Working Group on Mixed Fisheries Advice (WGMIXFISH; Outputs from 2020 Meeting)

Abstract

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 advice 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 North Sea, and on the “FLBEIA” (Fisheries Library Bio-Economic ImpaPrct Assessment) methodology for the Bay of Biscay and Iberian Waters. The Bay of Biscay mixed fisheries projections consider the single-species advice of 14 demersal stocks (ank.27.78abd, bss.27.8ab, hke.27.3a46-8abd, hom.27.2a4a5b6a7a-ce-k8, mac.27.nea, meg.27.7b-k8abd, mon.27.78abd, nep.fu.2324, rjc.27.8, rjn.27.678abd, rju.27.8ab, sdv.27.nea, sol.27.8ab and whg.27.89a. Mixed-fisheries projections for 2021 indicate that there is no single stock that restricts all fleets. Smooth-hound (sdv.27.nea), Norway lobster (nep.fu.2324) and both anglerfishes (ank.27.78abd and mon.27.78abd) are the least limiting stocks, resulting in an overshoot of the advised catch for the other considered stocks. 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). The results of the mixed fisheries projections show that cod (cod.27.7e–k ) limits all fleets due to the zero catch advice for cod and that all fleets catch cod to a greater or lesser extent. Sole (sol.27.7fg) and Norway lobster (nep.fu.16, 17, 19, 20–21, 22) are the least limiting stocks corresponding to an overshoot of the advised catch for the other considered stocks. 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). The result of the mixed fisheries projections indicate that hake (hke.27.8c9a) will be the most limiting stock, corresponding to an undershoot of the advised catch for the other stocks. Anglerfish stocks (ank.27.8c9a and mon.27.8c9a) are the least limiting stocks, corresponding to an overshoot of the advised catch for the other considered stocks. The North Sea demersal mixed fisheries projections consider the single-species advice for 15 demersal 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). The results of the projections indicate that cod (cod.27.47d20) will be the most limiting stock for certain fleets, corresponding to an undershoot for the advised catch for the other stocks considered in the mixed fisheries analysis. The “range” scenario suggests that the potential for mixed-fisheries mismatch would be lowered with a 2021 TAC in the lower part of the FMSY range for North Sea plaice (ple.27.420), saithe (pok.27.3a46), and sole (sol.27.4), and at the highest possible value for cod (cod.27.47d20) in accordance with the MSY approach and the EU multiannual plan.