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Major question marks of the CNPMEM concerning pulse gear

Governance, regionalisation and respect of the CFP: The start of the pilot project, without
taking into account the opinions of the relevant Advisory Councils, is a circumvention of
the article 14 of the new CFP.
Indeed, the article 14 of this policy, on which is based this study, imposes to take into
account the opinions of the North Sea Advisory Council. It is not the case while the
planning of the program of this study provides to start this point during the second quarter
2014.

Lack of transparency: from a general point of view, the way to develop this fishery technic
suffers a clear lack of transparency.
The way to develop this technic suffers a clear lack of transparency:
- In 2006, when the derogation of 5% of the beam trawl fleet was implemented;
- In 2011, when a bilateral agreement between the European Commission and the
Netherlands allowed 20 licences more for this country (not mentioned in the
document “Pulse trawl – Policy and dispensation”);
- In 2014, when the European Commission gave an agreement for 42 licences more
for Netherlands according to article 14 of the new CFP but without taking into
account the advice of the NSAC.

Justification of the size of the fleet: this pilot study doubles the number of licences for the
Dutch beam trawl fleet.
With 84 licences for the Dutch beam trawl fleet, this project doubles the number of licences.
The Dutch beam trawl fleet has 340 vessels in 2014. This number is calculated by summing
the number of vessels using the beam trawl as main gear (320 vessels) or as second gear
(20 vessels). These 84 licences represent 25% of this fleet. A pilot study allowing equipping
25 % of the fleet with a derogatory engine resembles to a roundabout method to develop a
new fishery or a reconversion of this fleet.

Link between the pilot study and the ICES: what is the link of this pilot study with the ICES?
During the last WGELECTRA (October 2014), it was noted that this pilot study and the
WGELCETRA is not strongly connected. Moreover, in 2012, France made a request to the
ICES to review the work of SGELECTRA and to provide and update advice on electric
pulse trawl. One of the conclusions was: “Consideration could be given to experimental
increases, beyond 5 % in the beam trawler fleet, in selected area to further investigate the
outstanding issues mentioned above”.
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
Management of the resource: the augmentation of the efficiency with the pulse trawl could
occur a significant impact on the stocks exploited in the south of the North Sea.
In the report of the ICES group SGELECTRA 2013, Bob van Marlen mentions that a rise
of near 450 % of the landings between the beginning and the end of the experiments lead
in 20111. For the shrimp fisheries, a rise of 50 % of the commercial catches was observed2.
We can fear a risk of over exploitation of these stocks, already limited within this area and
limited by quota.

Lack of clarity on the way to estimate the reduction of discards: the main results about the
reduction of discards come from two studies: a catch comparison between both pulse gears
and a traditional beam trawl executed in 2011 (van Marlen et al., 2014) and a pulse
monitoring program performed between December 2011 and March 2013 (Rasenberg et
al., 2013). But on the one hand we have a reduction of 43% of the discards (van Marlen et
al., 2014) and on the other hand we observe a similar catch composition between pulse
trawl and traditional beam trawl (Rasenberg et al., 2013). It seems there is confusion
between catch efficiency and catch composition.
A comparative fishing experiment was carried out with three Dutch vessels fished side-byside (two pulse trawls (TX36 and TX 68) and one traditional beam trawl (GO4)) for a week
in May 2011. One of the conclusions was a reduction of discards (43%) (van Marlen et al.,
2014).
Species
Plaice
Sole
Plaice
Sole
landings
Comparaison (kg/h)
TX36/GO4
70,8%
TX36/GO4
84,1%
TX68/GO4
72,2%
TX68/GO4
87,5%
discards
(kg/h)
46,4%
36%
57,3%
60,7%
Figure 1: Comparison of landings and discards of target species and sole raised to total trip
duration (B. van Marlen et al., 2011, IMARES report C122b/11).
But, results of the pulse monitoring program performed between December 2011 and
March 2013 (Rasenberg et al., 2013) show different results.
Type of fishery
1
Plaice
Sole
L
DC
%DC
L
DC
%DC
Pulse self sampling
37
27
42%
35
6
15%
Pulse observer
61
66
52%
32
4
10%
Beam trawl (DCF)
90
87
49%
29
6
17%
« Landings increased largely from 1000 to 3500-4000 kg per week when pulse trawling was started » (p.6
rapport CIEM SGELECTRA 2013)
2
« Logically no discard reduction was observed. However, commercial catch increase unexpectedly rode to
50%” (p.7 rapport CIEM SGELECTRA 2013)
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Figure 2: catch composition (Rasenberg et al., 2013).
In fact, we have a catch efficiency in the 2011 study and a catch comparison in the 2013
study. If we look closer the data of the 2011 study, we observe that the catch composition
for sole and plaice between the pulse gears and the traditional beam trawl is quite similar,
like in the 2013 study.
Vessels Species landings (kg/h)
discards (kg/h)
% discards
Plaice
34,9
106,8
Sole
17,6
2,8
Plaice
24,7
49,6
TX36
Sole
14,8
1
Plaice
25,2
61,2
TX68
Sole
15,4
1,7
Figure 3: Catch composition of the 2011 study (data from the
IMARES report C122b/11).
GO4
75%
14%
67%
6%
71%
10%
B. van Marlen et al., 2011,
So, it appears that the catch composition for sole and plaice is quite similar between pulse
gears and traditional beam trawl in both studies.
Plaice
Sole
van Marlen et
van Marlen et
Rasenberg et al., 2013
al., 2014
Rasenberg et al., 2013
al., 2014
Beam trawl (DCF) 49% GO4
75% Beam trawl (DCF)
17% GO4
14%
Pulse self sampling 42% TX36
67% Pulse self sampling
15% TX36
6%
Pulse observer
52% TX68
71% Pulse observer
10% TX68
10%
Figure 4: comparison of the catch composition of sole and plaice in the Rasenberg et al.,
2013 study and in the van Marlen et al., 2014 study.
In the 2011 study, we have a catch efficiency. But if we take into account that, as we say
previously, that “sole landings increased largely from 1000 to 3500-4000 kg per week when
pulse trawling was started”, and as the catch composition is quite similar for sole and plaice
between pulse gears and traditional gear, we don’t understand how the reduction of plaice
and sole discards (species under quota) is still so important with pulse gears in 2014. We
fear a management problem with increased efficiencies in fisheries.

