ABSTRACT 



Catch rate, lure preference, size, weight-length relation, sex and maturity, and food data 

 are presented for the following species of fish: skipjack, little tunny, yellowfin, and dolphin. Where 

 available similar data are reported for frigate mackerel, wahoo, and jack. These fishes were caught 

 by trolling off the northeast coast of Oahu, Hawaii, during the period 1951-55. 



The following inferences were made: The highest availability for all species combined 

 occurred from May to October; no lure preference was found; the presence of one to several size 

 groups was indicated by the weight distributions for these fishes; weight-length relations indicated a 

 sexual difference in dolphin but not for the others; sex ratios showed a preponderance of males for 

 skipjack, equal proportion of both sexes for little tunny and yellowfin, and a preponderance of females 

 for dolphin, although considerable diversity of sex ratios between schools was observed for the latter; 

 gonad examinations revealed mature specimens for all species except yellowfin; food of these troll- 

 caught fishes consisted primarily of fishes, cephalopods, and crustaceans; interspecific competition 

 for food was indicated. 



