P. spathiferus 1 Sabella microphthalma all Hydroides dianthus all Ficopomatus

(=Nercierella) enigmaticus 2, 3, 4, 5, 6, 10, 14, 15, 17, 19 01igochaeta all Paranais litoralis Oligochaete spp.

Hirudinea sp.

Mollusca Littorina saxatilus 18, 19 Littorina littorea 2 Hydrobia truncata 2, 16 Bittium alternatum 2, 4, 5, 8, 11, 14, 15, 16, 17, 18, 19 Triphora nigrocincta Crepidula convexa 1, 2, 4, 5, 6, 8, 10, 11, 12, 14, 15 16, 17, 18 Eupleura caudata 4, 5, 8 Urosalpinx cinerea 2,_4, 5, 8, 11, 14, 15, 16, 17, 18, 19 ,

Thais haemastoni

. Anachis avara 4, 5, 15, 16 I Nitre 11a lunata 1, 4, 5, 10, 11, 12, 14, 15, 16, 17,

! 18, 19 i

Ilyanassa obsoleta 2, 4, 5, 10, 11, 12, 14, 15, 16, 17, 1 18, 19 Nassarius trivittatus 11, 18 Cylichnella bidentata 1 Odostomia bisuturalis 1, 2 Fargoa bartschi 1, 2, 4, 5, 6, 8, 12, 14, 15, 16, 17, 19 Stiliger fuscatus 'all Doridella obscura all Tene111a fuscata ,

Cratena pilata l

1 167

)

l

Aeolidia papillosa 1. 2,4,6,7,8, 10, 11, 14, 17, 18 19 Modiolus demissus 1,2,3,4,5,8, 10, 11, 12, 14, 17, 18

, Mytilus edulis 1, 4, 5, 6, 8, 9, 10, 11, 12, 14, 15 16, 17, 18, 19 Ostraea equestris 17 Mulina lateralis 19 '

Mya argenaria corbula contracta 2, 5, 18, 19 Bankia gouldi see text Teredo navalis see text Teredo bartschi see text Turtonia minuta 18, 19 Acarina sp. 7 Arthropoda callipallene brevirostris 1, 2, 4, 5, 8, 10, 11, 12, 14, 15, 16, 17, 18, 19 Callinidae spp.

Acartiidae spp.

Harpacticus sp. a11

Alteutha oblonga 4 Podon intermedius incidental on panels. Planktonic.

Ostracoda spp. 3, 4, 5, 6, 8, 10, 11, 14, 16, 17, 18 19 Balanus eburneus all Balanus improvisus all Balanus crenatus 16, 17, 18, 19 l Neomysis-americana 8, 14 Diastylis sculpta 17 Leptochelia savignyi 2, 3, 5, 7, 8, 10, 11, 14, 16, 17, 18 Jaera marina 18, 19 Erichsonella filiformis 4, 9, 14, 15, 18 E. attenuata 4, 12 Idotea baltica 2,4,5,8, 14, 17, 18, 19 l Edotea triloba 1, 4, 5, 8, 10, 11, 12, 14, 17, 18, 19 l

Cassidinisea lucifrons 1 Limnoria sp. 14, 15, 16, 17 Ampelisca abdita 1, 2, 4, 5, 9, 14, 15 l A. vadorum 1, 2, 4, 5, 8, 14,^16 Amphithoe valida 1, 2, 4, 5, 6, 8, 9, 10, 11, 14, 15, ,

16, 17, 19 ~

l Cymadusa compta 1, 2, 4, 6, 8, 9, 10, 11, 12, 14, 15 '

16, 17, 18, 19 Lembos websteri 15 168

, L. saithi 17 Microdeutopus gry110talpa -all

]

Pseudunciola obliquus 4

Batea catherinensis 4, 5, 8, 10, 14, 15, 16, 17 Calliopus laeviusculus 14, 17, 18, 19 i corophium spp. all Erichthonius brasiliensis 1, 2, 4, 5, 8, 12, 14, 15, 18, 19 Erichthonius nzbricornis 4 Unciola serrata 12 Siphonoecetos smithianus 4 Gammarid spp. all

. Elassopus levis 1, 2, 3, 4, 5, 6, 8, 9, 10, 11, 12, 14,

15, 16. 17, 18, 19 Gammarus palustris 5, 19 G. mucronatus all G. Oceanicus 7, 19 G. lawrencianus t 7, 19 Melita nitida 1, 2, 3, 4, 5, 6, 7, 8, 10, 11, 12, 14, 15, 16, 17 Nicroprotopus raneyi 1, 2, 5, 8, 16, 17, 18, 19 ,

