Working Group on Mixed Fisheries Advice (WGMIXFISH-ADVICE)

The ICES Working Group on Mixed Fisheries Advice (WGMIXFISH-ADVICE) held a hybrid-meeting to produce mixed fisheries forecasts for the Bay of Biscay, Celtic Sea, Iberian Waters, Irish Sea, and North Sea. These forecasts highlight the potential implications of single-stock (total allowable catch and effort) management on the catches of multiple stocks caught together in mixed fisheries. Mixed fisheries models consider past fishing patterns and catchability of the different fleets, and the catch advice produced by the single-stock advice groups, to provide quantitative forecasts of over- and under-exploitation of the different stocks given mixed fishery interactions. The mixed fisheries forecasts were produced using the “FCube” (Fleet and Fishery Forecasts) methodology for the Celtic Sea and Irish Sea, and the “FLBEIA” (Bio-Economic Impact Assessment using FLR) methodology for the Bay of Biscay, Iberian Waters, and North Sea.

The Bay of Biscay mixed fisheries projections consider the single-species advice of 13 stocks (ank.27.78abd, bss.27.8ab, hke.27.3a46-8abd, hom.27.2a3a4a5b6a7a-ce-k8, mac.27.nea, meg.27.7b k8abd, mon.27.78abd, nep.fu.2324, pol.27.89a, sdv.27.nea, sol.27.8ab, whb.27.1-91214, and whg.27.89a). Given the single-stock catch advice for 2026, the most limiting stock for demersal fisheries in the Bay of Biscay is mackerel, whose stock share is first reached for 11 of 23 defined fleets. The least limiting stock is horse mackerel (11 of 23 fleets).

The Celtic Sea mixed fisheries projections consider the single-species advice for 16 stocks (cod.27.7e-k, had.27.7b-k, whg.27.7b-ce-k, pol.27.67, nep.fu.16, 17, 19, 20–21, 22, and outside FUs, sol.27.7e, sol.27.7fg, mon.27.78abd, ank.27.78abd, meg.27.7b-k8abd, and hke.27.3a46-8abd). Given the single-stock catch advice for 2026, the most limiting stocks for demersal fisheries in the Celtic Sea are cod, haddock, and whiting, with 30 of 32 defined fleets choked by at least one these three stocks due to the zero-catch advice, and the fact that these three stocks are caught by almost all fisheries operating with demersal gears. The least limiting stock is black-bellied anglerfish (22 fleets), followed by hake (10 fleets).

The Iberian waters mixed fisheries projections consider the single-species advice for five stocks (ank.27.8c9a, hke.27.8c9a, lbd.27.8c9a, meg.27.8c9a, and mon.27.8c9a). Given the single-stock catch advice for 2026, the most limiting stock for demersal fisheries in the Iberian Waters is black-bellied anglerfish, with 10 of the 11 defined fleets reaching their black-bellied anglerfish quota with a lower effort than for the other stocks. The least limiting stock is white anglerfish (11 of 11 fleets).

The Irish Sea mixed fisheries model considers seven stocks (cod.27.7a, had.27.7a, ple.27.7a, sol.27.7a, whg.27.7a, nep.fu.14, and nep.fu.15). Irish Sea mixed fisheries projections were not produced for 2026 due to data unavailability or inconsistencies for multiple stocks (cod.27.7a, had.27.7a, and nep.fu.15) that required review or reanalysis by single-stock working groups, and there was insufficient time for revision of the Irish Sea model. Baseline model runs to ‘reproduce’ single-stock short-term forecast were carried out and showcase several of these inconsistencies.

The North Sea mixed fisheries projections consider the single-species advice for 21 stocks (bll.27.3a47de, cod.27.47d20, had.27.46a20, ple.27.420, ple.27.7d, pok.27.3a46, sol.27.4, sol.27.7d, tur 27.4, whg.27.47d, wit.27.3a47d, nep.fu.5, 6, 7, 8, 9, 10, 32, 33, 34, and 4outFU). Given the single-stock catch advice for 2026, the most limiting stock for demersal fisheries in the North Sea is cod, with 37 of 39 defined fleets choked by the zero-catch advice on this stock, and the facts that only two fleets do not have cod in their catch composition. The least limiting stock is whiting (33 of 39 fleets).

Additional work included contributions to a wide-ranging technical request on zero- and low-catch advice stocks. Stocks defined in the technical request and considered by WGMIXFISH-ADVICE were cod.27.7e-k, had.27.7b-k, whg.27.7b-ce-k, cod.27.47d20, ple.27.7d, and sol.27.7d.