État des stocks des sébastes (Sebastes mentella et S. fasciatus) de l'unité 1 en 2021

Abstract

The Redfish fisheries in Unit 1 target two species, Sebastes mentella and S. fasciatus. Unit 1 includes Northwest Atlantic Fisheries Organization (NAFO) Divisions 4RST and from January to May Subdivisions 3Pn4Vn. Unit 2 includes Subdivisions 3Ps4V4Wfgj, and from June to December Subdivisions 3Pn4Vn. Although considered the same stocks as Unit 1, Unit 2 is not presented in this document. Between the mid-1950s and 1993, the fishery was marked by three intense exploitation episodes that were closely linked to the recruitment of one or several strong year-classes. A sudden drop in landings and the absence of strong recruitment led to the establishment of a moratorium in 1995 in Unit 1. Redfish fishing is still under moratorium in Unit 1 and an index fishery has been authorized since 1998. The total allowable catch (TAC) for this fishery has been 2,000 tonnes (t) per management year since 1999. In 2018, an experimental fishery was established with an additional allocation of 2,500 t for 2018–2019, 3,950 t for 2019–2020, 3,681 t for 2020–2021, and 5,463 t for 2021–2022, which can be harvested all year. The objectives of the experimental fishery were to target S. mentella, which is more abundant than S. fasciatus, to investigate ways to limit bycatch and the harvesting of undersize Redfish, and to better understand the spatiotemporal distribution of Redfish and bycatch species. According to surveys conducted in Unit 1, abundance and biomass indices for S. mentella and S. fasciatus were low and stable since the mid-1990s. Abundance of juvenile Redfish from the 2011 to 2013 cohorts has increased substantially in the Fisheries and Oceans Canada (DFO) research surveys. These cohorts are the most abundant ever observed in the northern Gulf of St. Lawrence (nGSL). The minimum trawlable biomass of both species combined is among the highest values of the time series and was estimated at 3.2 million t in 2021 with a modal size of 24 cm, slightly over the regulatory minimum size of 22 cm. In support of the Redfish stock assessments (S. mentella and S. fasciatus) of Units 1 and 2 in 2022, this document describes the data and methods used to analyse the status of the stocks found in Unit 1.