NATURAL asscyncE: szciic^ 



REPORT NUMBER lOU 

 9 March 19US 



, THE JAPANESE 1UNA FISHERIES 



TABLE OF CCSJTENTS 



Page 

 Summary 5 



Introduction. 



Classification IZ 



1. General 12 



Skipjack 15 



1. General 15 



2. Diagnostic Characteristics 15 



5. Distribution and Migration 15 



L. Oceanographic Data 17 



5;. Habits 1«? 



6, Econodiics , 1^ 



Black (Or Blaefin) Tuna IS 



1. General 18 



?. Diagnostic Charact»»rlstlc8 19 



3. Distribution and Migration 19 



U, Oceanographic Data 22 



5. Recent Oanges in Pishing Grounds 85 



6. Habits , 23 



7. Econixiics 2U 



Albaccre. 2U 



1. Genftral 2U 



2. Diagnostic Characteristics 2l| 



5. Distribution and Migration 2h 



, h- Oceanographic Data 28 



5. Habits. , , 28 



6. Gconcmlcs 28 



YelloYffin Tuna 2g 



1. General 23 



2. Diagnostic Characteristics. . ?9 



5. Distribution and Migration 29 



U. Oceanographic Data 52 



5. Habits 52 



6. Econoirics 52 



Tuna Fishing Vessels 52 



Tuna Fishing Gear 5ll 



1. General 3U 



2. Tuna Set Net 57 



3. Drift Net 37 



U. circling Net UO 



5. Spears. . ^ . , IjO 



6. Trolling Jig UO 



7. Long Line UO 



8. Pole and Line IfU 



P-6307 



