ABSTRACT 



Bigeye tuna (Parathunnus sibi) weight data from the Honolulu 

 market for the period 1947-54, length data collected aboard Japanese 

 tuna motherships in the equatorial western Pacific in 1951, and pub- 

 lished length frequency distributions from the Japanese longline fishery 

 in the northwest Pacific were compared and studied for evidence of 

 growth and of local differences in the size composition of the population. 

 In the data from both the e:|uatorial western Pacific and Hawaiian 

 waters the modes of the male size distributions were found to be about 

 14 cm. or 30 pounds larger than the corresponding female modes. 

 Monthly weight frequencies of Hawaiian bigeye showed a consistent 

 progression of modes, yielding a provisional growth curve that indi- 

 cates that these fish may gain as much as 50 pounds in 1 year and may 

 live about 6 or 7 years, Relatedness of the bigeye in Hawaiian waters 

 and in the Japanese North Pacific fishery is suggested by the approxi- 

 mately similar growth rates and by the presence of a complementary 

 2-year cycle of dominant size groups in the catches of both areas. 

 Data from equatorial waters showed no progression of the modes with 

 time. 



