Terms of Reference

Units 1 and 2 Redfish (Sebastes mentella and S. fasciatus) Stocks Assessment in 2024

Regional Peer Review - Quebec Region

March 11-14, 2025

Mont-Joli, QC

Chairperson: Daniel Duplisea

Context

The Fishery management sector of Fisheries and Oceans (DFO) has requested science advice for Units 1 and 2 Redfish. Units 1 and 2 Redfish stocks are prescribed under section 6 of the Fisheries Act. Redfish in Units 1 and 2 consists of two different stocks: Sebastes mentella and S. fasciatus. These stocks are distributed in the Gulf of St. Lawrence, as well as in the Laurentian Channel and Laurentian Fan regions.

Based on the most recent science response (DFO 2024), the S. mentella stock was considered to be the healthy zone with a spawning stock biomass (SSB) of 2,302 kilotonnes (kt), while the status of S. fasciatus remained uncertain with a SSB estimated at 181 kt. Potential removals were determined based on estimates of natural mortality rate and the biomass of fish over 22 cm. In light of uncertainties concerning the productivity of the stock, a realistic range of potential removals was estimated , varying between 88 kt and 318 kt, with a median value of 276 kt for S. mentella for the 2024–2025 fishing season. Given the low levels of recruitment and growth observed in recent years, even in the absence of fishing, Redfish biomass is expected to decrease in upcoming years due to natural mortality.

Objectives

• Update the abundance and biomass indices from surveys, including size structure and geographic distribution of catches;
• Determine stock status and spawning stock biomass trends relative to the reference points for S. mentella and S. fasciatus based on the survey in the northern Gulf of St. Lawrence;
• Advise on the range of potential removals of S. mentella and S. fasciatus in Units 1 and 2 for the 2025-2026 fishing season;
• Describe the Gulf of St. Lawrence ecosystem, including relevant summaries of oceanographic conditions and ecological interactions (e.g. predator, prey);
• Describe the biology and diet of Units 1 and 2 Redfish;
• Describe Redfish fisheries in Units 1 and 2, including landings per NAFO divisions, months and gears, and length frequencies;
• Describe bycatch in the Redfish fisheries based on logbook and at-sea-observer data, including bycatch percentages (bycatch biomass/Redfish biomass), distribution maps, depth profiles, and length frequency for the main species of concern;
• Improve the approach to identify S. mentella and S. fasciatus based on anal fin ray counts;
• Compare the Léry Charles and the CCGS John Cabot catches for Unit 2 survey in 2024;
• Identify key knowledge gaps and research priorities.

Expected Publications

• Science Advisory Report
• Research Document

Expected Participation

• Fisheries and Oceans Canada (DFO) sectors
• Provincial governments
• Academia
• Indigenous communities/organizations
• Fishing industry
• Environmental non-government organizations

References

• DFO. 2024. Unit 1 Redfish (Sebastes mentella and S. fasciatus) Update in 2023. DFO Can. Sci. Advis. Sec. Sci. Resp. 2024/008.