A Modified Catch-Length Analysis Model for Golden King Crab (Lithodes aequispinus) Stock Assessment in the Eastern Aleutian Islands

A Modified Catch-Length Analysis Model for Golden King Crab (Lithodes aequispinus) Stock Assessment in the Eastern Aleutian Islands

M.S.M. Siddeek, David R. Barnard, Leslie J. Watson, and Robert K. Gish

A Modified Catch-Length Analysis Model for Golden King Crab (Lithodes aequispinus) Stock Assessment in the Eastern Aleutian IslandsThis is part of Fisheries Assessment and Management in Data-Limited Situations
PDF    
To download the free PDF [495.5 KB], please enter:
-or-

Description

The golden king crab (Lithodes aequispinus) has provided a valuable fishery in the Aleutian Islands region during the past two decades. Despite their economic importance, the Aleutian Islands golden king crab stock has not been surveyed annually, biological data are limited, and assessment models are lacking. As an initial assessment attempt, we applied a modified version of the catch length analysis method to observer data of males in association with total catch and effort data to estimate total legal male (≥ 136 mm carapace length, CL) and total male recruit (≥ 101 mm CL) abundances, and legal male harvest rate. We used the 1996-2001 data from catches in the eastern Aleutian Islands to determine these parameters. The estimated male recruit abundance fluctuated while estimated legal male abundance increased from 1996 to 2000 and slightly decreased in 2001 for the best fit model. The estimated legal male harvest rate at the time of the fishery decreased from 99% in 1996 to 52% in 2001. These findings should be treated cautiously because of the short history of data sets and lack of independent and reliable estimates of some vital biological parameters. The modeling procedure, however, demonstrated the feasibility of using observer data in stock assessment when no annual stock surveys are available.

Item details