Abstract
PandSKND, a subgroup of the NAFO/ICES Pandalus Assessment Group (NIPAG), met 20–21 February 20209 at ICES HQ in Copenhagen to assess the Pandalus stock in divisions 3a and 4a east. Experts attended from Norway, Sweden and Denmark (Chair: Ole Ritzau Eigaard, Denmark) and the objective was to assess stock status and to draft advice according to the current EU and Norway Long-term Management Strategy (LTMS). The LTMS requires ICES to provide both an update in-year TAC advice for 2020 and an initial TAC advice for the first two quarters of 2021.
The length-based Stock Synthesis (SS3) statistical framework was used to assess status of the stock based on updated input data (commercial catches for 2019 and survey catches from January 2020). The assessment demonstrated that the spawning–stock biomass (SSB) declined after 2008 and has fluctuated at a lower level since then. SSB in 2020 is between MSY-Btrigger and Blim. Fishing mortality (F) has been above FMSY in all years since 2011, except in 2015, 2018 and 2019. Recruitment has been below average since 2008, except for the 2013 year class.
In accordance with the LTMS reference points and Harvest Control Rules, ICES advises that catches in 2020 should be no more than 8736 tonnes and that catches for the first two quarters of 2021 should be no more than 4552 tonnes. This corresponds to a 31% reduction of the initial catch advice for 2020 and a 0.2% increase for the 2021 catch advice. The main reason for this change is that the realized 2019 catches were 29% higher than advised catches (7944 t compared to 6163 t) due to banking from 2018 (768 t), discarding (368 t), lack of correction for the loss in weight due to on-board boiling (approximately 463 t) and catching more than the TAC (approximately 180 t).
SS3 model diagnostics of the assessment did not indicate any issues with the model fit. There is a positive retrospective bias in SSB and recruitment, and a negative retrospective bias in F, but these are all within the acceptable range (Mohns Rho threshold values) of requiring no action.
The length-based Stock Synthesis (SS3) statistical framework was used to assess status of the stock based on updated input data (commercial catches for 2019 and survey catches from January 2020). The assessment demonstrated that the spawning–stock biomass (SSB) declined after 2008 and has fluctuated at a lower level since then. SSB in 2020 is between MSY-Btrigger and Blim. Fishing mortality (F) has been above FMSY in all years since 2011, except in 2015, 2018 and 2019. Recruitment has been below average since 2008, except for the 2013 year class.
In accordance with the LTMS reference points and Harvest Control Rules, ICES advises that catches in 2020 should be no more than 8736 tonnes and that catches for the first two quarters of 2021 should be no more than 4552 tonnes. This corresponds to a 31% reduction of the initial catch advice for 2020 and a 0.2% increase for the 2021 catch advice. The main reason for this change is that the realized 2019 catches were 29% higher than advised catches (7944 t compared to 6163 t) due to banking from 2018 (768 t), discarding (368 t), lack of correction for the loss in weight due to on-board boiling (approximately 463 t) and catching more than the TAC (approximately 180 t).
SS3 model diagnostics of the assessment did not indicate any issues with the model fit. There is a positive retrospective bias in SSB and recruitment, and a negative retrospective bias in F, but these are all within the acceptable range (Mohns Rho threshold values) of requiring no action.
| Original language | English |
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| Publisher | International Council for the Exploration of the Sea (ICES) |
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| Number of pages | 28 |
| Publication status | Published - 2020 |
| Series | ICES Scientific Report |
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| Number | 19 |
| Volume | 2 |
| ISSN | 2618-1371 |