Advice and Scenarios Database



Turbot (Scophthalmus maximus) in Subarea 4 (North Sea)
StockCode
tur.27.4
Assessment Year
2019
Stock Category
1
Purpose
Advice
Published
Stock Assessment Key
11537
Link to Advice Sheet
https://doi.org/10.17895/ices.advice.4876






Catch scenarios


Basis
Total catch*
Wanted catch**
Unwanted catch**
F (wanted catches, ages 2–6)
SSB
% SSB change ***
% Advice change ^
2020 2020 2020 2020 2021 2021 2021
(t) (t) (t) (ratio) (t) (%) (%)
ICES Basis Advice
Precautionary approach: Fpa 4538 3902 635 0.47 7753 -9.4 -8.4
Other scenarios
MSY approach: FMSY 3649 3138 511 0.36 8575 0.185 -26
FMSY upper= 0.48 4614 3968 646 0.48 7683 -10.2 -6.8
FMSY lower= 0.25 2664 2291 373 0.25 9495 10.9 -46
F = 0 0 0 0 0 12019 40 -100
Fpa 4538 3902 635 0.47 7753 -9.4 -8.4
Flim 5545 4768 777 0.61 6830 -20 12
Fsq 3617 3111 507 0.36 8605 0.53 -27
SSB (2021) = Blim 9945 8552 1393 1.58 2974 -65 101
SSB (2021) = Bpa 8542 7346 1196 1.18 4163 -51 73
SSB (2021) = MSYBtrigger 6071 5220 850 0.69 6353 -26 23
Roll-over advice 4952 4258 694 0.53 7372 -13.9 0




Symbol Footnotes
* (Wanted catch) / (1 – average discard rate); average discard rate 2016–2018 = 14.0%.
** “Wanted” and “unwanted” catch are used to describe fish that would be landed and discarded in the absence of the EU landing obligation, based on average discard rate estimates for 2016–2018 (14.0%); unwanted catch = (wanted catch) × (average discard rate) / (1 – average discard rate).
*** SSB 2021 relative to SSB 2020.
^ Total catch in 2020 relative to advice value for 2018 and 2019 (4952 tonnes).