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I.B. Trends in Catch and EFfort 



I.B.I. Eastern Atlantic Fishery 



Catches of yellowfin tuna for the eastern Atlantic 

 longline fishery peaked in 1973 at 25,000 mt, then decreased gradually to 

 an estimated 5,000 mt in 1980 (Figure 3a). Surface fishery catches, in 

 contrast, increased from 36,000 mt in 1966 to a record high of 110,000 mt 

 in 1979. Estimated surface catches in 1980 decreased to 95,000 mt 

 (preliminary estimates). 



Estimated fishing effort for the eastern Atlantic 

 longline fishery from 1967 to 1977 is shown in Figure 4a. Effort increased 

 to a high of 91 million hooks in 1973, then decreased to 43 million hooks 

 in 1977. Estimated fishing effort for the eastern Atlantic surface fishery 

 from 1967 to 1979 was estimated by dividing the total eastern Atlantic 

 surface yellowfin catch by catch-per-unit-effort for the FISM fleet, the 

 major harvester (Figure 4b). Surface fishery effort increased from 8,000 

 standard days absence (SDA) in 1967 to 57,000 SDA in 1979. 



I.B.2. Western Atlantic Fishery 



Catches from the western Atlantic longline fishery 

 have fluctuated between 7,000 mt and 15,000 mt during the period 1966 to 

 1980 (Figure 3b). Surface fishery catches have fluctuated from a high of 

 4,700 mt in 1978 to a low of 600 mt in 1976. 



Estimated effort for the western Atlantic longline 

 fishery increased from 25 million hooks in 1967 to 65 million hooks in 

 1973, then fluctuated between 46 and 58 million hooks from 1974 to 1977 

 (Figure 5). No estimates of surface effort are available for the western 

 Atlantic. 



I.e. Value of Catch 



The 1979 U.S. average ex-vessel price for yellowfin tuna was 

 $893/mt for fish less than 3.2 kg and $l,047/mt for fish greater than 3.2 

 kg. Based on an average price of $970/mt, the value of the 1979 eastern 

 Atlantic longline and surface yellowfin tuna catch (130,00 mt) was 

 approximately $126 million. The western Atlantic catch (11,100 mt) was 

 worth approximately $11 million. 



