Advice and Scenarios Database



Four-spot megrim (Lepidorhombus boscii) in divisions 8.c and 9.a (southern Bay of Biscay and Atlantic Iberian waters East)
StockCode
ldb.27.8c9a
Assessment Year
2018
Stock Category
1
Purpose
Advice
Published
Stock Assessment Key
9788
Link to Advice Sheet
https://doi.org/10.17895/ices.pub.4465






Catch scenarios


Basis
Total catch
Wanted catch
Unwanted catch
Ftotal
Flandings
Fdiscards
SSB
% SSB change*
% Advice change**
2019 2019 2019 2019 2019 2019 2020 2020 2020
(t) (t) (t) (ratio) (ratio) (ratio) (t) (%) (%)
ICES Basis Advice
MSY approach: FMSY 1633 1270 363 0.193 0.104 0.089 9286 5.1 16.7
Other scenarios
F = 0 0 0 0 0 0 0 11219 27 -100
Fpa 3079 2369 710 0.41 0.22 0.19 7581 -14.2 120
Flim 3963 3028 935 0.57 0.31 0.26 6543 -26 183
SSB (2020) = Blim 6685 5108 1577 0.96 0.52 0.44 3330 -62 378
SSB (2020) = Bpa 5610 4286 1323 0.81 0.43 0.37 4600 -48 301
SSB (2020) = MSYBtrigger 5610 4286 1323 0.81 0.43 0.37 4600 -48 301
F = F2018 2245 1739 506 0.28 0.15 0.129 8564 -3.1 60
FMSY lower 1101 860 241 0.125 0.067 0.058 9916 12.2 -21
FMSY upper (without advice rule) 2325 1800 525 0.29 0.156 0.134 8469 -4.2 66
F multiplier for FMSY of L.whiffiagonis = F2018× 0.649^ 1539 1198 341 0.181 0.097 0.084 9398 6.4 10




Symbol Footnotes
* SSB 2020 relative to SSB 2019.
** Catch advice value for 2019 relative to catch advice value for 2018 (1399 tonnes).
^ This catch option applies the same multiplicative factor to the current fishing mortality (F2018) for both megrim species (L.whiffiagonis and L.boscii). This year the L.whiffiagonis multiplier is used.