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Fishery Bulletin 91(4), 1993 



regions than those for spring cruises (Table 2). Several 

 patterns are evident in significant test statistics for the 

 autumn cruises. Biomass CPUE for eight species showed 

 highly significant differences for both pre- and post- 

 dumping periods. These species were silver hake, red 

 hake, summer flounder, goosefish, black sea bass, but- 

 terfish, longfin squid, spiny dogfish, and all species. 

 Fewer significant differences were observed in the num- 

 ber of CPUE. No distinct pattern was obvious for spring 

 cruises. Only silver and red hake CPUE showed signifi- 

 cant test statistics for both periods. Scup, American lob- 

 ster, and sea scallop CPUE showed generally lower val- 

 ues that were not significantly different. There was a 

 significant difference between north and south in num- 

 ber of species for autumn cruises in both the pre- 

 dumping and post-dumping periods (Table 2). 



Interpretation of these significant spatial differences 

 requires special caution. In 1982, the first year for 

 which data were used in this study, populations were 



not of comparable size in the north and south regions. 

 One must consider how populations of unequal size 

 could have accommodated differing environmental per- 

 turbations and fishing pressure in the north and south 

 regions. Silver hake, red hake, butterfish, and spiny 

 dogfish indices were highest. Goosefish and American 

 lobster indices were lower overall, but higher in the 

 north than in the south, while scup were higher only 

 in the south. Longfin squid indices were consistent 

 with its migratory pattern (concentrated in the south 

 in spring and in the north in autumn) (Tables 4-7). 

 Test statistics of all eight species were significantly 

 different between north and south (Table 2). 



Test statistics were tabulated for species CPUE be- 

 tween north and south, and for species abundance indi- 

 ces, including all species in the north and south regions 

 for individual cruises, but are not presented here. This 

 information supplemented the findings from collective 

 cruises (Tables 2, 4-7). Indices from individual cruises 



