Assessment of the Northern Gulf of St. Lawrence (3Pn, 4RS) Atlantic Cod Stock in 2022

Abstract

For the 2021-2022 fishing season, the total allowable catch was 1,000 t, which corresponded to an available commercial fishing allocation of 641 t. For the 2022-2023 season, there was no directed Atlantic cod commercial fishery. Preliminary landings, including bycatch and sentinel surveys catches, totaled 677 t in 2021-2022 and 132 t in 2022-2023. Recreational fishing was authorized in 2022 for a maximum of 39 days distributed between June and October (variable according to the zones). There is no reporting of removals from this fishery. The abundance index from the DFO research survey was above the series mean and increasing since 2020. The 2018 cohort, which has been observed annually in the survey since 2019, appears to be the most abundant since the early 1990s. The abundance and biomass indices from the sentinel trawl survey have been declining since the recent peak in 2020. They are now below their series mean. The longline (summer) and gillnet indices of the sentinel surveys were below their respective series mean in 2022. In 2022, cod condition was particularly poor, especially in division 4S, and at levels where increased natural mortality has been observed in the past. A new model was developed during the review of the northern Gulf of St. Lawrence cod assessment framework that took place in 2021 and 2022. This new model was used for the first time during the current assessment. Fishing mortality, for which the estimate is based on reported or inferred catches, was low in 2021 and even lower in 2022, specifically at the lowest level since the 2003 moratorium. However, natural mortality has been at high levels for at least a decade. It is likely that part of this natural mortality is in fact made up of unaccounted fishing mortality. A precautionary approach limit reference point (LRP), based on long-term stock trends in stock spawning biomass (SSB), was adopted at a value of 71,970 t. Other reference points using the same framework as the LRP have been proposed, including the upper stock reference point (USR, 143,939 t), the target reference point (TRP, 179,924 t), and the removal reference (Flim, 0.49). Given the high natural mortality, a limit reference point on total mortality should be considered. For 30 years, SSB has been at low levels. The SSB estimate for 2022 (42,906 t) was in the critical zone and corresponded to 60% of the LRP. Three-year SSB projections with recorded catch scenarios from 0 to 1,500 t were made. With these scenarios, the probability that the SSB increased went from 0.51 to 0.45. The high rate of natural mortality explained these modest prospects, which were projected despite significant recruitment to the adult biomass of the strong 2018 cohort. An examination of stock productivity revealed that the stock had surplus production for the majority of years since 1995 and would likely have grown in the absence of commercial and recreational fisheries.