596 



Fishery Bulletin 91(4), 1993 



□ 



Figure 1 



Location of the 106-mile dumpsite and strata used in Northeast Fisheries Science Cen- 

 ter bottom trawl surveys (1963 to present). The potential area of influence (PAIl by 

 sewage sludge dumping is within the dashed line, which is adapted from Biasagni 

 (1983). 



erel {Scomber scombrus) embryos developing in sur- 

 face waters about the 12-MDS ( i974-1978) had greater 

 mortality and gross malformation, more mitotic ab- 

 normality and mitotic inhibition than those in less con- 

 taminated bight areas, and this was linked to site con- 



tamination (Chang and Longwell, 

 1984; Longwell, 1988; Longwell et 

 al., 1992). 



Unlike the 12-MDS in the New 

 York Bight apex and the sewage 

 outfalls in southern California, 

 the 106-MDS is situated in a 

 physically dynamic zone charac- 

 terized by periodic shifts and 

 overturns in water masses. The 

 toxic water is rapidly diluted and 

 dispersed. This may diminish the 

 impact of dumped waste and as- 

 sociated chemical contaminants, 

 but it also makes determination 

 of any adverse effects on the re- 

 source more difficult to study 

 than those associated with sew- 

 age sludge dumping in shallow- 

 waters. Still, the economic value 

 of the nearby fisheries warrants 

 some effort at directly measur- 

 ing potential adverse impacts of 

 the 1986-92 sludge dumping on 

 the fishery resource in the vicin- 

 ity of the 106-MDS. 



The study reported here is an 

 attempt to determine if any 

 change in fishery resource abun- 

 dance on the adjacent continen- 

 tal shelf and slope could be de- 

 tected after sewage sludge 

 disposal commenced at the 106- 

 MDS in March 1986. Although 

 ocean dumping is now banned, 

 this period of sludge dumping in 

 the deep ocean provides an in- 

 teresting case study for consid- 

 eration of effects of ocean pollu- 

 tion in general on economically 

 important fishery resources. This 

 analysis is of potential interest 

 in respect to any future recon- 

 sideration of ocean dumping. 

 There are no prior population 

 level studies on abundance 

 changes in marine fishes associ- 

 ated with the sewage sludge 

 dumping in deep ocean waters. 

 The general null hypothesis 

 that was tested is that no change in resource species 

 abundance and composition was coincident with sew- 

 age dumping at the deepwater 106-MDS during the 

 period 1986-90. Assessments were made of temporal, 

 spatial, and seasonal differences in 11 individual finfish 



DEPTH ZONES ( M ) 



27-51 

 56-110 

 111-163 

 >183 



