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Fishery Bulletin 100(3) 



more abundant in the eastern GOA, but generally had 

 a broad geographic distribution. The deep-water species 

 included several rockfish species, rex sole iGlyptocephalus 

 zachiriis), Dover sole {Microstomiis pacifictis), sablefish, 

 and myctophids. The alongshore distribution of CPUE 

 suggests that many species displayed local maxima in 

 biomass on the scale of 100-200 km (Fig. 8). The first axis 

 was negatively correlated with a group of shallow-water 

 species that were typically more abundant in the west- 

 ern GOA. The shallow-water group included a number of 

 flatfish species, gadids, and sculpins. Many of the shallow 

 water species had pronounced peaks in biomass at the lon- 

 gitude of Kodiak Island (km 1400-1700) and between the 

 Shumagin Islands and Sanak Island (km 2000-2200). 



The second axis was positively correlated with a "shelf 

 break" group. Most of the species in this group had a 

 pronounced peak in biomass near 200 m and were found 

 primarily in the eastern GOA (Fig. 9). The group included 

 a number of rockfish species, as well as lingcod iOphiodon 

 elongatus), petrale sole (Eopsetta jordani), and slender 

 sole {Lyopsetta exilis). Species that were negatively or 

 positively associated with the third axis (not shown) were 

 not differentiated along gradients of depth and alongshore 



distance, suggesting that the third axis, which accounted 

 for 14% of the overall variation, was related to other, un- 

 identified gradients. 



Finally, we examined trends in species composition 

 over the 12-year period from the first survey in 1984 

 to the most recent survey in 1996 in more detail based 

 on the NMDS ordination of species CPUEs averaged by 

 stratum (Fig. 7). Although the individual indices of species 

 composition were not significantly different among years 

 (Table 5), a canonical correlation between the ordination 

 axes and time (survey years) indicated a highly significant 

 trend (P<0.001) in species composition. The linear combi- 

 nation of ordination axes that maximized the correlation 

 with survey year was used as an index for the trend in 

 species composition ("time index"). The index increased 

 in most areas and depth strata between 1984 and 1996. 

 Eight species that were positively correlated with the 

 time index showed significant and increasing trends in 

 either CPUE-where-present or frequency of occurrence for 

 at least two area-depth stratum combinations (Fig. 10). 

 Skates were most strongly associated with the index and 

 showed a widespread increase in CPUE-where-present 

 and frequency of occurrence, particularly in the Chirikof, 



