TOiatever the causes may have beeiij the fact remains that the 

 change over from single vessel to mother ship -type operation was a 

 great stride forward in the tuna longline fisheryo And it may 

 prove to have been an essential stage in the path of development of 

 this fisheryo 



So consideredj the tuna longline fishery, compared to the 

 bottom fisheries, can be thought to be in its youth or in a pri- 

 mitive stage of developmento If this view is correctj it must mean, 

 on the other hand, that the tuna longline fishery has many unexploited 

 fields which will be greatly developed in the futureo 



If we look at conditions since the war, we see that the tuna 

 longline fishery, through the establishment of a number of large 

 and small so-called "new" fishing companies^, and especially through 

 the advance into this fishery of the Nichiro Fishing Company, which 

 was prominent for many years in the fisheries in northern waters, 

 has become quite suddenly the bright star of the Japanese fishing 

 industryo This situation does not, however, necessarily represent 

 an essential stage in the development of this fishery^ It is, 

 rather^ in large measure something made unavoidable by the res- 

 trictions of various kinds under which Japanese fisheries have 

 been placed during the Occupation, and it also partakes to a large 

 extent of the nature of an emergency measure taken in the face of 

 the great general overturn in the Japanese economy„ Accordingly, 

 one cannot, unfortunately, deny the impression that at bottom it 

 still retains an element of instability„ 



As to the second point, the differences in fishing gear and 

 methods 5, they may, after all, be ascribed to the marked differences 

 of environment and habits of the fishes soughto 



In the open sea, where the depth of the water attains to 

 several thousand meters, there is absolutely no place for the 

 establishment of a trawl fishery. Seines and gill nets, too, 

 require many conditions for their use, and they cannot be operated 

 at just any time or any placeo Therefore under present conditions, 

 except in sea areas which offer certain particular characteristics, 

 the establishment of net fisheries for tuna cannot be considered„ 

 This is, however, a view based on present conditions, and in case 

 in the future a method is devised for causing fish to concentrate 

 within a small area by means of special kinds of light rays, sound 

 waves, or the like, the establishment of a net fishery will become 

 by no means impossibleo 



Stated in an extremely general sense, net fisheries are a 

 great deal more efficient than hook and line fisheries^ The 

 obviousness of this is witnessed by the common saying "Net — rich 

 mani line -- beggar," For example, according to prewar statistics, 

 the catch per ton of fuel oil consumed was 5-6 tons in the trawl 

 fishery and around 2-3 tons in the tuna longline fishery„ This 

 high catching efficiency, considered only from the point of view 



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