en 



UJ 

 CD 



B: 



^4 



_, 



STA. 5-1 

 384(11) 



R 



STA.5-3 

 80 (8) 



Fr=r- 



-R 



STA 5-2 

 580 (22) 



Fh- 



STA. 7-2 

 207 (4) 



R 



LENGTH 



Mussels may show sublethal effects from very low concentra- 

 tions of hydrocarbons. Gilfillan (1975) found that as little as 1 ppm 

 of the water soluble fraction of crude oil increased respiration while 

 decreasing feeding and assimilation of mussels. Gonzalez et al. 

 (1979) found a decrease in the filter-feeding rate of mussels at con- 

 centrations of water-accommodated fraction of No. 2 fuel oil as 

 low as 10 ppb. 



It seems likely that exposure to gasoline in the areas sampled 

 (0.8 and 1.6 km from the grounding and at a depth of 10 m) was 

 below acutely toxic levels. Reduced filtering rate or shell closure 

 could also have reduced effective exposure and toxic effects. 



Because of the ability of mussels to accumulate hydrocarbons, 

 more extensive collections and analysis may have indicated the 

 horizontal and vertical distribution of gasoline in the spill area. In 

 retrospect it seems that an opportunity was lost to observe the ef- 



Figure 3-3. — Size class distributions of bine mussels, Mytilus edulis, from benlhic 

 grab samples, "dappers" are the shells of dead animals which are still attached. 

 Total number of live and clapper mussels (in parentheses) are shown under sample 

 number. Station locations are indicated in Figure 3-1. 



INTERVAL (cm) 



Table 3-2.— Bent hie fauna recovered from Shipek grab samples in the vicinity of Watch Hill Reef {Ocean 250 spill). 



Station-grab 



2-1 



2-2 



2-2 



5-1 



5-2 



5-3 



6-1 



6-2 



6-3 



7-1 



7-2 



7-3 



8-1 



8-3 17-1 17-2 17-3 



Mollusca: 



I a nana heros 



I unarm triseriata 



Mitrella lunula 



Nucula annulata 



Mytilius edulis 



Musculus sp, 



Crenelta descussata 



Aslarie undaia 



Astarte castanea 



Crassinella mactracea 



Cyclocardia borealis 



Arctica islandica 



Cerastoderma pinnulalum 



Spisula solidissima 



Tellina agilis 



Periploma sp. 

 Crustacea: 



Harpacticoid copepods 



Oslracoda spp. 



Chiridolea tuftsi 



Erichsoniella filiformis 



Tanaidacea sp. 



Elasmopus levis 



Maera danae 



Sympleustes glaber 



Parametopella cypris 



Ampithoe sp. 



Acanthohaustorius intermedius 



Protohaustorius wigteyi 



Bathyporeia parkeh 



Phoxocephalus holbolli 



Paraphoxus epistomus 



Lysianopsis alba 



Microdeulopus sp. 



Unciola irrorata 



Erichthonius sp. 



Corophium sp. 



Byblis serrata 



Ampelisca vadorum 



Proboloides holmesi 



Pagurus longicarpus 



Cancer irroratus 

 Polychaeta: 



Lepidonotus squamatus 



Harmolhoe extenuata 



384 580 80 



10 



1 

 10 



270 



43 



1 





3 







1 



5 







1 



4 







1 









1 



1 



1 



2 





9 



2 



1 



1 









2 4 

 2 



3 4 



1 



1 1 



3 



1 



2 

 1 



3 

 2 



1 1 



1 1 

 1 2 



2 



1 





1 



1 

 1 



2 1 



4 



9 10 



1 4 



1 



27 



18 



