PLAICE
Pleuronectes platessa
Publication of Advice: 6 June 2025. Published by Marine and Freshwater Research Institute.
Advice
MFRI and ICES advise that when the Icelandic management plan is applied, catches in the fishing year 2025/2026 should be no more than 7 871 tonnes.
Stock development
Fishing pressure on the stock is below Fmsy, Fpa and Flim; spawning-stock is above MGT Btrigger , Bpa and Blim.
Plaice. Catch by gear type, recruitment (age 3), fishing mortality (ages 5–10), and spawning stock biomass (SSB). Shaded areas and error bars show 95% confidence intervals.
Basis of the assessment and reference points
Basis of the advice | Management plan |
Management plan | TAC set using the ICES advice rule with a fishing mortality FMGT =0.30 applied to ages 5–10, modified by the ratio SSBy/MGT Btrigger when SSBy < MGT Btrigger |
Assessment type | Statistical catch at age model (SAM) |
Input data | Catch in numbers and age disaggregated survey indices (IS-SMB) |
Approach | Reference point | Value | Basis |
|---|---|---|---|
MSY approach | MSY Btrigger | 12 400 | Bpa |
FMSY | 0.41 | Leads to long-term MSY, based on stochastic simulations (EqSim) | |
Management plan | MGT Btrigger | 12 400 | Management plan |
FMGT | 0.3 | Management plan | |
Precautionary approach | Blim | 10 100 | Lowest SSB (1990) where large recruitment was observed |
Bpa | 12 400 | Blim x e1.645 * 0.12 | |
Flim | 0.57 | Fishing mortality that in stochastic equilibrium will result in median SSB at Blim |
Prospects
The Icelandic Ministry of Industries has a fisheries management plan for Icelandic plaice which was evaluated by ICES (ICES, 2022). It is considered to be precautionary and conforms to ICES MSY approach. According to the management plan, FY/Y+1, i.e. the advice fishing mortality that is applied from 1 September in year Y to 31 August in year Y+1, is calculated from the harvest control rule (HCR) as:
\[ \text{F}_{Y⁄Y+1}=\text{min}\left(\frac{\text{SSB}_Y}{\text{MGT B}_{trigger}} ,1\right) \text{F}_{MGT} \]
To calculate the catch in the last four months of the year Y (September through December), the following F is used in the year Y:
\[ \text{F}_Y=\frac{2}{3}\text{F}_{SQ} + \frac{1}{3}\text{F}_{MGT} \]
In year Y+1, F(Y⁄Y+1) is used. Finally, the catch advice for the year Y/Y+1 is calculated using the following formula:
\[ C_{Y⁄Y+1}=\frac{1}{3}C[\text{F}_Y]+ \frac{2}{3} C[\text{F}_{Y/Y+1}] \]
where the catch C[.] is calculated using the Baranov catch equation with the corresponding biomass, natural mortality, and fishing mortality values in each year.
Plaice. Assumptions made for the interim year and in the forecast.
Variable | Value | Notes |
|---|---|---|
Catch (2025) | 7 105 | Results from Fages–5-10 (2025); in tonnes. |
SSB (2026) | 19 743 | Short-term forecast; in tonnes |
Recruitment age 3 (2026) | 16 586 | Estimated by the model; in thousands |
Recruitment age 3 (2027) | 16 586 | Average of the past 10 years of the assessment; in thousands |
Fages5-10 (2025) | 0.27 | Assuming status quo F (average over the last three years) for 1 January–31 August 2025 and FMGT for 1 September–31 December 2025; tonnes |
Plaice. Projection of SSB based on catch according to the management plan. All weights are in tonnes.
Basis | Catch (2025/2026) | Fishing mortality (2025/2026) | SSB (2027) | % SSB change1) | % advice change2) |
|---|---|---|---|---|---|
Management plan | 7 871 | 0.3 | 18 906 | -4 | 0 |
1) SSB in 2027 relative to SSB in 2026 | |||||
2) Advice value for 2025/2026 relative to advice value for 2024/2025 (7878 t) | |||||
Quality of the assessment
The assessment is consistent with the previous assessments.
Plaice Current assessment (red line) compared with previous estimates (2022–2024).
Other information
The MFRI recommends that regulations regarding area closures on spawning grounds remain in effect.
Advice, TAC and Catch
Plaice. Recommended TAC, national TAC, and catches (tonnes).
Fishing year | Recommended TAC | National TAC | Total catch |
|---|---|---|---|
1991/1992 | 10 000 | 11 000 | 10 175 |
1992/1993 | 10 000 | 13 000 | 15 474 |
1993/1994 | 10 000 | 13 000 | 12 465 |
1994/1995 | 10 000 | 13 000 | 11 320 |
1995/1996 | 10 000 | 13 000 | 11 197 |
1996/1997 | 10 000 | 12 000 | 10 516 |
1997/1998 | 9 000 | 9 000 | 8 241 |
1998/1999 | 7 000 | 7 000 | 7 711 |
1999/2000 | 4 000 | 4 000 | 4 975 |
2000/2001 | 4 000 | 4 000 | 4 946 |
2001/2002 | 4 000 | 5 000 | 4 420 |
2002/2003 | 4 000 | 5 000 | 5 427 |
2003/2004 | 4 000 | 4 500 | 5 861 |
2004/2005 | 4 000 | 5 000 | 6 193 |
2005/2006 | 4 000 | 5 000 | 5 659 |
2006/2007 | 5 000 | 6 000 | 6 144 |
2007/2008 | 5 000 | 6 500 | 6 624 |
2008/2009 | 5 000 | 6 500 | 6 368 |
2009/2010 | 5 000 | 6 500 | 6 389 |
2010/2011 | 6 500 | 6 500 | 4 846 |
2011/2012 | 6 500 | 6 500 | 5 819 |
2012/2013 | 6 500 | 6 500 | 5 935 |
2013/2014 | 6 500 | 6 500 | 6 036 |
2014/2015 | 7 000 | 7 000 | 6 230 |
2015/2016 | 6 500 | 6 500 | 7 612 |
2016/2017 | 7 330 | 7 330 | 6 373 |
2017/2018 | 7 103 | 7 103 | 8 208 |
2018/2019 | 7 132 | 7 132 | 7 096 |
2019/2020 | 6 985 | 6 985 | 7 177 |
2020/2021 | 7 037 | 7 037 | 9 082 |
2021/2022 | 7 805 | 7 805 | 7 306 |
2022/2023 | 7 663 | 7 663 | 7 329 |
2023/2024 | 7 830 | 7 830 | 7 109 |
2024/2025 | 7 878 | 7 878 | |
2025/2026 | 7 871 |
References and further reading
ICES. 2022a. Workshop on the evaluation of assessments and management plans for ling, tusk, plaice and Atlantic wolffish in Icelandic waters (WKICEMP). ICES Scientific Reports. 4:37. 271 pp. https://doi.org/10.17895/ices.pub.19663971
ICES. 2022b. Advice on fishing opportunities. In Report of the ICES Advisory Committee, 2022. ICES Advice 2022, section 1.1.1. https://doi.org/10.17895/ices.advice.19928060
MFRI Assessment Reports 2025. Plaice. Marine and Freshwater Research Institute, 6 June 2025.