CHAPTER HI — MDRLD PRODUCTION 



Abstract 



tunar. comprise a renewable biological resource not limited to co^ftinental 

 shelves and unknown in potential production, 



Although much work has been done to discover tuna grounds and to develop 

 methods of capture and use, the elementary biological features of the tunas are 

 only beginning to be understood. 



occurrence of tuna in commercial quantities has been correlated with cur- 

 rent patterns in warmer seas„ 



ufwellings of deep water provide nutrients favorable to the growth of 

 plai*kton necessary as food for tunas or other animals eaten by tunas. 



The PRINCIPAL AREAS NOW BEING FISHED ARE THE PACIFIC OCEAN NEAR THE COASTS 



OF Asia and North and South America, and the Atlantic and Mediterranean waters 



OFF southern and WESTERN EUROPE. 



In SOME PARTS OF THE WORLD (PERU, ANGOLA, THE EAST COAST OF AUSTRALIA, THE 



NORWEGIAN Sea, and Northeast United States) development of tuna fisheries has 

 begun, and substantial product loig has been achieved in some instances. 



Unexplored areas favorable for the existence of commercial quantities of 

 tuna appear to be in ( i ) the equatorial circulation of the atlantic and indian 

 Oceans, (2) the northeastern Pacific gyral, (3) the current flowing northward off 

 WESTERN Australia, and (4) the Gulf Stream where it meets the coastal wati^rs alons 

 North America. 



It is thought that landings can be maintained in heavily exploited areas 



AND increased ON A WORLD-WIDE BASIS. 



The United States catch could be greatly increaoEd qy adoptins methods for 



TAKING subsurface STOCKS NOT NOW EXPLOITED, AND BY FISHING NEW AREAS IN THE 



mid=Pacific„ 



In pre=World War 1 1 yei^s the world's tuna industry was confined mainly to 

 the seas arou^d japan, the ik.ed i terranean and adjacent atlantic ocean, and the 

 Pacific Ocean off Central America. 



Japan, the United States, and Turkey together caught 88 percent of the 



entire PRODUCT] on. 



Since the war, the increased demand for canned tuna in the United States A^D 

 Italy has stimulated world interest in the tuna fisheries. 



Operations have been expanded and new industries have been developed, prin- 

 cipally OFF THE SOUTHERN PACIFIC COAST OF THE AMERICAS AND OFF WESTERN AND NORTHERN 



Europe. 



The world's catch increased from 825 million pounds in i939 to over i bil- 

 lion POUNDS IN l95l. 



Further expansion is expected in presently productive areas and other warm 



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