Advice and Scenarios Database



Plaice (Pleuronectes platessa) in Subarea 4 (North Sea) and Subdivision 20 (Skagerrak)
StockCode
ple.27.420
Assessment Year
2018
Stock Category
1
Purpose
Advice
Published
Stock Assessment Key
10222
Link to Advice Sheet
https://doi.org/10.17895/ices.pub.4613






Catch scenarios


Basis
Total catch
Wanted catch*
Unwanted catch*
^^ Ftotal ages 2–6
Fwanted ages 2–6
Funwanted ages 2–3
SSB
% SSB change**
% TAC change***
% Advice change^
2019 2019 2019 2019 2019 2019 2020 2020 2020 2020
(t) (t) (t) (ratio) (ratio) (ratio) (t) (%) (%) (%)
ICES Basis Advice
MSY approach: FMSY 142217 92764 49453 0.21 0.1 0.195 1032942 5.1 11.1 -0.185
Other scenarios
F = MAP FMSY upper 196026 128345 67681 0.3 0.143 0.28 980393 0 53 38
F = MAP FMSY lower 101322 65915 35407 0.146 0.069 0.135 1073066 9.2 -21 -29
F = 0 0 0 0 0 0 0 1174144 19.4 -100 -100
Fpa 234569 154023 80546 0.37 0.175 0.34 942939 -4.1 83 65
Flim 309609 204534 105075 0.52 0.25 0.48 870509 -11.2 142 117
SSB (2020) = Blim 1070822 803306 267516 6 2.8 5.5 207288 -79 740 650
SSB (2020) = Bpa 962080 702268 259812 4 1.91 3.7 290203 -70 650 580
SSB (2020) = MSYBtrigger 637266 436555 200711 1.48 0.71 1.38 564599 -43 400 350
Rollover TAC 127986 83139 44847 0.187 0.089 0.173 1047281 7.1 0 -10.2
F2019 = F2018 135349 88244 47105 0.199 0.095 0.185 1039670 6.1 5.8 -5
A: Max. 196359 0.32 930211 -6 53 38
B: Min. 52437 0.077 1070855 9 -59 -63
C: COD 80026 0.12 1043736 6 -37 -44
D: SQ effort 121218 0.187 1003379 2 -5 -14
E: Value 126469 0.196 998247 2 -1 -11
F: Range 112778 0.162 1062841 8 -11 -21




Symbol Footnotes
* “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 2015–2017. Both wanted and unwanted catch refer to Subarea 4 and Subdivision 20, calculated as the projected total stock wanted catch (including Division 7.d) deducted by the catch of plaice from Subarea 4 taken in Division 7.d in 2019. The subtracted value (649 t of wanted catch and 398 t of unwanted catch) is estimated based on the plaice catch advice for Division 7.d for 2019.
** SSB 2020 relative to SSB 2019.
*** Total catch in 2019 relative to the combined TAC of Subarea 4 and Subdivision 20 in 2018 (127 986 t).
^ Total catch in 2019 relative to advice value 2018 (142 481 t).
^^ Fwanted and Funwanted do not sum up to the Ftotal as they are calculated using different ages.
A. Maximum scenario: Each fleet stops fishing when its last stock share is exhausted.
B. Minimum scenario: Each fleet stops fishing when its first stock share is exhausted.
C. COD: Each fleet stops fishing when its individual cod share is exhausted.
D. SQ (status quo) effort scenario: The effort of each fleet in 2017 and 2018 is as in 2016.
E. Value scenario: The effort of each fleet is equal to the weighted average of the efforts required to catch the fleet’s quota share of each of the stocks, where the weights are the relative catch values of each stock in the fleet’s portfolio.
F. Range scenario: The potential for TAC mismatches in 2018 are minimized within the FMSY range, for the demersal fish stocks for which such a range is available (cod.27.47d20; had.27.46a20; pok.27.3a46; ple.27.420; ple.27.7d; sol.27.4; sol.27.7d).