The Workshop on the Development of Quantitative Assessment Methodologies based on Life-history traits, exploitation characteristics, and other relevant parameters for data-limited stocks (WKLIFE XI), chaired by Carl O'Brien (UK), Tobias Mildenberger* (Denmark) and Simon Fischer* (UK) met in Copenhagen, Denmark 16-20 January 2023 (with hybrid meeting access), to further develop methods for stock assessment, stock status, and catch advice for stocks in ICES Categories 2–6, including the clarification of key issues previously raised by the ICES’ Commu-nity when implementing methods developed by WKLIFE for use in the ICES’ advice.

Intersessional work had taken place ahead of the WKLIFE XI meeting and was presented during the workshop. The presentations defined the work programme for the workshop and the iden-tification of virtual subgroups; eight of which were identified within three Themes – Theme 1 (assessment methods), Theme 2 (challenges independent of assessment method) and Theme 3 (advice for stocks in ICES’ Categories 4-6, model diagnostics, control rules and management strategy evaluation).

This workshop report contains detailed responses to collated comments from the ICES’ commu-nity on the empirical harvest control rules for Category 3 data-limited stocks and surplus pro-duction models for Category 2 stocks; together with further guidance. However, WKLIFE XI decided not to update the ICES technical guidance for harvest control rules and stock assessments for stocks in categories 2 and 3 (published 20 May 2022) at this stage.

A draft roadmap was developed during the workshop for future data-limited research, assess-ment and management advice within ICES. The intended focus will be to make use of the best available science to further improve the provision of data-limited advice within ICES and to re-view new developments from both inside and outside of ICES; including FAO, RFMOs and sci-entists outside ICES’ membership. Topics include: data and their preparation, Categories 4-6 stocks including revisiting PSA (Productivity and Susceptibility Analysis), empirical indicators and harvest control rules (HCRs), length-based assessments, surplus production model assess-ments, data-limited reference points, simulation frameworks, short-lived and fast-growing spe-cies, and long-lived and slow-growing species, elasmobranchs, and sensitive and rare species. Timelines for delivery of the activities within the roadmap are to be identified at the next meeting of WKLIFE; together with prioritising tasks.