FISHERY BULLETIN: VOL. 85, NO. 3 



longed dietary restriction to one or several oppor- 

 tunistic prey could compromise the health of the 

 fishes. 



In summary, all three fishes exhibited some 

 degree of selective predation on Capitella spp. 

 based on both number and size of these prey. Di- 

 etary contribution by these polychaetes was 

 greatest at night for all three fishes, suggesting 

 that Capitella spp. may become more accessible to 

 predators at night. Predation on Capitella spp. 

 allowed English sole to alter its normal diurnal 

 feeding behavior and forage successfully at night. 

 Finally, this study supports the hypothesis that 

 some demersal fishes can exploit opportunistic 

 prey in disturbed habitats. 



ACKNOWLEDGMENTS 



We thank M. J. Allen, J. N. Cross, and E. W. 

 Hogue for their comments on the manuscript. 

 This study was supported by the Office of Marine 

 Pollution Assessment of the National Oceanic 

 and Atmospheric Administration (Contract 

 NA80RAD00050). A. J. Mearns was the Project 

 Officer. This study is part of a dissertation sub- 

 mitted to the School of Fisheries of the University 

 of Washington (Seattle, USA) in partial fulfill- 

 ment of a Ph.D. degree for D. S. Becker. 



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