Working Group on the Assessment of Demersal Stocks in the North Sea and Skagerrak (WGNSSK).

The main terms of reference for the ICES Working Group for the Assessment of Demersal Stocks in the North Sea and Skagerrak (WGNSSK) were to update, quality check, and report relevant data for the working group, to update and audit the assessment and forecasts of the stocks, to produce a first draft of the advice on the fish stocks, and to prepare planning for benchmarks in future years. Ecosystem changes have been analytically considered in the assessments for cod, haddock, and whiting in the form of varying natural mortalities estimated by the ICES Working Group on Multispecies Assessment Methods (WGSAM). Conservation status advice was considered but WGNSSK did not identify any conservation aspects for its stocks. From this year the Nephrops stocks have been removed from WGNSSK and will be assessed by a new working group WGNEPH. Recent benchmarks A benchmark that involved WGNSSK stocks was organized in 2024–2025. The WKBNSCS benchmark for North Sea turbot (tur.27.4) and for eastern English Channel plaice (ple.27.7d) evaluated the appropriateness of data and methods to determine stock status. State of the stocks The main impression in recent years is that fishing pressure has been reduced substantially for many North Sea stocks of roundfish and flatfish compared to the beginning of the century. Five stocks with agreed reference points (category 1 stocks) have SSB higher than MSY Btrigger (haddock in 4, 6.a and 20, plaice in 4 and 20, turbot in 4, whiting in 4 and 7.d and witch in 3.a, 4 and 7.d). The SSB of saithe in 3.a, 4 and 6 is just above Blim. The SSB of sole in 7.d and plaice in 7.d is below Blim. Several North Sea stocks are exploited at or below FMSY levels (haddock in 4, 6.a and 20, plaice in 4 and 20, sole in 7.d, turbot in 4, whiting in 4 and 7.d, and witch in 3.a, 4 and 7.d); however, plaice in 7.d, and saithe in 3.a, 4 and 6 are fished above FMSY. An important feature is that recruitment remains poor compared to historical average levels for most gadoids, although there have been signs of strong recruitment for whiting in most recent years. However, recruitment in 2024 appears to be still low for the gadoids and lower than previous years for flatfish stocks, with the exception of plaice in 4 and 20, turbot in 4, and whiting in 4 and 7d. WGNSSK is also responsible for the assessment of several data-limited stocks (category 2+ stocks) that are mainly bycatch in demersal fisheries; brill in 3.a, 4 and 7.d–e, lemon sole in 3.a, 4 and 7.d, dab in 3.a and 4, flounder in 3.a and 4, turbot in 3.a, whiting in 3.a, grey gurnard in 3.a, 4 and 7.d, striped red mullet in 3.a, 4, 7.d, pollack in 3.a and 4 and saithe in 7-10. Annual advice is required for brill in 3.a, 4 and 7.d–e, turbot in 3.a, and lemon sole in 3.a, 4 and 7.d. Biennial advice is required for striped red mullet in 3.a, 4 and 7.d, flounder in 3.a and 4, grey gurnard in 3.a, 4 and 7.d (due in 2026), and whiting in 3.a (due in 2026). Triennial advice is now required for dab in 3.a and 4, saithe in 7-10, and pollack in 3.a and 4 (due in 2027). Category 2–6 fish stocks: In 2025, new advice has been produced for bll.27.3a47de (category 2), for dab.27.3a4, fle.27.3a4, lem.27.3a47d, mur.27.3a47d (category 3), and pok.27.7-10 (category 5). Advice was produced following the WKLIFE X rules. Advice was not provided for gug.27.3a47d, whg.27.3a (category 3), and pol.27.3a4 (category 5). Advice for cod.27.46a7d20, sol.27.4 and tur.27.3a was postponed to the autumn.