512 



Fishery Bulletin 91(3). 1993 



predation; or to what degree are the overall predatory 

 pressures on herring affected indirectly by seal preda- 

 tion on other herring predators such as hake, salmon, 

 and lingcod? Such a bioenergetics community model 

 will need to incorporate not only data on the size of 

 prey consumed, which can be obtained from a more 

 detailed analysis of scat contents (e.g., Bailey and 

 Ainley, 1982; Antonelis et al., 1983), but also the dy- 

 namics and compensatory and depensatory mechanisms 

 of population regulation of prey populations. 



Acknowledgments 



I would like to extend special gratitude to the late M. 

 Bigg for his contributions to the investigations under- 

 lying this synthesis. I am also grateful to L. Barrett- 

 Lennard, G. Ellis, C.-E. Neville, T. Pawloski, H. 

 Reisenleiter, and N. Thompson for their assistance in 

 the field; to S. Crockford and R. Wigen for identifying 

 prey remnants in scats; to S. Innes and D. Lavigne for 

 helpful discussions on phocid energetics; to E. 

 Warneboldt for drafting the illustrations; and to T. 

 Beacham, M. Bigg, and anonymous reviewers for con- 

 structive comments on earlier drafts of the manuscript. 



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