Working Group on Mixed Fisheries Advice Methodology (WGMIXFISH-METHODS)

The ICES Working Group on Mixed Fisheries Methodology (WGMIXFISH-METHODS) met to progress work on the improvement and development of the mixed fisheries considerations.

The work addressed in 2026 included improving workflows for the advice process, presenting methodological advances and responding to issues encountered during WGMIXFISH-ADVICE 2025. The group reviewed the annual data call and processing procedures and discussed improved communication of mixed fishery advice products and collaborations with other working groups, notably the ICES Working Group on Economics (WGECON).

The primary development affecting data workflows is the planned introduction of the Regional DataBase and Estimation System (RDBES) to support stock assessments carried out in ICES. In 2027, RDBES will gradually replace InterCatch and the current ad hoc mixed fisheries data call, providing WGMIXFISH with data at a greater level of disaggregation than is currently possible. Whereas this presents an opportunity to improve the quality of mixed fisheries analyses carried out by the working group, the transition to RDBES is challenging because new processes are needed to assemble the inputs to mixed fisheries models. The working group continued the work of 2025 with a continued exploration of the RDBES data in the context of mixed fisheries.

Several methodological advances were presented, many of which address outstanding limitations of current approaches or stakeholder feedback received during mixed fisheries scoping workshops. These included the implementation of an age-structured mixed fisheries model framework for the Celtic Sea case study, the development of generic hindcast process as tool for model evaluation, and a presentation on how to speed-up mixed fisheries MSEs.

Finally, each case study addressed outcomes and issues encountered during the previous year in preparation for WGMIXFISH-ADVICE 2026.