of the Gulf Stream and the coastal waters of our north Atlantic shores 

 may eventually prove to be akin to the impingement on adjacent waters 

 of the Kuroshio of Japan in supporting tuna, though it seems that the 

 magnitude of the stock must be modest to have escaped notice so faro 



Not only do there appear to be unexplored opportunities for tuna 

 production in the geographic sense , but also in the sense of neglect- 

 ed specieSj life history phases^, and aggregational phases. Thescjtoo, 

 involve the geography of distribution^, but knowledge of the habits of 

 the fish in relation to catching techniques in some instances and 

 market acceptance in others are the principal problems. This field of 

 consideration ramifies so extensively that it can only be touched upon 

 here. On the west coast of North and Central America four species com- 

 prise practically the entire United States catch: yellowfin, skipjack, 

 albacore, and bluefino Yet there are two others in the area which are 

 common and if commercially sought might yield surprisingly large catches. 

 They are the "little tunny" (Euthynnus lineata) and the big -eyed tuna 

 ^arathunnus sibj) . The fonner is generally of smaller size than desir- 

 able and very dark fleshed; the latter is larger sized than desirable 

 and similarly dark fleshed but not as extremely so. These could be 

 drawn upon eventually if a very great enlargement in demand should far 

 outstrip the supply of the presently more desirable species. 



The three species which form the mainstay of present supply, 

 yellowfin, skipjack, and albacore, are fished during only that segment 

 of their life histories which might be termed late youth and early 

 adulthoodo The main bulk of the adults almost completely eludes cap- 

 ture in the American fishery. In part, this miay be attributed to the 

 fishing methods which are effective only fcr surface swimming fisho In 

 part it is due to our ignorance as to where the major part of their 

 adult life is spent. With increased knowledge of the age-connected 

 habits of these fishes and employment of appropriate gear, new gains 

 in catch might be drawn from the older components of the stocks al- 

 ready fished in their younger phases. 



In summary, biological considerations suggest that the outlook 

 is favorable for sustaining the present tuna yield and perhaps increas- 

 ing it manifold on a world-wide basis. The avenues of expansion for 

 our present largely developed fishery on the West Coast probably are 

 not most promising along continued growth in directions pursued in the 

 past, but in tapping new stocks » Geographically the most available 

 would be the eastern portion of the proved yellowfin stocks of the 

 trans-Pacific equatorial zone and the hypothecated albacore stock of 



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