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
2023
Stock Category
1
Purpose
Advice
Published
Stock Assessment Key
17855
Link to Advice Sheet
https://doi.org/10.17895/ices.advice.21864345.v1






Catch scenarios


Basis
Total catch
Projected landings
Projected discards *
Ftotal (ages 4-8)
SSB^
SSB ^€
% SSB change **
% advice change ***
2024 2024 2024 2024 2024 2025 2024 2024
(t) (t) (t) (ratio) (t) (t) (%) (%)
ICES Basis Advice
MSY approach: FMSY × SSB(2023)/MSY Btrigger 1579 1474 105 0.144 4987 5911 23 32
Other scenarios
FMSYlower × SSB(2023)/MSY Btrigger 1098 1027 71 0.098 5106 6314 26 -8.3
F=0 0 0 0 0 5355 7244 32 -100
Fpa 2764 2573 191 0.267 4699 5044 16 131
Flim 3331 3091 240 0.331 4557 4650 12.5 177
F = F2023 2588 2413 175 0.25 4740 5159 17 116
SSB (2025) = Blim 5556 5119 437 0.63 3973 3293 -1.9 360
SSB (2025) = Bpa= MSY Btrigger 3443 3191 252 0.34 4525 4576 11.7 187
Rollover advice 1198 1120 78 0.108 5082 6332 25 0
FMSY 1770 1650 120 0.163 4941 5769 22 48
FMSY lower 1233 1153 80 0.111 5073 6198 25 2.9




Symbol Footnotes
* Including BMS landings. Assuming recent discard rate (average of 2020–2022).
** SSB in 2024 relative to SSB in 2023 (4050 tonnes).
*** Advice value for 2024 relative to advice value for 2023 (1198 tonnes).
^ SSB is estimated at spawning time (1 July).
€ Assuming same Ftotal (ages 4-8) in 2025 as in 2024.