Working Group on Mixed Fisheries Methodology (WGMIXFISH-METHODS)

31/08/2022: minor edits - Figure 4.9

21/11/2022: Annex 5 removed

The ICES Working Group on Mixed Fisheries Methodology (WGMIXFISH-METHODS) met to progress work on the improvement and development of the mixed fisheries advice. In this report the group provides a summary of the work completed in 2022.

The work addressed included improving workflows for the advice process, presenting methodological advances, developing new ecoregions and responding to issues encountered during WGMIXFISH-ADVICE 2022. Additionally, plans for a second scoping workshop were discussed and the contribution of WGMIXFISH to mixed fisheries information in the Fisheries Overviews was reviewed.

A key methodological advance used data on quota exchanges between countries to update the Min mixed fisheries scenario to address concerns over choking behaviour in fleets that generally do not entirely consume their initial quota allocation. This update is predicated on the assumption that when TAC changes become restrictive, the usual quota exchanges will become less likely.

An Irish Sea model has been in development for several years and a mature version was pre-sent-ed. A formal review process has been initiated to evaluate this model with a timescale consistent with incorporating this ecoregion into the formal mixed fisheries advice process for 2022.

To help improve the understanding of the main outputs from the mixed fisheries model a new design for the headline “advice” plot was approved at this meeting. This new design presents the results from each mixed fisheries scenario for a particular stock. This should enable stake-holders to draw easier comparisons between the different scenarios presented for their stock of interest.

Future work ahead of next year’s meeting will focus on finalising the plans initiated at this meeting for a second scoping workshop and refining the contribution of WGMIXFISH to mixed fisheries information presented in the Fisheries Overviews.