Stock status update of unit 3 redfish for 2022

Abstract

A 10,000 metric tonnes (t) Total Allowable Catch (TAC) was implemented for Unit 3 Redfish (4X+ 4Wdehkl) in 1993 based on the 1991 TAC for the previous management unit (North Atlantic Fisheries Organization (NAFO) Subarea 4VWX), prorated by historical (1981–1990) catches in the Statistical Unit Areas which comprise Unit 3 (Atkinson and Power 1991). This TAC was maintained from 1993–1998 based on conclusions from a series of stock status reports which indicated that stock conditions were not expected to decline in coming years (Branton and Halliday 1994, Branton 1995, 1996, 1997, 1998). In 1999, the TAC was reduced to 9,450 t, followed by a reduction to 9,000 t in 2000 due to lower catch rates in 4W and a shift in fishing effort from 4W to 4X (Branton 1999). The TAC was further reduced to 8,000 t in 2022. Conservation measures for Unit 3 Redfish currently include protocols for protecting small fish below the minimum size of 22 cm fork length (FL) (i.e., closure areas, small fish amounts not to exceed 15% of catch/trip), 100% dockside monitoring and electronic vessel monitoring (VMS), mandatory hail out and hail in, and a target level of 10–20% at-sea observer coverage. Information on the status of Unit 3 Redfish (i.e., distribution, abundance, biomass) from 1999–2002 was provided through a series of Canadian Science Advisory Secretariat (CSAS) Research Documents that included a synopsis of the Fisheries and Oceans Canada (DFO) Summer Research Vessel (RV) Survey trends back to 1970 for selected groundfish stocks (e.g., Branton and Black 2002). Since 2009, the status of Unit 3 Redfish has been updated through a series of CSAS Science Responses (e.g., DFO 2017a), based on RV survey trends in biomass and abundance. Following the development of biological reference points consistent with the precautionary approach (DFO 2012), the DFO Summer RV Survey Trends Science Responses from 2014 to 2019 have included plots of the mature biomass index for redfish > 22 cm FL relative to the Upper Stock Reference (USR; 80% of Biomass at Maximum Sustainable Yield [Bmsy] proxy) and the Limit Reference Point (LRP; 40% of Bmsy proxy) (DFO 2020). In 2015, a zonal peer review of the assessment framework for Units 1–3 Redfish (DFO 2017b) included a detailed review of Unit 3 Redfish stock status; however, this information has not yet been published, and as a result, there has been no new information available on the fishery for several years. In 2018, DFO Resource Management asked Science to review biological and fishery information on Unit 3 Redfish, to evaluate the status of the stock relative to adopted reference points (DFO 2012), and report on bycatch of non-target species in the Unit 3 Redfish Fishery (DFO 2019). A science response was provided in 2020 (DFO 2021) but not in 2021 as no new RV survey data were available This science response provides a stock status update of Unit 3 Redfish using the most up to date landings and RV survey data. This Science Response Report results from the regional peer review of December 6–7, 2022, on the Update of Stock Status for Unit 3 Redfish.