112 



FISHERY BULLETIN OF THE FISH AND WILDLIFE SERVICE 



60 



60 



70 



140 



ISO 



160 



80 90 too 110 120 130 



TOTAL LENGTH IN CENTIMETERS 



FroTTBE I. — Length frequencies (if yellowlin tuna measured aboard the ujothership Temjo Maru No. 2. June-August 1950. 



extent by the Japanese and is highly effective for 

 fishing subsurface levels for tunas and otlier com- 

 mercially valuable fishes otherwise unavailable to 

 fishermen. Although variations in the construc- 

 tion of gear and minor differences in operating 

 technique existed among the manj' fishing vessels 

 of the expedition, the louglines were built and 

 handled essentially in the same manner by all ves- 

 sel'; A good description of Japanese longline 



gear and fishing methods is given by Shapiro 

 ^(1950). 



The principal species of fish landed was the yel- 

 lowlin tuna {NeotJiunnus macropterus) w^hich 

 comprised more than 50 percent of the total catch 

 bj^ v\eight and ninnber. Yellowfin tuna, because 

 of their export value, were delivei'ed to the mother- 

 ship as whole fish for freezing, whereas other 

 species were usually gutted at sea. Those yellow- 



