VERIFICATION OF BIGEYE TUNA LENGTH AND CATCH DATA CONSISTENCY FOR TAIWANESE LONGLINE FISHERY IN THE ATLANTIC

SUMMARY The fishing types are investigated in terms of number of hooks between floats for Taiwanese longline fleets in the Atlantic, and annual mean weight that obtained from different methods is estimated to verify the length frequency and catch data. The results obtained shows that 10 or more hooks between floats could be classified as deep longline fishing type and target tropical species; and that 9 or less hooks between floats as regular longline fishing type and target albacore as usual. Annual mean weight estimated from length frequency sampled is much more coincident to the total catch reported in TASK I, in contrast, mean weight estimated from TASK II reported previously shows discrepancies and fluctuation in comparison with those from length frequency. This verify that the length frequency sample and catch estimation from those length frequency sound accurate and could be used in the stock assessment.