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continue to advise the Service in developing the best 

 scientific basis for the regulation of the yellowfin 

 tuna fishery in the period following 1985. However, 

 while the analyses are being carefully prepared, it 

 is important to note the following points: the 

 completed analyses will provide estimates of porpoise 

 populations as they were in 1979 and provide little 

 basis for determining trends since that time; more than 

 fifty percent of the tuna landed in the eastern tropical 

 Pacific is being taken by foreign flag vessels, with 

 the greatest percentage of these coming from Mexico, a 

 country which does not participate in the Inter-American 

 Tropical Tuna Commission observer program. Thus, as was 

 the case last year, there is an inadequate basis for 

 reliably estimating either the numbers or species 

 composition of the porpoise being killed by foreign-flag 

 purse seiners; and even if the kill has been reduced, 

 there continues to be extensive pursuit, encirclement, 

 and capture of porpoise in purse seines, and research 

 aimed at alternative fishing techniques which would 

 obviate the need to use porpoise has been essentially 

 terminated even though the effects of pursuit, encircle- 

 ment, and capture on the animals and on the involved 

 populations remain totally unknown. 



The Commission will continue to seek ways in 1984 

 to resolve the several critical problems outlined above. 



The Pall's Porpoise Issue 



Dall's porpoise ( Phocoenoides dalli ) become entangled 

 and die in the gill nets used by Japanese salmon fishermen 

 in the North Pacific Ocean. As a result of the 

 renegotiation of the International Convention for the 

 High Seas Fisheries of the North Pacific and amendments 

 to the U.S. North Pacific Fisheries Act implementing 

 that Convention, the Japanese are permitted to fish for 

 salmon both within and outside the U.S. 200-mile Exclusive 

 Economic Zone, west of 170° east longitude. This fishing 

 has been subject, among other things, to the provisions 

 of a Memorandum of Understanding between the United States 

 and Japan concerning coordinated research efforts and, 

 beginning 10 June 1981, to compliance with the general 

 permit requirement and other requirements of the Marine 

 Mammal Protection Act with respect to incidental taking 

 of Dall's porpoise and other marine mammals within the 

 200-mile zone. 



