in areas as diverse as California, South Africa, Japan, New Zealand, 

 Spain, Peru, and Argentina. The regions have fish specie complexes con- 

 taining anchovy, sardine, mackerel, and hake, all contributing important 

 fisheries which undergo unusual and drastic population crashes and 

 expansions which have great economic effects. Fishery scientists need 

 to understand the mechanisms involved in these changes, which are 

 believed to be due to a combination of physical and biological environ- 

 mental effects on fish survival. 



CZCS data can play an important role in fishery research and fishery 

 management by providing ocean color measurements for use in evaluating 

 environmental effects on the distribution, abundance, and availabiity of 

 fishes for use in the assessment of the status of fish populations. The 

 greatest immediate success in the application of CZCS-type measurements 

 to marine biology is in those cases where there is sufficient under- 

 standing of the biology and oceanic phenomena to identify key ocean- 

 ographic processes (such as ocean fronts and upwelling) that sub- 

 stantially influence the well being, behavior, abundance, and distribu- 

 tion of biota. Ocean color data can also play a significant role in the 

 resolution of subtle scientifically complex problems in marine 

 ecosystems such as the long-term impact of pollution on resource popula- 

 tions. CZCS data are also utilized in fishery aid products for use by 

 commercial and recreational fishermen and other users in the fishing 

 community. 



MAREX investigations for which CZCS measurements may provide essential 

 oceanographic data are: 



a. The determination of year class strength and recruitment, where 

 information is required on marine habitat characteristics, 

 e.g., the distribution of phytoplankton and other prey items 

 critical in the survival of early life stages of fishes. 



b. Migration studies of highly mobile species (such as tuna, 

 billfish, and marine mammals) where migration patterns are 

 linked to ocean features, such as color boundaries which may be 

 monitored over vast areas remotely from space by the CZCS. 



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