However, little has been done to identify and evaluate 

 the relative costs and benefits of measures that might be 

 taken to avoid or reduce the adverse effects of other 

 interaction problems. This was noted during the Commission's 

 meeting in San Diego, California, in October 1985. Following 

 that meeting, the Commission and the California Department of 

 Fish and Game agreed to cooperatively sponsor a workshop to 

 determine and describe such additional measures as may be 

 necessary to assess, avoid, and reduce impacts on both the 

 involved fisheries and marine mammals. 



The workshop was held at the Fort Mason Center, San 

 Francisco, California, on 26-28 March 1986. It was planned 

 and cooperatively supported by the Commission, the California 

 Department of Fish and Game, the California Sea Grant 

 Program, the National Marine Fisheries Service, and the U.S. 

 Fish and Wildlife Service, and representatives of these 

 groups participated in the workshop. Also participating were 

 representatives of several commercial fisheries, the academic 

 community, and several public interest groups. Workshop 

 participants concluded that several fisheries and marine 

 mammal populations are being affected so severely that 

 measures may be necessary to reduce or mitigate interactions. 

 For example, they concluded that the commercial passenger 

 fishing vessel fishery, the commercial salmon troll fishery, 

 and set gill net fisheries are being affected substantially 

 by California sea lions and other marine mammals that take or 

 damage caught fish. Likewise, they concluded that the 

 incidental take of sea otters, harbor porpoise, harbor seals, 

 and some other marine mammal species may be causing or 

 contributing to population declines. 



Participants recognized that prohibiting the use of gill 

 nets in certain areas is having adverse economic impacts on 

 some fishermen. They therefore recommended that a feasi- 

 bility study and, if appropriate, an engineering/assistance 

 program be carried out to assess the potential utility of 

 converting small gill net vessels to alternative types of 

 gear ( e.g. , Danish seines) to permit resumption of halibut 

 and other finfish fisheries in areas where set net fisheries 

 have been prohibited. The purpose of such conversions to 

 other gear would be to prevent the incidental take of sea 

 otters and other non-target species. Participants also noted 

 that studies should be done to identify factors ( e.g. , the 

 length of time that nets are left in the water) that may be 

 causing or contributing to the incidental take of harbor 

 porpoise, harbor seals, and other marine mammals. 



Noting uncertainties about the effects of certain 

 fisheries on marine mammals, workshop participants concluded 

 that survey, reporting, and observer programs should be 

 continued and, in some cases, expanded to provide more 



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