Control and enforcement procedures: with varying pulse settings and electrode
arrangement we fear a management problem in this fishery. Guarantees should be given
that all the 82 fishing boat involved can be properly controlled.
Control of the pulse gear occurs, for now, on the basis of a technical dossier and physical
controls. A black box system will be improved. So, for now, in case of doubt, it is not
possible for control agencies to do measurements needed in order to check it with the
technical files. We don’t understand why it is needed to have 42 more vessels in order to
implement this black box.
Moreover, in 2012, STECF recommended that the control and enforcement issues were
resolved before the proportion of the beam trawl fleet using pulse trawls is increased.
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
Undervalued impacts of the pulse beam trawl on cod catches: The study of IMARES 2011
underestimates the damage on cod catches by considering only damage on the spine. The
study did not evaluate all the effects on this species , which affects 15-39 % of cod sampled
against 7-11 % according to the study.
Indeed, this study on the comparison of the impact between the conventional beam trawl
and the pulse beam trawl recognizes damage to 7-11 % of cod caught. The counting of
physical damage on this species includes only fractures on the spine. But some cods have
significant bleedings that are not subject to evaluation. Overall, if we integrate all sequels,
it gets results rising from 15 to 39% of cod damaged.
On a sample of 18 cod caught using pulse beam trawl TX68, 2 suffer from fractures to the
spine and 5 show bleedings. The total damaged specimens were 7 of 18 individuals,
representing 39% of the sample against 11% according to the study of IMARES. For pulse
beam trawl TX36, if we add the specimens of cod which the spine is destroyed (2) to those
with bleeding (2) we obtain 4/27 or 15% of cod damaged.
Applying that range from 15 to 39% of cod damaged to the entire beam trawl fleet fishing
within ICES IIa , IV and VIId , ie 5% of the total catch of cod in the latter area , we obtain
a mortality between 250 and 650 tonnes of cod without considering the impact on
reproduction. [2013 = 33000 landed t X X 5% [ 15-39 %]] .
 Lack of transparency on the development of new pulse stimulation on twin-rigs: new
developments in electro-trawling are made.
An electrified twin-rig using pulse stimulation for catching plaice and sole is under
development under the Dutch “Masterplan Duurzame Visserij”. This kind of gear is also
expected to work on Nephrops grouds and the fished volume is five more higher than a
beam trawls.
In 2012, STECF recommended that any application of pulse technology in other gear types
should be considered only after an impact assessment on the effects of the new pulse gear
on the ecosystem, in particular when species not subject to a prior impact study.
 Major scientific issues : There are still many unknown points about the impact of pulse trawl,
including long -term effects of this practice on non-target species and their reproductive potential
: whiting,... and impact on the ecosystems : what is the effect of the electrical pulse to the
substrate, the substrate species like shell, whelk ... etc ?
Taken into account all this remarks, French fishermen are concerned about the increase of boat using
this forbidden gear (outside the current derogation). Members state involved in trial of pulse gear should
commit not to further increase the use of this technics before a proper ICES advice in that way is
released. For that purpose WGELECTRA should have access to all the studies (protocole, results…).