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3) Exploitation rates need to be developed. 



4) Management models such as yield-per-recruit and surplus 

 production need development. 



5) Factors relating to management, such as time-area patterns 

 of occurrence, need evaluation. 



IV.C.l. Suggested Approach and Methods 



In addition to current work being done at SWFC, the 

 following projects might be considered: 



1) Exploitation rates could be developed for the 

 eastern Pacific utilizing information obtained from tagging, cohort 

 analysis, mortality, and emigration analyses yet to be done. 



2) Aerial spotter information might be used to develop 

 indices of abundance. 



IV. D. Status of SWFC Data Base 



The data base, which has been established this year via the NMFS- 

 CF&G project, consists of eastern Pacific tuna logbook data, 1957 to 1970, 

 1974; length- frequency data, 1923 to 1925, 1951 to 1966; length-weight-age 

 data, 1963 to 1971; length-weight data, 1960 to 1965, 1971 to 1974; monthly 

 California landings, 1926 to 1976; tag return data, 1953 to 1969; and a 

 vessel list, 1957 to 1978. 



The data base for the western Pacific is the Japanese longline 

 information, 1962 to 1980; the Japanese baitboat information, 1970 to 1976; 

 and the Taiwanese deep sea longline information, 1967 to 1975. 



