Advice and Scenarios Database



Herring (Clupea harengus) in Division 7.a North of 52°30’N (Irish Sea)
StockCode (Assessment Component)
her.27.nirs
Assessment Year
2025
Stock Category
1
Purpose
Advice
Published
Stock Assessment Key
19783
Link to Advice Sheet
https://doi.org/10.17895/ices.advice.27202641.v1






Catch scenarios


Basis
Total catch (2026)
F2-4(2026)
Spawning stock biomass (SSB*; 2026)
SSB*, ^ (2027)
% SSB change**
% advice change^^
Probability SSB <; Blim in 2026 (%)***
2026 2026 2026 2027 2026 2026 2026
(t) (ratio) (t) (t) (%) (%) (%)
ICES Basis Advice
MSY approach: FMSY × (SSB2025)/MSY Btrigger) 2935 0.198 11160 12745 19.3 -8.5 8.5
Other scenarios
F=0 0 0 13333 17286 42.5 -100 1.2
F = Fpa = FMSY 3605 0.25 10672 11750 14 12.4 11.6
F=Fsq 5271 0.389 9512 9636 1.65 64 22
SSB (2026)=Blim 8335 0.702 7352 6433 -21 160 50
SSB (2026)=Bpa= MSYBtrigger 2125 0.14 11793 13900 26 -34 5
MSY approach:FMSY × (SSB2025)/MSY Btrigger) with intermediate year catch of 3 206 t ^^^ 3767 0.23 11981 12794 10.2 17.5 4.3




Symbol Footnotes
* For autumn-spawning stocks, the spawning stock biomass (SSB) is determined at spawning time and is influenced by fisheries between 01January and spawning (set for September).
** SSB 2026 relative to SSB 2025 (9 358t).
*** The probability of SSB being below Blim in 2026. This probability relates to the short-term probability of SSB <; Blim and is not comparable to the long-term probability of SSB <; Blim tested in simulations when estimating fishing mortality reference points.
^ Assuming same fishing mortality in 2027 as in 2026.
^^ Advice value for 2026 relative to the advice value for 2025 (3 206 tonnes).
^^^ Additional scenario following MSY approach with an intermediate assumption of catches matching reissued ICES catch advice for 2025 of 3 206 t, resulting in F of 0.220 and SSB 10 868 t in 2025 for this scenario. Recruitment assumption is unchanged.