of gasoline components by fish habitating the area at the time of the 

 spill. 



Conclusions. — It would be difficult to interpret the rather 

 anomalous, general cytological findings reported here for the 

 samples taken 2 and 4 d after the spill, except in terms of direct 

 exposure of spawned eggs to the spilled gasoline. It is not surprising 

 that qualitative effects are found on fish eggs that are not simply 

 explainable on the basis of natural variables as temperature and 

 salinity. Chemical analyses of the water column and of plankton 

 and macrobenthos collected during the period, from just after the 

 spill to 4 d after the spill, indicated both the presence of gasoline 

 fractions in the water and its uptake by shellfish (Lake et al., see 

 section 2.2) and plankton (Hoffman and Quinn, see section 2.3) 

 which, of course, would include the fourbeard rockling and 

 yellowtail flounaer eggs. 



Low number of eggs sampled on postspill day 2 may be 

 attributable to their gross deterioration and settling out of the water 

 column. It is difficult to suppose that the pathologies attributed to 

 direct contact with the gasoline did not increase mortality rates of 

 the fish eggs as sampled 2 and 4 d after the gasoline spill. 



The fact that about 40% of the eggs were moribund as long as 

 25 d after the spill and that their development rate, as measured by 

 mitotic index, was depressed over the 2 and 4 d samples could be 

 interpreted as meaning that the gasoline spill had little to do with 

 the overall estimates of egg mortality. However, it is likely that 

 gasoline components taken up by the fourbeard rockling and 

 yellowtail flounder habitating the area at the time of the spill 

 (Boehm and Barak, see section 2.4) would have affected the quality 

 of the eggs subsequently spawned and sampled in the plankton 25 d 

 after the spill. Unfortunately, no samples of these fish or their 

 spawned eggs were available from the spill area prior to the spill. 

 Also, other contamination in water and biological samples (see 

 papers, this volume) poses problems in the effort to estimate any 

 quantitative impact of the spill. 



Yellowtail flounder eggs sampled in the spill area appeared 

 overall to be doing less well than eggs of the fourbeard rockling. 



The cytological study of these eggs sampled in the plankton 

 from the area of the gasoline spill and consideration of the 

 significance of the results provide insights that could be useful in 

 planning responses to future spills. 



3.5 Summary 



Thirty-five grab samples were taken at six stations within 1.6 

 km of the spill site. The sandy sediments reflected strong wave and 

 tidal currents in the area. Silty sediments were found under dense 

 clumps of blue mussels. Fauna! diversity and density was low except 

 in the mussel clumps. However, no recently dead or abnormal 

 mussels or infauna were detected even though gasoline components 

 had been found in other bivalves in the area and no changes in the 

 makeup of faunal assemblages were detectable from the sample 

 counts. 



Similarly, analysis of the zooplankton community at 4 d and 3 

 wk postspill indicated no discernible impact of gasoline, nor was 

 there any visible evidence of damage. Changes that occurred from 

 the 4 d postspill period to the second sampling period were 

 attributed to the patchy nature of plankton and to population 

 blooms rather than to the effect of gasoline contamination. 



Bouyant eggs of the fourbeard rockling and yellowtail 

 flounder, sampled 2 and 4 d after the gasoline spill were partially 

 collapsed, had chorion (outer egg membrane) lesions and unusual 

 embryo or egg pathologies. Only 12 eggs, all fourbeard rockling. 



were collected 2 d after the spill. These were in very early develop- 

 ment stages and, on the basis of cytological criteria, were all 

 moribund. Four days after the spill, 84 fourbeard rockling eggs at 

 about the same development stages were close to 60% moribund, 

 using the same criteria. Twenty-five days after the spill moribundity 

 of the 79 fourbeard rockling eggs collected at the same stage was 

 about 40%. In addition, mitotic index, taken as an indicator of 

 development rate and embryo well-being, was depressed over that 

 of earlier samples. Only 16 yellowtail founder eggs were collected in 

 toto over all three sample days, and at somewhat later development 

 stages expected to show lesser mortality than earlier stage fourbeard 

 rockling eggs, however, all but three were moribund. 



