Fritz and Brown: Interactions between the Pacific cod fishery and Steller sea lions 



515 



The annual harvest rate of BSAI cod in 2001 was es- 

 timated to be approximately 11% (Thompson and Dorn, 

 2002). The total catch of cod in the BSAI through 24 

 March represented only 44% of the total catch of Pa- 

 cific cod in 2001. Therefore, the harvest rate through 

 24 March should only have been 44% of 11%, or about 

 5%. The local harvest indices estimated in the present 

 study, which ranged from 26% to 80%, were five to 16 

 times greater than that on the BSAI Pacific cod stock 

 as a whole in 2001. Much of the area used by the fish- 

 ery is designated as critical habitat for the endangered 

 Steller sea lion, primarily because of the prey resources 

 available within it. In addition, the fisheries occurred 

 in the winter and early spring, when sea lions are most 

 likely to consume Pacific cod (Sinclair and Zeppelin, 

 2002). It is not known how or if cod fishery catches 

 in this area affect Steller sea lion foraging success. 

 One objective of the Pacific cod fishery management 

 regulations is to minimize the competitive interactions 

 between locally intense fisheries and Steller sea lions. 

 The suite of groundfish fishery regulations enacted in 

 2001 and 2002 work together to avoid adverse modifica- 

 tion of critical habitat under the ESA. However, based 

 on the observations during 2001 discussed in the pres- 

 ent study, regulations for the eastern Bering Sea Pacific 

 cod fishery should be reviewed to ensure that they meet 

 these management objectives. 



Acknowledgments 



We thank D. DeMaster, G. Duker, B. Fadely, J. Lee, T 

 Loughlin, S. Lowe, S. Moore, and especially M. Sigler for 

 their reviews of early versions of the manuscript. We also 

 give heartfelt thanks to the captains and crews of the 

 FV Northwest Explorer and FV Ocean Harvester, AFSC 

 personnel (E. Acuna, T Buckley, W. Floering, L. Haaga, 

 R. Harrison, E. Jorgensen, G. Lang, D. Nebanzahl, D. 

 Nichol, and K. Smith) who conducted the bottom trawl 

 survey in February-March 2001, and the numerous 

 fishery observers working onboard commercial vessels 

 at that time. 



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