The Pelagic Advisory Council (PelAC) has called on the EU Commission for a benchmark on the Northeast Atlantic Mackerel stock
Pelagic Advisory Council Pushes for Comprehensive Data Collection Ahead of 2025 Mackerel Benchmark
The Pelagic Advisory Council (PelAC) has released key recommendations in preparation for the upcoming benchmark on Northeast Atlantic mackerel, set for March 2025. In a detailed report sent to the European Commission, PelAC emphasised the need for improved data collection, enhanced scientific surveys, and the inclusion of ecosystem and climate-related factors to ensure a more accurate assessment of mackerel stocks.
The report is based on discussions from the PelAC Focus Group meeting on September 12, 2024. It highlights several critical issues and proposes actions to improve the understanding and management of the Northeast Atlantic mackerel population, a species of significant economic and environmental importance for European fisheries.
Uncertainties in Stock Data
PelAC has raised concerns over persistent uncertainties in stock assessments, particularly around data collection methods and geographic coverage. The council noted that several key data sources, including recruitment indices, trawl surveys, and tagging data, have inconsistencies that could undermine the accuracy of current models.
One major issue is the underrepresentation of mackerel in certain areas due to incomplete surveys, especially in the expanding northern spawning grounds. PelAC recommends revising the methods used in existing surveys and improving geographic coverage to capture a fuller picture of mackerel distribution. Additionally, PelAC stressed the need for further investigation into age-reading errors and the influence of natural mortality (M), a parameter which has remained constant at 0.15 in most models but may not fully reflect biological realities.
Stakeholder Involvement and Industry-Led Data Collection
A central theme of the recommendations is the integration of stakeholder insights, particularly from fishers, into data collection efforts. PelAC has been working on developing a fishers’ survey model, which was trialled in an ICES workshop in October 2023. The council suggested that fishers’ observations be used to complement scientific surveys, with industry self-sampling data included in the benchmark assessment.
Ashley Wilson, a key participant in the discussion, highlighted the importance of drawing on industry-collected data, which could provide a valuable cross-check for official stock assessments. PelAC also proposed organising more workshops and informal meetings with ICES to encourage collaboration between fishers and scientists, a move that could improve both data quality and stakeholder engagement.
The Role of Climate Change
PelAC has also pointed out the growing influence of climate change on mackerel behaviour, distribution, and stock dynamics. Although the upcoming 2025 benchmark will not focus on climate-related impacts, PelAC believes that long-term management strategies must account for these changes. Several members of the focus group, including Justyna Zajchowska and Jose Beltran, called for more research into how warming seas and changing ecosystems are affecting mackerel stocks, emphasising that this should be a future priority.
Expanding Scientific Surveys and New Data Methods
One of the main recommendations is the expansion of scientific surveys, particularly the inclusion of alternative methods such as acoustic surveys and the Daily Egg Production Method (DEPM). PelAC highlighted the limitations of existing egg surveys, noting that they may not fully capture mackerel spawning behaviours, especially as the spawning season shifts due to climate change.
The focus group also discussed the use of acoustic surveys to assess mackerel stock biomass. Claus Reedtz-Sparrevohn, a key presenter at the meeting, suggested that commercial vessels equipped with modern acoustic technology could be used to gather more accurate data on mackerel schools, especially in the North Sea. This proposal could be supported by both industry stakeholders and ICES.
Next Steps for the 2025 Benchmark
The upcoming benchmark will be a critical opportunity to address these concerns and improve the overall stock assessment process. PelAC has urged that more attention be given to reducing uncertainties in data sources and integrating a wider range of biological and environmental factors into the model.
The focus group also called for prioritising the development of a Management Strategy Evaluation (MSE) framework, which would allow for the testing of various management strategies to assess their impact on mackerel stock sustainability. This approach, if implemented, could help ensure that future quotas and conservation measures are based on robust scientific evidence and take into account the changing dynamics of the marine ecosystem.
Final Recommendations
PelAC’s recommendations underscore the need for a more comprehensive and collaborative approach to managing Northeast Atlantic mackerel. As the 2025 benchmark approaches, the council hopes that their proposed actions will lead to improved data collection, greater stakeholder involvement, and more accurate stock assessments. With mackerel playing a vital role in European fisheries, the outcome of the benchmark will have significant implications for both the environment and the fishing industry.
The final recommendations will be submitted to ICES and the European Commission, with the hope that they will shape the future of mackerel management in the Northeast Atlantic.