Advice and Scenarios Database



Witch (Glyptocephalus cynoglossus) in Subarea 4 and divisions 3.a and 7.d (North Sea, Skagerrak and Kattegat, eastern English Channel)
StockCode
wit.27.3a47d
Assessment Year
2022
Stock Category
1
Purpose
Replaced
Published
Stock Assessment Key
17059
Link to Advice Sheet
https://doi.org/10.17895/ices.advice.19458614.v1






Catch scenarios


Basis
Total catch^^
Projected landings
Projected discards*
Ftotal ages 4–8
SSB^
SSB^
% SSB change**
% advice change***
2023 2023 2023 2023 2024 2023 2024 2024 2024
(t) (t) (t) (ratio) (t) (t) (%) (%)
ICES Basis Advice
MSY approach: FMSY × SSB(2022)/MSY Btrigger 1313 1215 98 0.12 4543 5948 28 8.9
Other scenarios
FMSYlower × SSB(2022)/MSY Btrigger 954 882 72 0.09 4620 6218 30 -21
F=0 0 0 0 0 4814 6942 36 -100
Fpa 2871 2644 227 0.28 4206 4848 18.7 138
Flim 3228 2968 260 0.32 4132 4612 16.6 168
Fsq 2961 2726 235 0.29 4187 4788 18.1 146
SSB (2024)=Blim 5916 5379 537 0.68 3505 3077 -1.1 390
SSB (2024)=Bpa 3595 3307 288 0.36 4051 4381 14.3 198
SSB (2024)=MSYBtrigger 3595 3307 288 0.36 4051 4381 14.3 198
Rollover advice 1206 1115 91 0.11 4567 6124 29 0
FMSY 1601 1483 118 0.15 4482 5732 26 33
FMSY lower 1168 1080 88 0.11 4575 6054 29 -3.2




Symbol Footnotes
* Including BMS landings, assuming recent discard rate (average of 2019–2021).
** SSB in 2023 relative to SSB in 2022 (3544 tonnes).
*** Advice value for 2023 relative to advice value for 2022 (1206 tonnes).
^ SSB is estimated at spawning time (1 July).
^^ Other scenarios do not include FMSY upper because SSB (2022) less MSY Btrigger.