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albacore stock to changes in age at-first-capture under a variety of stock 

 recruitment hypotheses. Under constant recruitment, MSY was judged to be 

 about 38,000 mt at an age-of- first-capture of 4 years, but MSY at 3-year or 

 5-year minimum age limits was only slightly less. Under more conservative 

 stock-recruitment hypotheses, lower MSY's were computed and were achieved 

 at progressively higher ages-at- first-capture. The results of the 

 simulation analysis are considered to be preliminary. 



1 1 I.e. Current Evaluation of Stocks and the Fishery 



The South Pacific albacore stock is considered to be in a healthy 

 condition. Catch-per-unit-effort in the longline fishery has been reduced 

 considerably to perhaps 20% of its initial level, but unless recruitment is 

 strongly dependent on size of spawning stock, such a reduction can be 

 sustained. There is no indication of recruitment failure. Following its 

 peak in 1973 the nominal effort has been reduced. Catch rates have 

 increased; therefore, average annual catch has increased in spite of lower 

 effort. Further reduction in longlining effort should be beneficial. 



Expansion of surface fisheries may be feasible. Indeed, Japanese 

 baitboats are known to be considering exploratory albacore fishing 

 expeditions in the region of the subtropical convergence east of New 

 Zealand (Shiohama 1979). 



IV. STATUS OF CURRENT RESEARCH NEEDS AND EFFORTS 

 IV. A. Major Research Problems 



Evaluation of potentials for expanding surface fisheries on South 

 Pacific albacore is an important area for research. This would require 1) 

 theoretical studies of stock productivity using age- structured simulation 

 models, 2) possible tagging of 2- and 3-year old albacore available to 

 development of the surface gear, 3) evaluation of recapture rates in the 

 longline fishery, and 4) methodology to predict surface fishery potentials 

 using the wealth of observations on the subsurface longline operations. 



IV. B. Current Research Efforts 



Current work on South Pacific albacore by the SWFC includes: 



1) Improving the data base for South Pacific albacore through a 

 general upgrading of the American Samoa catch-per-unit-effort and 

 landings statistics. 



