Second Scoping Workshop on Next Generation of Mixed Fisheries Advice (WKMIXFISH2)

The objective of the Second Scoping workshop on the next generation of mixed fisheries advice (WKMIXFISH2) was to continue a dialogue with advice recipients, stakeholders, and scientists on developing mixed fisheries science and advice to meet management needs. The meeting aimed at establishing the current use and utility of mixed fisheries considerations and identifying priority areas for future development.

There was overall support for scenario-based advice on the consequences of mixed fisheries interactions given incompatibilities among single stock advice catch limits. Mixed fisheries considerations are currently used as supplementary information to single stock advice, providing managers with a directional tool when considering catch limits that protect vulnerable stocks. This focus on general trends, rather than specific values in the mixed fisheries scenario forecasts, is due in some cases to a combination of uncertainties associated with mixed fisheries interactions among fleets and metiers, considerations of economic trade-offs, as well as the potential behavioural response to changing catch opportunities. A clearer presentation of model assumptions was seen as important for framing the interpretation of mixed fisheries considerations and these factors. For example, mixed fisheries forecasts highlight incompatibilities in single stock advice under the assumption that future fishing will resemble recent historic patterns. In addition to influencing catch limits, it was recognised that the scenario forecasts could be used in conjunction with other data and advice products to aid in the development of adaptive strategies to changing fishing opportunities.

Discussions on potential improvements focussed on model and scenario assumptions that can influence technical interactions among fleet and metiers. These included fleet and metier definitions, quotas share distributions among fleets, effort shares among metiers in each fleet and the development of alternate scenarios. In addition to the ongoing review of these aspects, it was suggested that further transparency and feedback from stakeholders would be beneficial, especially in the definition of fleets and metiers that best capture technical interactions. Other areas of development included the potential of mixed fisheries models to provide further information on impacts to bycatch stocks and additional scenarios for assessing stock rebuilding strategies, and the incorporation of routines to understand uncertainty in the model forecasts to input data and conditioning. 

There was a clear call for the availability of more detailed information on spatial dynamics in mixed fisheries and on supplemental advice products that can help inform mitigation strategies to overcome imbalances in TACs.

The workshop identified several areas where developments can be made to the current advice product, as well as additional advice products that could support management decisions. There is now planned technical work to develop these ideas before the subsequent workshop (WKMIXFISH3) in March 2024.