Jassa falcata 2, 3, 4, 5, 6, 8, 9, 10, 11, 12, 14, 15, 16, 18, 19

! Lysianopsis alba 1, 4, 5, 8, 10, 11, 14, 15,.16, 18 Syrchelidium americanum 9 j Parametopella cypris 5, 14, 18 Stenothoe minuta 4, 5, 6, 7, 8, 9, 10, 11, 12, 14, 15, i 16, 17, 18, 19 i Capre11a penantis 4, 5, 8, 18, 19 Paracaprella tenuis 1, 2, 4, 5, 6, 7, 8, 9, 10, 11, 12 i 14, 15, 16, 17, 18, 19 Paleomonetes sp. all

P. pugio 5 t P. vulgaris 11, 19

! Crangon septemspinosus 8 Callinectes sapidus 3, 8, 10, 19

Carcinus maenas 18 Cancer irroratus 18 C. bovenlis 18 Neopanope sayi 1, 4, 5, 8, 10, 11, 14, 15, 16, 17, 18, 19 Panopeus herbstil 1, 4, 8, 17 Rhithropanopeus harrisii 1, 2, 3, 10, 16, 17 Libinia emarginata 5, 18, 19 l Miscellaneous Phyla l .Collembola spp. 1, 5, 12,.19 l

l Chironomidae 1, 3, 4, 7, 10, 12, 17.

I l

i 169 l

I i

Sipuncilid spp. 1, 2, 4, 5, 6, 10, 11, 12, 15, 16 Echiurid spp. 12

, Ectoprocta Amanthia sp. 2,4,5,8 Bowerbankia gracilis 1, 2, 3, 6, 7, 8, 11, 12, 16, 19 Aeverillia armata 1, 5, 8, 11, 12, 14, 19 Membranipora sp. all Electra sp. (hastingsae?) all Bugula turrita 1, 4, 5, 6, 7, 8, 14, 15, 16, 17, 18, 19 Schizoporella unicornis 5, 8, 14, 15, 16, 17, 18, 19 Cryptosula pa11asiana 16, 18, 19 Hippoporina sp.

Echinodermata Asterias forbesi 4, 14, 15, 18, 19 Hemichordata Saccoglossus kowalevskii 1,2,4 Tunicata

, Perophora sp. 5 Botryllus schlosseri all '

Molgula manhattensis all styella puttita 4, 19 Vertebrata Anguilla rostrata 2 Opsanus tau 9, 11, 16

~

B1ennius marmoreus Tautogolabzus adspersus Gobiasoma bosci 1, 6, 9, 11, 12, 14, 15, 16 I

l l

170 i

.. . . =__ _ - . .. . . _ = _ _ . _ _ . - .

2 d

DISTRIBUTION LIST DISTRIBUTION CATEGORY: RE Supplemental Distribution: Part A Mr. Richard Banagardt

! Dick's Landicag Holly Park Bayville, New Jersey 08721 Mr. William Campbell l P. O.-Box 668 108 Long John Silver Way Waretown, New Jersey 08758 Mr. Stan Cottrell North Harbor Road Waretown, New Jersey 08758 Mr. Wilson T. Crisman

901 Hudson Street Hoboken, New Jersey 07030 Mr..and Mrs. Thomas Gilmore t

20 Dock Ave., Box 205 E, R.R.I.

I Waretown, New Jersey 08758 Mr. Walter Holzman i 1915 Beach Blvd.

Forked River Beach, New Jersey 08731 Mr. Charles Kochman Compass Road Waretown, New Jersey 08758 i

Mr. Ed Sheridan 1108 Leilani Drive Forked River, New Jersey- 08731 l

Mr. Gustav Walters 100 Manhattan Avenue, Apt. 706' Union City, New Jersey 07087 l

l l

1711

I Part B Mr. Edward Wheiler 16 River View Drive, P.O. Box 642 Forked River, New Jersey 08731 1 Mr. John Turner i

19 Jolly Roger Way Waretown, New Jersey 08758 Battelle Columbus Laboratories Clapp Laboratories Duxbury, Massachusetts 02332 Mr. Michael Roche Supervisor of Environmental Science

, Jersey Central Power and Light Co.

