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Fishery Bulletin 97(4), 1999 



Discussion 



Nearshore fish communities 



The overall composition of beach seine catches did 

 not differ between 1995 and 1996, and community 

 indices were also similar between years. This gives 

 us confidence that changes in community composi- 

 tion observed between 1976 and 1995-96 reflected 

 decadal-scale variability rather than just annual 

 variability. The increase in beach seine CPUE be- 

 tween 1976 and 1995-96 may have also been real, 

 but we have less confidence in this result because 

 beach seines were deployed dloser to shore in 1976 

 (10 m) than in 1995-96 (25 m), and this difference 

 might have influenced catch rates. The most dra- 

 matic difference between decades was in catches of 

 gadids (including pollock). Few were caught in the 



whole of lower Cook Inlet during 1976, when gadids 

 represented only 0.2*^^ of the total catch (85 individu- 

 als in 262 seines; Blackburn et al., 1980). The 1000- 

 fold increase in gadids that we observed in the mid- 

 1990s parallels a similar increase in abundance of 

 gadids in offshore shrimp trawls in Cook Inlet 

 (Bechtol, 1997) and the Gulf of Alaska (Piatt and 

 Anderson, 1996; Anderson et al. , 1997 ). Similarly, the 

 increase in pleuronectids and salmonids that we ob- 

 served in Kachemak Bay between 1976 and 1995- 

 96 was paralleled in the Gulf of Alaska in shrimp 

 trawls ( Anderson et al. , 1997 ) and commercial salmon 

 catches (Francis and Hare, 1994), respectively. 



Interdecadal changes in abundance of these fishes 

 are probably related to large-scale climate changes 

 in the North Pacific, but causal mechanisms are un- 

 clear (Francis et al., 1998). Water temperatures in 

 the northern Gulf of Alaska changed from being 



