Advice and Scenarios Database



Spurdog (Squalus acanthias) in subareas 1-10, 12 and 14 (the Northeast Atlantic and adjacent waters)
StockCode
dgs.27.nea
Assessment Year
2020
Stock Category
1
Purpose
Advice
Published
Stock Assessment Key
13967
Link to Advice Sheet
https://doi.org/10.17895/ices.advice.5820






Catch scenarios


Basis
Catch
Catch
Harvest rate
Harvest rate
Btot
Btot
% Btot change rel. to 2021
% Btot change rel. to 2021
% advice change
% advice change
2021 2022 2021 2022 2022 2023 2022 2023 2022 2023
(t) (t) (ratio) (ratio) (t) (t) (%) (%) (%) (%)
ICES Basis Advice
Zero catch 0 0 0 0 461188 474888 3 6.1 -100 -100
Other scenarios
Average catch 2007–2009 =2468 2468 2468 0.0076 0.0075 458701 469925 2.5 5 0 0
Harvest rate = HRMSY × Btot(2021 or 2022) /MSYBtrigger 7264 7430 0.022 0.023 453868 460111 1.37 2.8 194 201
TAC 2009=1422 1422 1422 0.0044 0.0043 459755 472029 2.7 5.4 -42 -42
Harvest rate = HRMSY (0.033) 10985 10963 0.034 0.034 450117 452813 0.54 1.14 345 344
SSB2022 = MSYBtrigger^




Symbol Footnotes
* Total biomass for 2022 or 2023 relative to the total biomass for 2021.
** Catch for 2020 or 2021 relative to the advice value for 2019 and 2020 (2468 tonnes).
*** The harvest rate shown is a weighted average (weighted by population number-at-age) for ages 5–30; therefore, there is a slight difference between the resultant harvest rate for ages 5–30 and HRMSY because of the slightly different age structure compared to equilibrium conditions.
^ The MSY Btrigger option was left blank because MSY Btrigger cannot be achieved in 2022, even with zero catch.