line and pot fishermen to take killer whales only by non-lethal 

 means. Recognizing that funding constraints limited the Ser- 

 vice's ability to undertake a major research program, the Com- 

 mission recommended that the Service: (1) consult bio-acous- 

 ticians, killer whale and other cetacean biologists, behavioral 

 experts, fishery gear experts, and the affected fishermen to 

 identify possible mitigation measures that would be effective, 

 but not kill or injure the affected whales; (2) based on these 

 consultations, design and seek the assistance of the affected 

 fishermen in carrying out field trials to assess the likely 

 cost and benefits of the possible solutions judged most pro- 

 mising; and (3) continue to survey fishermen, researchers, 

 and others working in Prince William Sound and other areas of 

 killer whale/fisheries interactions to better assess and monitor 

 levels of fish loss and killer whale mortality and injury. 

 The Service subsequently modified the general permit to allow 

 fishermen to use only non-lethal means to keep killer whales 

 from taking caught fish. It also continued survey efforts as 

 recommended by the Commission, but was unable to initiate 

 efforts to identify and assess possible mitigation measures. 



The State of Alaska made funds available in 1986 to evalu- 

 ate possible mitigation measures. As noted in the Commission's 

 previous Annual Report, the extension agent of the Alaska Sea 

 Grant Marine Advisory Program in Cordova, Alaska, had a tele- 

 phone conference on 19 June 1986 with representatives of the 

 Commission, the National Marine Fisheries Service, and several 

 other organizations to seek advice on how best to use the 

 State funds. During this telephone conference, Commission 

 representatives pointed out that: there are no obvious solu- 

 tions to the problem other than prohibiting long-line fisheries 

 at times and in places that killer whales are present; trial 

 and error experimentation with explosives or other possible 

 deterrents could result in habituation and positive rather 

 than negative reinforcement, making the problem more difficult 

 to overcome; better understanding of acoustic or other cues 

 attracting killer whales to vessels retrieving long-line gear 

 might suggest ways for avoiding or reducing interactions; and 

 a workshop involving the affected fishermen, cetacean biolo- 

 gists, acousticians, and other relevant experts likely would 

 be the most effective way to determine how best to identify 

 and evaluate possible ways to prevent or reduce interactions. 



During the summer and fall of 1986, researchers from the 

 Alaska Sea Grant Program conducted additional studies to assess 

 and monitor the killer whales affecting and being affected by 

 the sablefish fishery in Prince William Sound and to determine 

 whether entangling caught fish or other non-injurious means 

 might be useful for preventing or reducing killer whale depre- 

 dation of caught sablefish. In addition, the National Marine 

 Fisheries Service extracted and analyzed data from existing 

 observer reports and asked observers placed aboard Japanese 



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