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Fishery Bulletin 97(4), 1999 



In 1976, a total of 39,927 fish comprising at least 

 28 species were collected from 131 seine sets (green- 

 ling, Hexagrammidae, and sculpins, Cottidae, were 

 not always identified to species; Blackburn et al., 

 1980; Table 1). To compare these data statistically 

 with 1995-96 information, sculpin and greenling 

 were combined into two general categories. By num- 

 ber, sand lance (81%) and herring (12'^() accounted 

 for more than 93 9( of the 1976 catch. Four of the five 

 species that dominated 1976 catches also dominated 

 the 1995-96 catches (sand lance, herring, Dolly 

 Varden, and pink salmon), and sand lance and her- 

 ring were the two most abundant fish caught during 

 both study periods. In 1976, only four lO.OV'c) fish 

 were gadids (3 saffron cod, Eleginus gracilis; and 1 

 Pacific cod). By 1995-96, gadids (Pacific cod; saffron 

 cod; Pacific tomcod, Microgadiis proximus; and wall- 

 eye pollock) were more numerous on the basis of 

 catch-per-unit-of-effort (CPUE, defined as catch-per- 

 individual-seine) by 1-3 orders of magnitude and had 

 increased in frequency of occurrence by more than 

 300Vi (Table 1 ). Furthermore, Pacific cod was a domi- 

 nant species in the 1995-96 catches. Similar in- 

 creases in CPUE or frequency of occurrence were 

 apparent for sockeye and chum salmon (O. ncrka. 



O. keta ), three sculpin species (silverspotted sculpin, 

 Blepsias cirrhosus; buffalo sculpin, Enophrys bison; 

 warty sculpin, Myoxocephalus verrucosus). Pacific 

 sandfish, two prickleback species ( slender eelblenny, 

 Lumpenus fabricii; daubed shanny, L. maculatus), 

 lobefin snailfish (Liparis greeni). sablefish {Anoplo- 

 poma fimbria ). and a flatfish species (Hippoglossoides 

 elassodon ). Marked declines only occurred in catches 

 of masked greenling (Hexagrammos octogrammus), 

 coho salmon (O. kisutch ), and longsnout prickleback 

 (Lunipcnella longirostris). Differences between 1976 

 and 1995-96 catches were significant on the basis of 

 change in CPUE (Mann-Whitney rank sum test; 

 /=1339.5, P=0.007), percent composition (/=1373.0, 

 P=0.018), and frequency of capture (/= 1398.0, P=0.033). 

 Changes in fish abundance were accompanied by 

 changes in community diversity (Table 2). The 

 Shannon-Wiener index (Hi was greater in 1995-96 

 than in 1976, refiecting the large increase in gadid 

 species during the 1990s (accounting for two thirds 

 of the difference in H). Species richness (D) was also 

 higher in 1995-96, compared with 1976. This differ- 

 ence resulted from the fact that four species repre- 

 sented 92^/^ of the total 1995-96 catch. In contrast, 

 only two species accounted for 93''^ of the 1976 catch. 



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