Maritimes Region Snow Crab stock assessment for 2024

Abstract

Status In N-ENS, the modelled biomass (pre-fishery) of Snow Crab in 2024 was 2.7 kt placing the stock in the cautious zone. In S-ENS, the 2024 modelled biomass (pre-fishery) of Snow Crab in 2024 was 41.5 kt placing the stock in the healthy zone. In 4X (CFA24W), the modelled biomass (pre-fishery) of Snow Crab for the 2024–2025 season was 0.18 kt placing the stock in the critical zone. Trends There is a continued decrease in modelled biomass since 2022 in N-ENS, and since 2020 in S-ENS and 4X. The trends in fishing mortality estimates over the past few years show an increase in N-ENS and S-ENS. In 4X, the trend in fishing mortality showed a continued decrease since a peak in 2021 (2024–2025 fishing season ongoing at time of assessment). Recruitment for the male component of the population, the contribution to the fishable component, has been declining in N-ENS since 2019, has been relatively steady over the past ten years in S-ENS, and has shown a marked decrease in 4X since 2019. Environmental and Climate Change Considerations Bottom temperatures have reverted to cold-historical conditions in the last two years (2023 and 2024; below 5 degrees) after many years of high and variable conditions. Viable habitat for Snow Crab is highest in S-ENS even though temperatures are more stable in N-ENS. Even with ameliorations in temperatures in 2024, overall habitat viability has declined in all areas since 2019. Though 4X showed a marginal improvement in 2024, the overall trend has been downwards since 2010. Previous habitat space seems to have been overtaken by competitors and predators in 4X. Stock Advice Based on the 2024 modelled fishable biomass for each area, the strategies for exploitation rates, presented in the integrated fisheries management plan (DFO 2013), are 0–20% in N-ENS, 10–30% in S-ENS, and consideration of fishery closure for the 4X area. Other Management Questions An evaluation of consequences of various harvest levels in the 2025 fishery on stock abundance and exploitation rate was requested by Resource Management; however, this is not an output that is possible with the current modelling framework for Maritimes Region Snow Crab.