PRELIMINARY ANALYSIS OF THE FORK LENGTH-WEIGHT RELATIONSHIPS AND ROUND WEIGHT-DRESSED WEIGHT RELATIONSHIPS OF BIGEYE TUNA (THUNNUS OBESUS) SAMPLED FROM CHINA TUNA LONGLINING FLEET IN CENTRAL ATLANTIC OCEAN

SUMMARY Based on the fork length(FL), dressed weight (DW) and round weight (RW) data of bigeye tuna(mixed, male and female) sampled in random from three China larger scale tuna longliners operating in the Central Atlantic Ocean high sea area and targeting bigeye tuna from 16 th Jun. 2001 to 27 th Oct. 2001, this paper analyzed the mixed, male and female bigeye tuna’s FL-DW , FL-RW relationships by the power regression method, RW-DW relationships by the linear regression method. The results indicated (1) The mixed, male and female bigeye tuna’s relationship between FL and DW was DW=1.5286×10 -5 FL 3.0192 , DWM=1.6102×10 -5 FL 3.0098 ,DWF=1.4998×10 -5 FL 3.0205 ,respectively. (2) The mixed, male and female bigeye tuna’s relationship between FL and RW was RW=2.6472×10 -5 FL 2.9400 , RWM=2.8164×10 -5 FL 2.9275 , RWF=2.2590×10 -5 FL 2.9724 , respectively. If the FL was the same, the mixed bigeye tuna’s RW converted in this paper’s formula was a little lighter than it converted in Parks’s formula concluded at 1981. (3) The mixed, male and female bigeye tuna’s relationship between RW and DW was RW=1.1623DW， RWM=1.1546DWM ,RWF=1.1840DWF , respectively. The RW convert factor in this paper was a little bigger than the ICCAT. RESUME