LITERATURE CITED 



BENYON, L. R. 



1967. The Torrey Canyon Incident: a review of events. British Petroleum 

 Company, 25 p. 

 BIERNBAUM, C. K. 



1975. Benthic amphipoda of Fishers Island Sound, Connecticut - An analysis 

 of distribution and association in response to sedimentary factors. Ph.D. 

 thesis, Univ. Connecticut, 230 p. 

 BIGELOW, H. B., and W WELSH. 



1924. Fishes of the Gulf of Maine. Bull. U.S. Bur. Hsh. 40(1), 567 p. 

 (Doc. 965). 

 BLUMEK, M., G. SOUZA, and J. SASS. 



1970. Hydrocarbon pollution of edible shellfish by an oil spill. Mar. Biol 

 5:195-202. 



BOEHM, P. D„ and J. G. QUINN. 



1977. The persistence of chronically accumulated hydrocarbons in the hard 

 shell clam Mercenaria mercenaria. Mar. Biol. 44:227-233. 

 BROCKSEN, R. W., and H. T. BAILEY. 



1973. Respiratory response of juvenile Chinook salmon and striped bass ex- 

 posed to benzene, a water-soluble component of crude oil. Proceedings of 

 a Joint Conference on Prevention and Control of Oil Spills, p. 783-792. 

 API, EPA, USCG, Wash., D.C. 

 BUGBEE, S. L., and C. M. WALTER. 



1973. The response of macroinvertebrates to gasoline pollution in a moun- 

 tain stream. Proceedings of a Joint Conference on Prevention and Con 

 trol of Oil Spills, p. 725-732. API, EPA. USCG. Wash. D.C. 

 BUKNS, K. A., and J. L. SMITH. 



1977. Distribution of petroleum hydrocarbons in Westport Bay (Australia): 

 Results of chronic low level inputs. In D. A. Wolfe (editor), Fate and 

 effects of petroleum hydrocarbons in marine ecosystems and organisms, 

 p. 442-443. Pergamon Press, N.Y. 

 CRAPP, G. B. 



1971. The ecological effects of stranded oil. In E. B. Cowell (editor), The 

 ecological effects of oil pollution on littoral communities, p. 181-186. Inst. 

 Petroleum, Lond. 



DIMOCK, C. W„ J. L. LAKE, C. B. NORWOODS, R. D. BOWEN, E. J. 

 HOFFMAN, B. KYLE, and J. G. QUINN. 



1980. Field and laboratory methods for investigating a marine gasoline 

 spill. Environ. Sci. Technol. 14:1472-1475. 

 DiSALVO, L. H., H. E. GUARD, and L. HUNTER. 



1975. Tissue hydrocarbon burden of mussels as potential monitor of en- 

 vironmental hydrocarbon insult. Environ. Sci. Technol. 9:247-251. 

 FAGER, E. W., and J. A. McGOWAN. 



1963. Zooplankton species groups in the North Pacific. Science 

 140:453^60. 

 GILFILLAN, E. S. 



1975. Decrease of net carbon flux in two species of mussels caused by ex- 

 tracts of crude oil. Mar. Biol. 29:53-57. 

 GONZALEZ, J., D. EVERICH, J. HYLAND, and B. MELZIAN. 



1979 The effects of No. 2 heating oil on filtration rate of blue mussels, 

 Mytilus edulis. Proc. Symp. Adv. Mar. Environ. Res. 112-121. 

 GROSS, P., and J. MATTSON. 



1977. Investigations of biological processes and effects. In P. Gross and 

 J. Mattson (editors), The Argo Merchant oil spill, a preliminary scientific 

 report, 322 p. NOAA Spec. Rep., Wash., D.C. 



HESS, W. N. 



1978. Biological observations. In W. N. Hess (editor), The Amoco Cadiz 

 oil spill, a preliminary scientific report, 283 p. NOAA/EPA Spec. Rep., 

 Wash., D.C. 



29 



