The ICES Working Group on Mixed Fisheries Advice (WGMIXFISH-ADVICE) met remotely to produce mixed fisheries forecasts for the Bay of Biscay, Celtic Sea, Iberian Waters and North Sea. Mixed fisheries advice highlights the potential implications of single-stock (total allowable catch and effort) management on the catches of multiple stocks caught together in mixed fisheries. It takes into account past fishing patterns and catchability of the different fleets, and the TAC ad-vice produced by the single-stock advice groups, to provide quantitative forecast 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 on the “FLBEIA” (Fisheries Library Bio-Economic ImpaPrct Assessment) meth-odology for the Bay of Biscay, Iberian Waters and North Sea.
The Bay of Biscay mixed fisheries projections consider the single-species advice of 14 demersal stocks (ank.27.78abd, hke.27.3a46-8abd, hom.27.2a4a5b6a7a-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. Based on current fishing patterns and single-stock catch advice, the most limiting stock for Bay of Biscay demersal fisheries is pollack, whose quota is first reached for 15 of 22 defined fleets. The least limiting stock is black-bellied anglerfish (11 of 22 fleets).
The Celtic Sea mixed fisheries projections consider the single-species advice for 12 demersal stocks (cod.27.7e–k, had.27.7b–k, whg.27.7bce–k, nep.fu.16, 17, 19, 20–21, 22, and outside FUs, sol.27.7fg, mon.27.78abd, and meg.27.7b–k8abd). Based on mixed-fisheries considerations and single-stock catch advice, cod is the most limiting stock for Celtic Sea demersal fisheries. This is due to the zero-catch advice for cod and because almost all fisheries operating with demersal gears catch cod.
The Iberian waters mixed fisheries projections consider the single-species advice for 5 demersal stocks (ank.27.8c9a, hke.27.8c9a, lbd.27.8c9a, meg.27.8c9a and mon.27.8c9a). Based on mixed fisheries considerations and single-stock catch advice, hake is the most limiting stock for Atlantic Iberian waters demersal fisheries, corresponding to an undershoot of the advised catch for the other stocks considered in the mixed fisheries analysis. Conversely, anglerfish stocks are the least limiting stocks, corresponding to an overshoot of the advised catch for the other stocks. If fleets set their effort in order to catch their anglerfish stock shares, overshoot and reduction of SSB is more noticeable in hake and the four-spot megrim stock, possibly due to an increased technical interaction between this species and the anglerfish stocks.
The North Sea demersal mixed fisheries projections consider the single-species advice for 15 de-mersal stocks (cod.27.47d20, had.27.46a20, whg.27.47d, pok.27.3a46, ple.27.420, ple.27.7d, sol.27.4, tur 27.4, wit.27.3a47d, nep.fu.5–10, 32, 33, 34, and 4 outFU). Based on current fishing patterns and single-stock catch advice, the most limiting stock for North Sea demersal fisheries is cod, whose quota is first reached for 37 of 40 defined fleets. Whiting is the least limiting stock in 25 of 40 fleets making it overall the least limiting stock.
Additional work included progress towards the development of mixed fisheries advice for the Irish Sea, and contributions by the working group to the fisheries overviews for a number of regions and a technical request.