UW Aquatic & Fishery Sciences Quantitative Seminar

Jim Ianelli

Affiliate Professor, UW & REFM Division, NMFS/NOAA Alaska Fisheries Science Center

A sampling of analytical methods used for fisheries management

Abstract

Analytical methods used for fishery management purposes vary broadly and continue to evolve. Spatial characteristics of stocks inform how survey data should be treated and also management considerations (e.g., time-area specific TACs). In another study extensive observer data on the biological attributes of Chinook salmon by-catch (size and age composition) was used to estimate the impact on specific regional stock groups (RSGs) as defined given available genetic information. Given observed in-river age compositions, impact on Chinook salmon RSGs were evaluated under uncertain assumptions about age-specific oceanic natural mortality combined with the available genetics-based estimates of stock composition (accounting for between-year variability). Finally, assessment challenges including application of novel abundance indices within assessments and approaches to time-varying selectivity coefficients are discussed. This includes a novel computational approaches (within ADMB) to objectively specify process error variance terms.