or marine mammals. They identified the types of research and 

 monitoring programs necessary to determine the nature, magni- 

 tude, and effects of the interactions. 



Although substantial effort has been devoted to determining 

 the nature, magnitude, and effects of marine mammal/ fishery 

 interactions, relatively little has been done to identify and 

 evaluate the relative cost and benefits of measures that 

 possibly could be taken to avoid or reduce the adverse effects 

 of interactions. This fact 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 the adverse effects of 

 interactions between marine mammals and fisheries in California. 

 The workshop, held on 26-28 March 1986, was planned and sup- 

 ported cooperatively by the Commission, the California Depart- 

 ment of Fish and Game, the California Sea Grant Program, the 

 National Marine Fisheries Service, and the Fish and Wildlife 

 Service. Participants included representatives of these 

 agencies, commercial fisheries, the academic community, and 

 public interest groups. Workshop participants concluded that 

 several fisheries and marine mammal populations in California 

 were being affected so severely that measures may be necessary 

 to reduce or mitigate interactions. 



Workshop participants noted that steps taken by the 

 California Department of Fish and Game and the California 

 State Legislature to prohibit the use of drift nets and set 

 nets at certain times and in certain areas to prevent or 

 reduce the incidental take of sea birds and marine mammals 

 were having an adverse economic impact on some fishermen. They 

 recommended that a feasibility 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 and pair trawls) 

 to permit resumption of halibut and other fisheries in areas 

 where use of set nets have been prohibited to protect birds, 

 sea otters, harbor porpoise, and gray whales. 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 in 

 California and elsewhere. 



Because of uncertainties concerning the effects of some 

 fisheries on marine mammals, workshop participants concluded 

 that survey, reporting, and observer programs should be con- 

 tinued and, in some cases, expanded to provide more reliable 

 information on the species, numbers, ages, sex, and reproductive 

 condition of marine mammals being taken, both deliberately 



167 



