Stock status update of 4VWX Herring for the 2024 fishing season

Abstract

Maritimes Fisheries and Oceans Canada (DFO) Resource Management has requested that DFO Science conduct a stock status update of the Northwest Atlantic Fisheries Organization (NAFO) Divisions 4VWX Atlantic Herring (Clupea harengus) (henceforth referred to as 4VWX Herring) in support of the 2024 fishery. The last full assessment of 4VWX Herring was conducted in March 2022 (DFO 2022). As defined in the Terms of Reference, the objectives for this update were as follows: • Evaluate the indicators and assess the fishery with respect to the Limit Reference Point (LRP) for Southwest Nova Scotia/Bay of Fundy (SWNS/BoF) spawning component. • Update and review information on the other spawning components (Offshore Scotia Shelf, Coastal Nova Scotia, Southwest New Brunswick migrant juvenile fishery). • Update and evaluate the candidate Management Procedures (MPs) on the Reference Set of Operating Models (OMs) for the SWNS/BoF component. • Advise on the probability of rebuilding above the LRP over the projection period (2021–2045) for each candidate MP for the SWNS/BoF component. • Assess whether exceptional circumstances are triggered for the SWNS/BoF component. The stock status of the SWNS/BoF component is estimated by comparing the 3-year moving average of the acoustic index of spawning stock biomass for German Bank and Scots Bay to the LRP defined in terms of this acoustic index (Clark et al. 2012). It also accounts for turnover of spawners at these grounds (DFO 2018). For the SWNS/BoF component of 4VWX Herring, an assessment framework was conducted using a Management Strategy Evaluation (MSE) from 2019 to 2022 (Singh et al. 2020, Carruthers et al. 2023, Barrett 2023). The science advice for 2024 uses the 2022 assessment framework to evaluate whether candidate MPs have a high probability of rebuilding the SWNS/BoF component above the LRP, evaluate trade-offs among other management objectives, and assess whether exceptional circumstances are triggered. The analytical model was accepted for peer-review for the 2022 assessment (DFO 2022). However, Total Allowable Catch (TAC) advice for 2022 and 2023 was not based on an implemented MP, instead, one-year TACs were set for 2022 and for 2023. For other spawning components of 4VWX Herring, indicators of relative status and landings are reported herein based on methodologies presented in the 2018 stock assessment (DFO 2018). This Science Response Report results from the regional peer review of March 20, 2024, on the Stock Status Update of Herring in Northwest Atlantic Fisheries Organization (NAFO) Fishing Areas 4VWX.