Évaluation de la crevette nordique (Pandalus borealis) et de la crevette ésope (Pandalus montagui) dans les zones d'évaluation est et ouest, février 2023

Abstract

The last full assessment was completed in 2021. This assessment has updated the stock status for Pandalus borealis and P. montagui in the Eastern Assessment Zone (EAZ) and Western Assessment Zone (WAZ), to incorporate survey and fishery data from the last two years. Limited predator-prey information, potential redfish competition, and oceanographic data were reviewed for additional ecosystem context. Pandalus borealis and P. montagui are distributed broadly over the Northwest Atlantic Ocean. The associated assessment areas, including the EAZ, WAZ and Shrimp Fishing Area 4 (SFA4), are connected through larval dispersal, but rates of exchange of adults are less understood. These linkages need to be considered to interpret fluctuations in biomass within and among assessment areas, even within the same year. The ocean climate in the NW Atlantic experiences fluctuations at decadal time scales, with potential impacts on availability of optimal Pandalid habitat and/or predator-prey interactions in the EAZ/WAZ. In 2022, bottom temperatures in the EAZ were lower than the 2006–2021 average for the first time since 2017, but they remained relatively high in the WAZ after the record high in 2021. The emergence of a large biomass of juvenile redfish in the EAZ over the last three years may have indirect (competition) and/or direct (future predation) impacts on the shrimp population. The magnitude and duration of these impacts are unknown. In both the EAZ and WAZ the stocks are currently assessed relative to established Limit Reference Points (LRPs) and previously proposed Upper Stock Reference points (USRs) in accordance with DFOs Precautionary Approach (PA) Framework.