A decade of ICES experience demonstrates that adaptive advisory systems underpin effective data-limited fisheries advice

Providing scientifically credible advice for data-limited fisheries remains one of the major challenges in sustainable fisheries management. Although the Northeast Atlantic benefits from extensive monitoring programmes and well-established advisory institutions, 157 of the 271 stocks (58%) assessed by the International Council for the Exploration of the Sea (ICES) in 2024 were data-limited (ICES categories 2–6), still outnumbering data-rich stocks more than a decade after dedicated efforts began. This paper synthesises the experience from the fourteen ICES Workshops on the development of quantitative assessment methodologies based on life-history traits, exploitation characteristics, and other relevant parameters for data-limited stocks (WKLIFE) and associated workshops to examine how data-limited fisheries advice has evolved in practice. We identify five lessons from these workshops: (1) tiered frameworks and risk equivalence enable precautionary advice across differing levels of data availability; (2) effective advice depends on making the best use of available information; (3) rigorous evaluation is essential for credible advice; (4) implementation is as important as methodological innovation; and (5) continuous learning and adaptation sustain effective advisory systems. Across these lessons we argue that data-limited advice should be judged by its demonstrated performance, not by the amount of data or the complexity of the model behind it. This also sets a limit: for the most data-poor stocks, where performance cannot be tested, it is more useful to be clear about the bounds of reliable advice than to imply a false precision. We identify priorities for future development, including refinement of assessment frameworks, improved integration of heterogeneous data sources, better quantification of uncertainty, and continued investment in implementation and institutional capacity. Although these lessons are drawn from the ICES experience, they provide a general framework for strengthening fisheries advice wherever conventional stock assessments are constrained by limited data.