A catch per unit effort - soak time model for the Bristol Bay red king crab fishery, 1991-1997

Postseason commercial fisheries data are used to estimate a catch per unit effort (CPUE) - soak time relationship for the 1991-1993 and 1996-1997 Bris tol Bay red king crab (Paralithodes camtschaticus) fishery in order to gain regulatory and in-season management insight. Use of commercial fishery dat a allows our model to capture the influence of biological and environmental effects as well as behavioral responses of crabbers to changing natural an d regulatory conditions on CPUE. However, data deficiencies present a varie ty of estimation challenges, especially when the data are derived from neit her a contemporaneous nor a scientifically designed sample of the fleet. A statistical framework for dealing with such challenges is illustrated in th is paper. This research uncovered three major results. First, data pooling guided by recursive estimation/hypothesis testing is shown to be essential. Second, the analysis provides insight into CPUE response to changing condi tions, whether biological, ecological, or policy induced. Third, it is appa rent that more complete and contemporaneous collection of commercial fisher ies data is critical to refine the estimation of CPUE - soak time relations hips. Then, it may be possible to isolate the inter- and intra-seasonal inf luence of biological and environmental effects as well as behavioral respon ses of crabbers to changing natural and regulatory conditions.