off the U.S. west coast from Washington to California, and 

 off New England. The Commission, concerned that these studies 

 might not be providing either comparable data or the types 

 and quality of data needed for decision-making, convened a 

 second workshop in October 1981 to review and determine what 

 steps should be taken to improve and coordinate ongoing and 

 planned studies. 



Participants in the 1981 workshop concluded that: (1) it 

 is not possible to make broad generalizations about marine 

 mammal/fishery interactions in different areas and each situ- 

 ation must therefore be considered individually; (2) because 

 of the potentially complex nature of indirect (trophic) inter- 

 actions among marine mammals, fisheries, and fish and shellfish 

 resources, there is a substantial risk of making bad management 

 decisions; (3) to minimize this risk, marine mammals and 

 fisheries should be managed cooperatively in areas where they 

 may be competing for, or otherwise affecting, the same fish 

 or shellfish stocks; (4) because funding is limited and direct 

 interactions are less complex and therefore easier to assess 

 and deal with, high priority initially should be afforded to 

 research on direct rather than indirect interactions; (5) 

 ongoing efforts to determine and document the nature and extent 

 of impacts on both the involved fisheries and marine mammal 

 populations should be expanded to identify and evaluate the 

 relative cost and benefits of possible mitigation measures; 

 and (6) when remedial measures are determined to be necessary, 

 non-lethal measures should be considered before lethal measures. 



These workshop findings have guided subsequent Commission 

 efforts as described below. 



Interactions in California Coastal Waters 



Investigations to determine the nature and extent of 

 marine mammal/ fishery interactions in California coastal waters 

 have been underway since 1979 as a cooperative project of the 

 National Marine Fisheries Service and the California Department 

 of Fish and Game. As noted in previous Annual Reports, these 

 investigations indicate that marine mammals are affecting a 

 number of California fisheries including the commercial salmon 

 troll fishery, the commercial passenger fishing vessel fishery, 

 the Pacific herring seine fishery, the market squid dip net 

 fishery, the drift net fishery for sharks, and set net fisheries 

 for halibut, croaker, and rockfish. They also indicate that 

 substantial numbers of sea otters, harbor porpoise, sea lions, 

 harbor seals, and other non-target species are being caught 

 and killed, particularly in the drift net and set net fisheries. 



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