Working Group on Widely Distributed Stocks (WGWIDE)

WGWIDE reports on the status and considerations for management of the Northeast Atlantic mackerel, blue whiting, Western and North Sea horse mackerel, Northeast Atlantic boarfish, Norwegian spring-spawning herring, striped red mullet (Subareas 6, 8 and Divisions 7.a-c, e-k and 9.a), and red gurnard (Subareas 3, 4, 5, 6, 7, and 8) stocks.2025 advice was drafted for seven of the stocks (excluding striped red mullet). Benchmark is proposed for 2027 for blue whiting while and Boarfish and both horse mackerel stocks were benchmarked in 2024. Mackerel and herring was benchmarked in 2025, and new assessment has been approved for both stocks.Northeast Atlantic Mackerel. This migratory stock is widely distributed throughout the Northeast Atlantic with significant fisheries in several ICES subareas. The assessment conducted in 2025 was based on the data and configuration agreed during the 2025 benchmark and incorporates updates to the commercial catch, tagging index, swept area index, and egg survey index. Advice is given based on stock reference points which were updated during the 2025 benchmark. SSB has been declining since 2014 and is below Blim in 2025. Fishing mortality has been increasing since 2019 and above FMSY since 2022.Blue Whiting. This pelagic gadoid is widely distributed in the eastern part of the North Atlantic. The current assessment configuration (inter-benchmark in 2016) uses preliminary catch and sampling data along with the acoustic survey data from the current year. The 2025 update assessment indicates that SSB has been increasing until 2024 following strong recent recruitment and is well above MSY Btrigger, even though a decline in SSB is estimated since 2024. Fishing mortality has been above FMSY since 2014.Norwegian Spring Spawning Herring. This stock is migratory, spawning along the Norwegian coast and feeding throughout much of the Norwegian Sea. The assessment conducted in 2025 was based on the data and configuration agreed during the 2025 benchmark. SSB has been declining since 2007, except for an increase in 2021-2022 which was due to the strong 2016 year-class entering the SSB. Fishing mortality has been below FMSY since 2019 (except for 2020). Recruitment in 2016-2020 is estimated to be below average and SSB is below MSY Btrigger in 2025 and decreasing further in 2026. However, recruitment in 2021 and 2022 is estimated to be above average, and SSB is forecast to be above MSY Btrigger in 2027 if the management strategy is followed in 2026.Western Horse Mackerel. The western stock of horse mackerel is distributed throughout ICES subareas 4,6,7,8 and 9. Following a benchmark in 2017, the stock is assessed using the Stock Synthesis integrated assessment model and improvements to the assessment were done in the 2024 benchmark. Stock reference points were revised in 2024 and new reference points were estimated. Following a period of declining SSB, there has been a modest upward trend since 2015, albeit from a low level. The 2025 assessment indicates that SSB is above MSY Btrigger in 2025 and 2026. The assessment has been displaying significant retrospective bias, but changes made to the assessment in the 2024 benchmark have improved the diagnostic analyses compared to the previous model.North Sea Horse Mackerel. In the 2024 benchmark, a SAM assessment was set up for the North Sea horse mackerel. The new assessment includes catch data, a commercial CPUE index and a combined SSB index from two ground fish surveys. The change resulted in the stock being moved from a category 3 to a category 1 stock and a new advice for 2025 replaced the advice issued in 2023. New reference points were estimated in the 2024 benchmark, but some of the reference point (FMSY, Fpa) could not be reliably estimated. The SSB is estimated to be below Blim in 2025 and forecast to be below Blim in 2026 and to remain below Blim in 2027 even with zero catch in 2026. Based on the MSY approach the advice for 2026 is therefore for zero catch.Northeast Atlantic Boarfish. Boarfish is a small, pelagic, planktivorous, shoaling species, found over much of the Northeast Atlantic shelf but primarily in ICES subareas 4,6,7 and 8. The directed fishery occurs primarily in the Celtic Sea and developed during the early 2000s, initially unregulated before the introduction of a TAC in 2011. In the 2024 benchmark a length based analytical assessment in Stock Synthesis 3 was set up including catch data, a combined acoustic survey biomass index, a combined ground fish survey biomass index, and new reference points were estimated. Based on the new assessment, the stock was moved from category 3 to category 1 and a new advice for 2025 replaced the advice issued in 2023. The current assessment indicates that, following a decline from 2012 to 2019, SSB has been increasing sharply in recent years following high recruitment in 2017 to 2019, but declining since 2024. SSB is estimated to be well above MSY Btrigger in 2025 and forecast to remain above MSY Btrigger in 2026 and 2027.Northeast-Atlantic Red Gurnard. This stock was first considered by WGWIDE in 2016 with advice issued biennially. The assessment was benchmarked in 2021 and a survey-based relative biomass indicator was developed. The 2025 update assessment continues to show the indicator fluctuating without trend since 2010. However, large uncertainties remain with regard to landings data due to poor resolution at the species level and reported discarding levels vary widely.Striped Red Mullet in Bay of Biscay, Southern Celtic Seas, Atlantic Iberian Waters. No assessment is available for this stock and information on abundance and exploitation level is limited with advice given triennially on the basis of the precautionary approach. However, there are a number of research projects underway which will inform the planned benchmark and potential upgrade of the assessment category.