Joint NAFO/ICES Pandalus Assessment Working Group (NIPAG)

The NAFO/ICES Pandalus Assessment Group (NIPAG) met to assess the Pandalus stock in divisions 3.a and 4.a east. The objective was to assess stock status and to draft advice according to the EU and Norway Long-Term Management Strategy (LTMS). The LTMS requires ICES to provide an annual TAC advice according to a TAC-year from 1 July to 30 June.

A length and age-based Stock Synthesis (SS3) statistical framework was used to assess the status of the stock based on updated input data. The assessment model was revised during the 2022 benchmark (WKPRAWN 2022) and new reference points were calculated at the LTMS evaluation in 2023 (WKPANDLTMS 2023). The assessment model contains hermaphroditic parameters, two areas, and six fleets. The model is also fit using a novel ensemble approach whereby three different age-varying natural mortality rates are considered. The assessment demonstrated that the fishing pressure on the stock is below Ftarget and Fpa and that spawning–stock size is below MSY Btrigger and above Blim.

In accordance with the new LTMS and new reference points ICES advises that catches in the advice year 2024 should be no more than 4557 tonnes. This corresponds to an 11% reduction compared to the catch advice for assessment year 2023 (5125 tonnes). The further decrease in catch advice is linked to low recruitment, in particular the historically low recruitment of 2022, which has resulted in a relatively poor outlook for the stock. As a short-lived species, the stock dynamics are driven by year class variation and a recent increase in spawning stock biomass (SSB) was mainly the result of a single strong cohort (born in 2020) that will soon reach the end of its life. Total biomass estimated from survey data as well as commercial LPUE indices also confirm a downward trend in stock biomass in the beginning of 2024 after increases over the two preceding years. A further reduction in fishing mortality is therefore required to enable a rebuilding of the stock to target biomass levels.

SS3 model diagnostics of the assessment did not indicate any major issues with model fit; the model passed >80% of the model diagnostics considered. There is minimal retrospective bias in terms of SSB and F. There is a high MASE hindcasting score for the survey in both 3.a and 4.a east and further work will be needed to investigate this.