Madison Ave. at Punchbowl Road Morristown, New Jersey 07960 Dr. Glenn Paulson Asst. Commissioner for Science Dept. of Environmental Protection State of New Jersey P.O. Box 1390 Trenton, New Jersey 08625 Mr. Alan R. Hoffman Lynch, Brewer, Hoffman & Sands

• Ten Post Office Square '

Suite 329 Boston, Massachusetts 02109 ,

1-Mr. John Makai Nacote Creek Research Station Star Route Absecon, New Jersey 08201 Mr. Steve.Lubow NJDEP-Division of Water Resources P.O. Box CN-029 Trenton, New Jersey 08625 Dr. Harry L. Allen US EPA Region II

, 26 Federal Plaza i Room 832 l

New York, New York. 10007 172 l

l. '

Dr. Joan Stra2d Ecosysters Department Battelle Northwest Lab )

Richland, Washington 99352 Dr. D. Heyward Hanilton, Jr.

EV-34, GTN U.S. Dept. of Energy Washington, D.C. 20545 l

173

L REFORT NW8E9 Mssirecf by DOC /

$,",,crom33s u.s. mucLEAa cEcutAroav commissiOu BIBLIOGRAPHIC DATA SHEET NUREG/CR-3446 4 TITLE AND SUBTlTLE LAdd Volume No.. of wormronol 2. ILeave D1mkl Ecological Studies of Wood-Boring Bivalves in the Vicinity

, of the Oyster Creek Nuclear Generating Station, Final 3. RECIPIENT'S ACCESS 40N NO.

Report: September 1, 1976 - December 31, 1982

7. AUTHORtS) 5. DATE REPORT COMPLETED MON TH l YEAR K. E. Hoagland August 1983 .

9 PERFORVING ORGANIZATION N AVE AND MAILING ADDRESS (lactu* leo Codel DATE REPORT ISSUED -

Department of Malacology uo~ m lvEAR Academy of Natural Sciences of Philadelphia October 1983 19th and the Parkway 6 (te e u a*i Philadelphia, PA 19103 8 (Leave Nmkl

12. SPONSORING ORGANIZ ATION NAME AND M AILING ADDRESS (factue to Coe '

4 Division of Health, Siting and Waste Management Office of Nuclear Regulatory Research ,, gy go.

U.S. Nuclear Regulatory Comission Washington, DC 20555 B8138

13. TY PE OF REPORT PE RIOD COV E Rf D t#4rtussve dates)

Final Report September 1, 1976 - December 31, 1982 15 SUPPLEMENTARY NOTES 14. (Leave n/mel

16. ABSTR ACT (200 words or less' The species composition, distribution, and population dynamics of wood-boring bivalves were studied using wood test panels at 20 stations in the vicinity of the Oyster Creek Nuclear Generating Station, Barnegat Bay, NJ. Physiological tolerance s of three teredinid species were investigated in the lab and correlated with field values of temperature, salinity, silt, precipitation, and plant operations. The interaction of boring and fouling organisms was examined.

There is a definite correlation between the operation of the power plant and teredinid outbreaks. Increased salinity and water flow as well as temperature are responsible.

After 1976, most of the damage in Oyster Creek was done by the introduced subtropical species Teredo bartschi. It can respond faster than native species to environmental change.

l Although Oyster Creek contributed larvae to neighboring parts of Barnegat Bay, its role as a breeding ground was limited. Some elements of the fouling community may be antagonistic tc shipworm growth. Fouling was increased in both biomass and species richness in Oyster i Creek when compared with creek controls, but the fouling community in Oyster Creek was les s

, stable than that in other areas. Lower salinity limits fer the teredinids were within ae salinity range found in Oyster Creek but not within the range of the control creeks.

I conclude that arrival of the introduced species exacerbated the wood destruction nrnence in Ovster Creek and also in Forked River.

17. KEY WORDS AND DOCUMENT ANALYSIS 17a DESCUPTORS Thermal Effluents Shipwoms Oyster Creek Teredo bartschi l Teredo navalis Bankia gouldi I ?b. IDE N TIFIE RS OPEN E N DE D TE RVS 18 AVAILABILITY STATEMENT 19 SE CURITY CLASS (Th,s reporrl 21 NO. OF PAGES Unclassified Unlimited M ync'N's*sM'e*[*#'## s N RC FORM 335 ell ets

UNITED STATES '

NUCLEAR REGULATORY COMMISSION ostGhs$s'*Io o WASHINGTON, D.C. 20555 f,7;"j c n .m r .. an OFFICIAL BUS: NESS PENALTY FOR PRfvATE USE, $330 .

?

?

O O

O 120555078877 1 LANIRE US NRC O m

ADM-01V UF TIDC POLICY C PUB MGT BR-PDR NUREG $

W-501 OC 20555 m W A SH INGT ON Oo

<a N

m.

3a O

m m*

M PC a 2

C O

r- -

m O-me 2

m a 2o d

z O

Cn H

d O

zj S

1 s

.