Plan for the development of the tuna fishery in the South Sea islands (From Kaiyo 

 GyogyS, Volume 5, 1940): 



The tunas are distributed over an extremely wide range in the South; the stability 

 of their fishing grounds has been in general established by various investigations undertaken in 

 the past. However, because of the distance of these grounds from Japan and the fact that they 

 lie within the tropics, the only exploitation of the area has been the fishing done in the South 

 China Sea, the Sulu Sea, and the Celebes Sea by boats based in Formosa. Boats from Japan have 

 generally operated in the Pacific Ocean grounds in the vicinity of 180 longitude. 



With the recent strengthening of the controls on fuel oil and other materials essential 

 to the fishery, the vessels operating in the North Pacific have nnade a 90 turn auid have sought 

 fishing grounds in the southern Caroline Islemds. Good results were obtained and an increasing 

 number of vessels have continued to fish in this area. In 1938 a total of 39 large vessels nnade 

 145 cruises to take a catch valued at 1, 560, 831 yen. At the same tinne the researches of the 

 South Seas Governnnent-Oeneral Fisheries Experiment Station and surveys carried on by the 

 Nanko Fisheries Company have shown the value of these grounds and the South Sea island 

 grounds have quite suddenly become the center of the tuna fishery. 



However, the present type of single vessel operation from Japan still has sonne dis- 

 advantages. As we fortunately have suitable advance bases in the area, it should be profitable 

 to call together the large fishing vessels now operating singly, form them into an organized 

 fleet, and assign to that fleet refrigerated cargo vessels which would carry the catch to Japan. 

 (The rest of the plan is onnitted. ) 



It was planned to use as motherships diesel-powered vessels of 500 tons, each 

 mothership to transport the catch amd supply necessary materials for six fishing vessels. It 

 is imagined that the connparison between the inconne and expenditure of this type of operation 

 and single vessel operation would be as shown in the following table. 



Table 9. --Comparative income and expend- 

 itures of single vessel and 

 mothership-type operations 

 (plan of the Kaiyo Gyogyo Kyokai) 



Note: (1) Catch per fishing boat per trip 82, 700 

 pounds. 



(2) Calculated at the price of 1 yen per kan 



(8. 27 pounds). 



(3) The foregoing table is for 6 fleets, a total 



of 36 fishing boats. 



(4) From Kaiyo Gyogyo, Volume 5, 1940. 



As was made clear above this plan is not for a pure mothership-type fishery, as it 

 envisages the establishment of an advance base, and the reduction of the overhead expenses of 

 single vessel operations by having the so-called mothership transport the catch and the opera- 

 ting materials for a number of fishing boats. In actuality this scheme never got beyond the 

 planning stage and was never put into operation. 



18 



