Report of the Progress of Experimental Tuna Fish5.ng Near Woleai 



The skipjack and tuna fisheries, which are the backbone of the fishing 

 industry of the South Seas, have made remarkable progress in recent years, 

 but these devel.:pments have been limited to the Palau, Truk, Ponape, and 

 Saipan areas, these fisheries having been almost entirely neglected in the 

 so-called outlying islands. This is, of course, related to the question of 

 processing the catch, however, when we consider the futi.ire of the fishing 

 industry in the islands vie cannot for a moment overlook the fisheries of 

 these outlying areas. Consequently, in planning the overall promotion of 

 the islands' fisheries we are anticipating the development of these out- 

 lying areas by gradually carrying out experimental skipjack and tuna fishing 

 investigations in them.. The present report is the result of an experimental 

 tuna fishing investigation in the waters adjacent to Woleai. 



The VTriter carried out this investigation aboard the Zuiho Maru during 

 eighteen days, from April 8 to April 25. It was impossible to arrive at 

 any defi-^ite conclusions in such a short period of time, however, the 

 general outline of tlie progress of the investigation is reported here. 



Main P oints of the InvestiKation 



Research vessel Zuiho Maru (183.54 gross tons, Mitsubishi Bikkado 360 HP 



airless injection Diesel engine) 

 Area investigated Woleai to Lamotrek 

 Time of investigation April 3-25, 1936 

 Crew 1 technician in charge and 23 m.en 

 Gear employed /+0 baskets of tuna longlines 

 Construction of one basket 



Trunk-line Nanking hemp, .3 inch diameter, 22- thread, 200 fathoms 



long (8 25-fathom pieces) 

 Dranch lines .24" diameter, 23-thread, 3 lines 15 fathoms long, 3 



lines 7g- fathors long 

 Float lines Same material as branch lines, 2 lines 15 fathoms long 

 Cotton-v/rapped hemp 6 pieces 4. fathoms long 

 Mre leader 6 pieces 1 fathom long 

 Hooks 6 Tosa style, 4.2 inch 



Bait used 



Iwashi taken with a tliroAv-net inside the reef at Palau were salted 

 and used for bait. 



Method of investigation 



Experimental fishing with longlines was done and at the same time 

 oceanographic observations were made on the fishing grounds. An effort 

 was made to provide basic data for commercial operations by studying the 

 distribution of schools, their migrations, the suitability of the fishing 

 gear and methods, and the relationship between oceanographic and fishing 

 conditions. 



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