Ref. Ares(2018)3458435 - 29/06/2018
Ref. Ares(2019)2387732 - 04/04/2019
High survival exemption for plaice caught by TR2 vessels
using Trammel Nets in ICES areas VIId and VIIe
Request under Article 15.4(b) of Regulation (EU) 1380/2013 to exempt from the landing
obligation plaice caught by trammel nets in ICES areas VIId and VIIe.
Summary
Article 15.4(b) of Regulation (EU) 1380/2013 on the Common Fisheries Policy states that
the landing obligation shall not apply to:
“species for which scientific evidence demonstrates high survival rates, taking into
account the characteristics of the gear, of the fishing practises and of the
ecosystem;”
In response to industry’s view that Plaice has a high rate of survival, the Centre for
Environment, Fisheries and Aquaculture Science (Cefas) was commissioned to carry out a
number studies on high survivability of Plaice. This study was undertaken by Cefas in the
Eastern Channel trammel net fishery
The North Western Waters regional group notes that scientific evidence demonstrates a
survivability rate of 73% for plaice (Pleuronectes platessa) caught by TR2 vessels using
trammel nets in area VIIe and recommends that catches of Plaice caught in areas VIId and
VIIe should be exempt from the landing obligation on grounds of high survival rates, as
provided for by Article 15.4(b) Regulation (EU) 1380/2013. This will reduce the risk of
vessels being prevented from continuing to fish at sea due to their low Plaice quota.
Key Information
Exemption target: Plaice (Pleuronectes platessa)
Exemption grounds:
High survivability.
Survivability rates:
73%
Vessels affected:
87
Discard rate:
32%
2018 UK TAC:
3,014
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Fishery
In 2017, 87 vessels registered in the UK caught plaice with Trammel Nets in area VIId and
VIIe, with a total catch of 62 tonnes. The discard rate for the stock in area VIId and VIIe is
currently at 32%. An estimated 19.8 tonnes will be discarded in 2018. The survival rate in
the study is 64%, which would indicate that around 14.3 tonnes of the discarded Plaice will
survive.
Study
The vessel used in this study was 9.8m in length, with a width of 3.8m, a draught of 1.8m
and powered by a 147 horsepower diesel engine. The vessel operated out of Sovereign
Harbour, near Eastbourne, fishing the Eastern Channel (see Figure 1). Plaice are caught
as a bycatch species, mostly during targeted sole fishing.
For this study fishing took place in the Pevensey Bay area of ICES Division VIId, with a
fishing day lasting about 8 hours.
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Figure 1. The locations of the hauls observed in this study (Case 4) on plaice high survival in
trammel nets.
Data collection
All plaice caught were recorded by length. Each individual fish was measured and scored
using a predefined assessment protocol developed methods described in the ICES
WKMEDS 2014 report and refined in the Cefas laboratory using aquarium kept plaice.
Vitality was assess using a semi-quantitative assessment of activity and a quantitative
reflex and injury scoring method.
Vitality assessment
A total of 1004 plaice were caught. Fish were held in captivity for 168-342h. Table 1 sets
out the vitality assessment of the plaice catch, and its relevant high survival probability.
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Table 1: Survivability and catch profile of study by vitality assessment for plaice.
Proportion of fish at each
Survivability probability
Vitality assessment
vitality
(%)
Excellent
0.68
80.3
Good
0.29
71
Poor
0.10
-
Moribund
0.20
-
N.B. No plaice were categorised as Dead. Insufficient catches of Poor and Moribund plaice to
investigate high survivability.
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Figure 2. Length frequencies of plaice in trammel net catches and held for observation
Results
From the extension models used in the study, because the rate of mortality had reduced
within the observation time, the forecast survival estimate was comparable at 71.1-71.9%
The study identified a number of potential stressors on the captive fish associated with the
methodology in this study, which are likely to have resulted in experimental induced
mortality and therefore underestimated survival. Specifically these stressors included:
Handling fish to conduct the vitality assessments, length measurements and to put
fish into the on-board tanks
Captivity in the on-board tanks (movement caused by vessel movement; proximity
with other fish; serial flow of water from top to bottom tank)
Stopping water flow to on-board tanks on approach to port until docked (reducing
dO2)
Transfer of fish into tubs (handling of fish)
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Carrying tubs off the vessel and transporting, by van, to onshore holding tanks
(increased temperature, reduced dO2, movement)
Handling the fish to transfer into onshore tanks
Adjusting to salinity and temperature
Monitoring captive fish using tail grab
Conclusion
The UK believes that the fishing practices in this study resulting in survival rates of 72% for
bycatches of Plaice are representative of general fishing practices by the vessels using
trammel nets in ICES areas VIId & VIIe.
On this basis we would like to request a high survival exemption for plaice caught by
trammel nets in ICES Areas VIId & VIIe.
Further information on this study can be found in Annex A under case study 4
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Table 5: Completed STECF table for high survivability proposal
Country
Exemption
Species as
Number of
Landings (by Estimated
Estimated
Discard Rate Estimated
applied for
bycatch or
vessels
landing
Discards
Catch
discard
(species, area,
target
subject to
obligation
survival rate
gear type)
the landing
subject
from
obligation
vessels)
provided
studies
UK
Plaice
By catch
87
62t
33.3t
104.16t
32%
73%
Area VIId and
VIIe
TR2 vessels
using Trammel
nets
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Document Outline