Advice and Scenarios Database



Mackerel (Scomber scombrus) in subareas 1-8 and 14 and Division 9.a (the Northeast Atlantic and adjacent waters)
StockCode (Assessment Component)
mac.27.nea
Assessment Year
2026
Stock Category
1
Purpose
Advice
Published
Stock Assessment Key
25875
Link to Advice Sheet
https://doi.org/10.17895/ices.advice.30932144






Catch scenarios


Basis
Total catch
Fages 4–8
Fages 4–8
Spawning-stock biomass (SSB) at spawning time
Spawning-stock biomass (SSB) at spawning time
Change in SSB
Change in ctach
Change in advice
Probability of SSB below Blim
2027 2027 2028 2027 2028 2028 2027 2027 2028
(t) (ratio) (ratio) (t) (t) (%) (%) (%) (%)
ICES Basis Advice
Maximum sustainable yield (MSY) approach: F2027 = FMSY* SSB2026/MSY Btrigger 352938 0.149 0.149 3135352 3345872 6.71 -11.36 102.42 33.2
Other scenarios
F=FMSY=FPA 443198 0.191 0.191 3118364 3269935 4.86 11.3 154.19 37.6
F = 0 0 0 0 3196892 3652549 14.25 -100 -100 16.9
Catch2027 = Catch2026 398187 0.169 0.169 3127653 3307790 5.76 0 128.37 35.6
Catch2027 = Catch2026 +25% 497733 0.217 0.217 3108611 3223577 3.7 25 185.47 40.7
Catch2027 = Catch2026 -20% 318549 0.132 0.132 3142315 3374873 7.4 -20 82.7 31.6
F = F2026 392517 0.167 0.167 3127869 3312345 5.9 -1.42 125.12 35.1
SSB2028 = Blim^^ 675632 0.309 0.309 3069021 3068002 -0.03 69.68 287.5 50
SSB2028 = BPA^^
p(SSB2028<;Blim) = 5%^^
Technical service scenarios#
HCRa##; all Fmin options 352938 0.149 0.149 3135352 3345872 6.71 -11.36 102.42 33.2
HCRb; Fmin=0### 63697 0.0249 0.0249 3186439 3596764 12.88 -84 -63.47 19.4
HCRb; Fmin=0.025 63811 0.025 0.025 3186421 3596663 12.87 -83.97 -63.4 19.4
HCRb; Fmin=0.05 125744 0.05 0.05 3175869 3542169 11.53 -68.42 -27.88 22.3
HCRb; Fmin=0.075 185862 0.075 0.075 3165413 3489351 10.23 -53.32 6.6 25
HCRb; Fmin=0.1 244227 0.1 0.1 3155358 3438653 8.98 -38.67 40.07 27.7




Symbol Footnotes
* SSB2028 relative to SSB2027.
** Catch in 2027 relative to forecasted catches in 2026 (398 186 tonnes). There is no internationally agreed total allowable catch (TAC) for 2026.
*** Advice value for 2027 relative to the advice value for 2026 (174 357 tonnes).
# HCRa and HCRb correspond to the harvest control rules (HCRs) tested in the technical service regarding the impacts of different HCRs for Atlantic mackerel (ICES, 2026a). Both HCRs apply a fishing mortality equal to FMSY when the SSB in the current year is equal to or above MSY Btrigger. Below MSY Btrigger the rules apply a linear decline of F towards F=0 at SSB=0 for HCRa and towards F=0 for SSB=Blim for HCRb until a minimum level of fishing mortality (Fmin).
## For all stock sizes above Blim, HCRa gives the same advice as the ICES HCR rule.
### SSB at the beginning of the advice year is above Blim, therefore the advised fishing mortality for this HCR is positive and by chance is very close to the Fmin = 0.025.
^ The probability of SSB being below Blim in 2028. This probability relates to the short-term probability of SSB below Blim and is not comparable to the long-term probability of SSB below Blim tested in simulations when estimating fishing mortality reference points.
^^ The SSB value differs slightly from Blim because the forecast is constrained by fishing mortality, and this is the closest value to Blim that could be achieved.
^^^ These options cannot be achieved even with zero catch in 2027.