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Table 1 . 



Conclusions to be Drawn from the Status of Tuna Stocks 



Concerning the Level of Annual Sustainable Catches 



Relative to Current Effort and Possible 



Management Measures 



Species/Stock/ Fishery 



Catch at or near MSY 



with about optimum 



effort being 



expended under 



current fishery 



management 



Increase in catch likely 

 with an increase in 

 effort 



Increase in catch likely 



with change in 



management provisions 



ATLANTIC OCEAN 



Yellowfin 



Bigeye 

 Skipjack 



Albacore, S. Atlantic 

 Albacore, N, Atlantic 



Catch near MSY 

 especially in eastern 

 Atlantic 



No 



Unknown 



Near MSY with current 

 age structure of catch 



Eastern Atlantic, no; western 

 Atlantic, possibly with in- 

 creased surface effort 



Yes , an annual 1 1 ,000 to 

 80,000 mt increase is likely 



Yes, MSY cannot be calculated 

 but information suggests 

 potential yield higher than 

 current catch especially in 

 western Atlantic. 



Yes, increases of from 6,000 

 to 10,000 mt seems possible 



Small increase in average 

 annual catch likely with 

 increased effort, but 

 recruitment highly variable 

 so probably not prudent to 

 increase effort substantially 



Uncertain 



Some increase to be expected 

 with increase in age of first 

 capture 



Unknown 



No, yield-per-recruit already 

 hinh at 7.7 kq for lonq-line 



Yes, but only with severe 

 restrictions on surface 

 fisheries 



INDIAN OCEAN 



Albacore 

 Bigeye 



Yel lowfin 



Appears fully exploited 

 Unknown 



Longline catch appears 

 to be at maximum 



Lightly exploited, but 

 actual potential unknown 



Yes, especially by surface 

 fisheries 



Skipjack 

 Blue marl in 



Possibly, but there may be 

 errors in total catch estimates 

 which would affect conclusion 



Striped marl in 

 Black marl in 

 Swordf ish 

 Sailfish 



Appears to be ful ly or 

 over-exploited 



Some small increase appears 

 possible 



Increase in catch appears 

 1 ikely 



Yes, potential yield much 

 higher than maximum annual 

 catch thus far 



Unknown 



PACIFIC OCEAN 



Yellowfin , E. Pacific 



Skipjack, E. Pacific 



Yellowfin, W. Pacific 



No, recent catches and 

 effort above MSY and 

 optimum with current 

 aqe structure 



Yes , especial ly for 

 longl ine 



No 



Increases in catch likely 

 with increased effort, 

 especially if smaller 

 fish are caught without 

 affecting recruitment 



Some increase in surface 

 fishery catches possible; 

 total yield may increase 



Yes, increasing the age of first 

 capture would yield substantial 

 improvements in total catch 

 over time 



