Time Trends in Abundance and Catchability of Yellowfin Tuna and Their Relationship to the North Atlantic Oscillation Index
نویسنده
چکیده
This paper examines the correlation between biomass and catchability (q) of yellowfin tuna and the NAO index. Biomass estimates are obtained from a biomass dynamic model fitted to catch and cpue for the period 1950-1999. Several assessment scenarios are investigated. Scenarios are defined by the combination of indices used in the biomass dynamic model and the assumptions made about the variance of each index. Catchability trends are estimated by assuming that q varies according to a random walk with known variance.
منابع مشابه
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