DEPARTMENT OF INTERIOR 



Bureau of Commercial Fisheries FY-62 $ 850,000 



FI-63 $1,219,000 

 Surface currents, upwelling, temperature, salinity, oxygen and phosphate 

 content and many other oceanographic parameters greatly influence the 

 biological productivity of the sea. Divergent and convergent currents 

 may create areas of enrichment and they often concentrate the food 

 of important fishes such as herring, mackerel, salmon, sardines and 

 tuna„ Time and rate of seasonal warming of coastal and offshore waters 

 influence distribution and migrations of fishes; for example, the 

 northward movement of Atlantic menhaden in the spring of the year and 

 the appearance of large skipjack tuna in the summer fishery of the 

 Hawaiian Islands can now be predicted on the basis of time of spring 

 warming , The peak spawning time of Pacific sardines is known to vary 

 from one year to the next by as much as two months in response to 

 oceanic temperature changes no greater than 1°C. Unfavorable currents 

 in some years may carry haddock larvae away from the usual nursery areas 

 and a large part of the young are lost. Fishery scientists believe that 

 the pattern of ocean currents at the time of spawning is an important 

 factor in the survival of year broods in many important fisheries. 



Oceanography of the central and eastern Pacific is currently being 

 studied from several Bureau laboratories located in Hawaii, Alaska 

 and along the Pacific coast of the United States, Some principal 

 contributions are: (l) monitoring the seasonal north-south drift of the 

 California current extension from stations near Hawaii where trends in 

 sea surface temperatures, salinity and sea levels are determined; (2) 

 definition of physical and chemical features of Pacific subarctic waters 

 as part of an extensive program to explain factors controlling high-seas 

 distribution of salmon; (3) detailed analysis of North Pacific sea- 

 surface temperature data by months from 1935 to the present along with 

 related meteorological processes which may cause variations in water 

 transport, heat gain or loss and sea levels; {h) cooperative studies 

 with California agencies on the California current system and physical 

 oceanographic features of the eastern, subtropical and tropical Pacific. 

 Prevailing sea-surface temperatures for the North Pacific east of 180° 

 longitude are charted and published monthly for use in fishing and 

 research operations. 



Much of the Bureau's research in the Gulf of Mexico and along the 

 Atlantic coast is directed towards coastal and inshore oceanography to 

 describe the environment and to determine productivity of coastal 

 resources. Circulation and net current flow through bays and inland 

 passages are under study as a significant contribution to research on 

 shrimp, oysters and menhaden . Through a small contract with Woods Hole 

 Oceanographic Institution, temperature and salinity conditions are 

 monitored routinely at numerous Atlantic coastal stations and from 

 lightships and Texas towers. Circulation patterns over the New England 

 offshore banks and in the Gulf of Maine are studied by use of drift 



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