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Fishery Bulletin 101(3) 



labia and untrawlable habitats. Flatfish were more than 

 ten times as abundant in the trawlable habitat samples, 

 whereas rockfish as a group were over three times as 

 abundant in the untrawlable habitat samples. Silvergray, 

 quillback, redstripe, and yelloweye rockfish were observed 

 in the untrawlable habitat but not in any of the trawlable 

 habitat samples. 



We know of no visual-transect data comparable to 

 that presented here for fish abundances off Washington. 

 However, previous habitat specific studies in other areas 

 have also reported differences in species composition and 

 fish densities between low relief (trawlable) and highly 

 rugose (untrawlable) habitats. Richards (1986) conducted 

 a submersible study in the Strait of Georgia, British Co- 

 lumbia (21-140 m), and observed that the distribution of 

 greenstriped, quillback, and yelloweye rockfish varied by 

 depth and bottom type. Greenstriped rockfish were most 



abundant in fine sediment habitats, such as mud and 

 cobble terrain. Quillback rockfish were most abundant 

 in complex habitats, and yelloweye rockfish had higher 

 densities in wall and complex habitats than in fine sedi- 

 ment habitats. In the coastal fjord of Saanich Inlet, British 

 Columbia (21-150 m), Murie et al. ( 1994) also reported that 

 quillback rockfish density was higher in areas of complex 

 or wall habitat, compared to areas of sand-mud habitat. 

 Additionally, tiger, copper (S. caurinus), yellowtail, and 

 yelloweye rockfish were observed only over complex or 

 wall habitats, and gi-eenstriped rockfish were seen mostly 

 over sand-mud habitat. Using sunken gill nets to sample 

 trawlable and untrawlable habitats off Vancouver Island, 

 B.C. (198-311 m in depth), Matthews and Richards (1991) 

 reported difTerences in species composition between traw- 

 lable and untrawlable areas and higher species diversity 

 in trawlable habitat. Major species on trawlable bottom 



