corkline at the surface and a leadline at the bottom. The nets 

 are set at the surface at night and retrieved at daybreak. It is 

 estimated that the squid driftnet fleets alone set approximately 

 32,000 kilometers of net each night during the height of the 

 fishing season which lasts from May to December. 



Evaluation of the impact of driftnet fisheries on marine 

 mammals and other bycatch species is hindered by lack of reliable 

 information on fishing effort, incidental catch by species, 

 fishing area, and seasonal movements of fishing vessels. 

 Although there are fairly reliable estimates of the numbers of 

 marine mammals, particularly Dall's porpoise taken in the 

 Japanese salmon mothership driftnet fishery, there are no good 

 estimates of the numbers of marine mammals caught incidentally in 

 any of the high seas squid driftnet fisheries or the large-mesh 

 billfish and tuna driftnet fisheries. The species known to be 

 taken in driftnet fisheries in addition to Dall's porpoise 

 include harbor porpoise, northern right whale dolphins, Pacific 

 whitesided dolphins, common dolphins, striped dolphins, northern 

 fur seals, and Steller sea lions. 



Development of Cooperative Marine Mammal Observer Programs 



The International North Pacific Fisheries Commission serves 

 as a forum for coordinating the collection, exchange, and 

 analysis of scientific data regarding anadromous fish in the 

 North Pacific Ocean. Because marine mammals were taken inciden- 

 tally within the U.S. Exclusive Economic Zone in the high seas 

 salmon driftnet fishery operating pursuant to the Annex of the 

 International North Pacific Fisheries Convention, the Federation 

 of Japan Salmon Fisheries Cooperative Association (the 

 Federation) was required to obtain a general permit to take 

 marine mammals incidental to their commercial fishing activities 

 (see the preceding discussion) . The general permit, originally 

 issued to the Federation for three years beginning in 1981, was 

 legislatively extended until 9 June 1987. On 22 May 1987, the 

 National Marine Fisheries Service issued a new, three-year 

 general permit to the Federation, authorizing the incidental take 

 of Dall's porpoise. 



Among the conditions of the 1987-1989 general permit, the 

 Japanese were required to accept the placement of observers 

 aboard all motherships and a specified number of catcherboats 

 operating in the high seas salmon fishery. The permit also 

 required Japan to accept the placement of U.S. marine mammal 

 observers on its land-based salmon fleet and its high seas squid 

 gillnet fleet, to the extent that such observers could be 

 provided. Although a memorandum of understanding to implement 

 the other permit conditions was signed by the United States and 

 Japan on 8 June 1987, it did not include a provision for the 

 placement of observers in the high seas squid driftnet fleet. 



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