United States Department of the Interior 

 Oscar Lo Chapman, Secretary- 

 Fish and Wildlife Service 

 Albert M„ Dayj Director 



Special Scientific Report - Fisheries 

 No. 51 



JAPANESE SKIPJACK STUDIES 

 Translated from the Japanese language by 

 Wo Go Van Campen 

 Pacific Oceanic Fishery Investigations 



CONTENTS 



lo A note on the fisheries condition of "katuo" as a function 

 of several cceano graphic factors^ By Michitaka Uda l/. . . . 



Page 



2„ The time and duration of angling and the catch of "katsuo", 



Euthynnus vagans (Lesson) ^ By Wichitaka Uda 2/ .,„,.....=.., 12 



3. The body- temperature and the bodily features of "katuo" 



and " sanma" j By Michitaka Uda 2,/ . » . » o <> . . » <. o » » . » . <, , « o » . . . . . , 18 



4,. On the weight composition of skipjack schools in the 

 northeastern sea area, Bf Gorozo Okamoto (Central 



1/ From the Bulletin of the Japanese Society of Scientific Fisheries, 

 Volo9, No„4s, pPoU5-U8, October,, 19A0c, 



2/ From the Bulletin of the Japanese Society of Scientific Fisheries, 

 Vol„9, No„3, ppol03-106<. September, 19-iOo 



2/ From the Bulletin of the Japanese Society of Scientific Fisheries, 

 Vol.9, Noo6, pp„231-236„ March, 19Uo 



4/ From Bulletin of the Japanese Society of Scientific Fisheries, 



Vol, 9, NOo3, ppol00-102„ September 19^0o 



