Working Group on Methods of Fish Stock Assessments (WGMG)

The ICES Working Group on Methods of Fish Stock Assessment (WGMG) met in Lisbon, Portugal from 8–12 October 2012. The focus of this year’s meeting was to provide support to the ICES Strategic Initiative for Stock Assessment Methods (SISAM) by proposing both a selection of real datasets (both from within ICES and from other areas of the world) and the details of a stock assessment methods evalua-tion scheme that will make use of these selected datasets. A total of 14 datasets are put forward, reflecting a wide range of biological characteristics, data quality and availability issues, and assessment model types and problems. The evaluation scheme recommended is an amalgamation of three proposals submitted to the meet-ing, which approach the evaluation of assessment methods from different perspec-tives, ranging from robustness testing and investigating “grand questions” through simulations conditioned on real datasets, to a greater focus on model selection criteria (such as investigating the predictive ability of models). Aspects of the recommended evaluation scheme were trialled and have already yielded some informative results. A couple of novel model developments within the ICES community (a state-of-the-art web interface for facilitating all aspects of performing a stock assessment, and a framework for wide application of a flexible stock assessment model on data moder-ate stocks for which no assessments currently exists) are also presented.