FISHERY BULLETIN: VOL. 80, NO. 2 



tude and direction of potential bias in these two 

 estimators. 



In spite of the present uncertainties in the 

 accuracy of both the spawning escapement and 

 the acoustic-trawl estimates, the results are well 

 suited to the current management plan of the 

 fishery. The objective of present management 

 procedures is to maintain the population at 

 recent historical levels through a combination of 

 a biologically reasonable exploitation rate and a 

 minimum escapement level. The accuracy of the 

 acoustic techniques probably already exceeds 

 our understanding of optimal exploitation rates. 

 Thus, while improvements are conceivable and 

 may be dictated by future developments in the 

 fishery, the present procedures provide a sound 

 interim approach with timeliness which has 

 been rarely achieved in fishery management. 



ACKNOWLEDGMENTS 



Collection and analysis of catch records and 

 acoustic, trawl, and spawning ground data was 

 conducted and financed primarily by the Marine 

 Fish Program of the Washington Department of 

 Fisheries. Supplemental funds and personnel 

 have been provided by the Fisheries Assistance 

 Office of the U.S. Fish and Wildlife Service and 

 by the Lummi, Swinomish, Nooksack, and 

 Suquamish Indian Tribes which participate in 

 the fishery. 



This analysis was partially supported by the 

 Washington Sea Grant Program under the 

 National Oceanic and Atmospheric Administra- 

 tion, U.S. Department of Commerce. 



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