ILLUSTRATIONS 



FIGURE Page 



Frontispiece: The 46-foot vessel, Salpa, used in catching tuna and other pelagic fishes. The 

 trolling poles are lowered when fishing. 



1. Fishing area off the northeast coast of Oahu, Territory of Hawaii 2 



2. Average annual catch per hour's trolling for all species combined and for the four most 



abundant species in the catch over the period 1951 to 1955. 3 



3. Average monthly catch per hour's trolling for all species combined and for the four most 



abundant species in the catch over the period 1951 to 1955. 5 



4. The three main types of lures used in trolling. 6 



5. Weight composition of skipjack by months for the combined data of 1951 to 1955 9 



6. Weight composition of little tunny by months for the combined data of 1951 to 1955. ... 9 



7. Weight composition of yellowfin by months for the combined data of 1951 to 1955 11 



8. Weight composition of dolphin by months for the combined data of 1951 to 1955. . . . .11 



9. Weight-length relation of dolphin 15 



10. Relative importance of fishes, cephalopods, and crustaceans in the diets of skipjack, little 



tunny, yellowfin, and dolphin 2 1 



