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Generic Harvest Control Rules for European Fisheries. Rainer Froese, Trevor A. Branch, Alexander Proelß, Martin Quaas, Keith Sainsbury & Christopher Zimmermann Accepted in Fish & Fisheries. Acronyms. B msy is the biomass that can produce the maximum sustainable yield (UNCLOS, UNFSA)
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Generic Harvest Control Rules for European Fisheries Rainer Froese, Trevor A. Branch, Alexander Proelß, Martin Quaas, Keith Sainsbury & Christopher Zimmermann Accepted in Fish & Fisheries
Acronyms • Bmsy is the biomass that can produce the maximum sustainable yield (UNCLOS, UNFSA) • Fmsy is the corresponding fishing mortality • Blim is the biomass below which recruitment is reduced and collapse possible • Bpa is a biomass slightly above Blim but far below Bmsy
Cod, Eastern Baltic Bmsy Bpa Blim Froese & Proelß Fish & Fisheries 2010
European Fisheries are Mismanaged • 24% are threatened by collapse (B < Blim) • 31% are near threatened (Blim > B < Bpa) • 45% are not threatened (B > Bpa) • But only 3-4 of these stocks have B > Bmsy and F < Fmsy , i.e., comply with UNCLOS and UNFSA • ICES since 2010 gives estimates of Fmsy but not MSY or Bmsy • Less than half of the stocks are assessed
HCR 1: Reference and Trigger Biomass The reference biomass Bmsy for the subsequent rules and reference points is the biomass that can produce the maximum sustainable yield. This biomass also acts as a trigger when stocks fall below this level.
HCR 2: Target Biomass The target biomass, to be achieved on average over approximately 5 years, is 1.3 Bmsy. The target biomass can be increased as required by economic, ecosystem or other considerations.
HCR 3: Limit Biomass The limit biomass Blim, which is to be avoided with a high probability, is 0.5 Bmsy A higher biomass limit may be set for species with low resilience to exploitation.
HCR 4: Total Allowable Catch Fisheries are managed by a total allowable catch (TAC). A maximum TAC is set for each stock so that the respective target biomass is maintained on average. This maximum TAC may be taken as long as biomass fluctuations remain above Bmsy.
HCR 5: TAC Reductions If the biomass falls below Bmsy, then the TAC is linearly reduced, as a function of biomass, to reach zero catch at Blim.
HCR 6: Mixed Fisheries In fisheries where several target species are caught with the same gear, the maximum TACs for the respective stocks will be set such that the most sensitive stocks do not fall below Bmsy on average over five years, with a high probability of not falling below Blim.
HCR 7: Discard No discard of commercially exploited species will be allowed, except for species with a demonstrated high discard survival rate.
HCR 8: Bycatch Ecological risk assessment will be conducted on bycatch species and to assess potential damage to the environment caused by fishing, with respective measures to be taken to minimize risk.
HCR 9: Size structure The mean size and age in the catch will be adjusted to minimize changes in age structure caused by fishing, and to reduce the effects of fisheries-induced unnatural selection.
Status of European Stocks Move stocks here. Landings may then be 60% higher Froese et al., accepted in FAF
Cod, Eastern Baltic BMSY MSY Froese & Proelß Fish & Fisheries 2010
Thank You Rainer Froese IFM-GEOMAR rfroes@ifm-geomar.de