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THE CONFLICT BETWEENSTATIC GEAR AND MOBILE
GEAR IN INSHORE FISHERIES
Michel J Kaiser
04/09/2014 1
Structure of presentation
• Regulatory context• Diversity of inshore fisheries• Sources and evidence of conflict• Pros and cons of different fishing techniques• Performance and selectivity• Environmental impacts• Potential solutions
The conflict between static gear and mobile gear in inshore fisheries 204/09/2014
Inshore fisheries - complex regulations
The conflict between static gear and mobile gear in inshore fisheries 3
EU regulations
National regulations
Localregulations
12 nm6 nm
Land
200 nm
04/09/2014
Inshore fisheries characterised as ‘small-scale coastalfleets’, mostly <12 m and <10 m vessels
The conflict between static gear and mobile gear in inshore fisheries 4
Small-scale coastal fleet = 55% of total EU vessels, 6% in gross tonnage,25% in engine power, c. 52,000 FTEs (excluding Greece, Cyprus, Estonia,STECF 2013).
04/09/2014
Inshore fisheries – diverse fishing gear types
The conflict between static gear and mobile gear in inshore fisheries 5
a b
dc
Towedgears
Staticgears
04/09/2014
Sources of conflict
• Competition for the same biological resourceusing different fishing techniques
• Competition for access to same area of the seato fish for different target species
Examples: Baltic cod net fishery, Greek recreational and commercial
fishers, UK static (crustacea) and mobile gear (scallopers and trawlers)
The conflict between static gear and mobile gear in inshore fisheries 604/09/2014
Conflict between trap fishers and mobile gear
The conflict between static gear and mobile gear in inshore fisheries 7
Attitudes of mobile and static gear fishers to an inshore rotational management regimedemonstrate the dichotomy between the sectors
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Comparison of different gears
Advantages Disadvantages
Pot Low energy use and low habitat impactSelective (species and size)Flexible and transportableHigh catch quality, live bycatch
Low capture efficiency for many speciesGhost fishing of lost pots
Gill-net Low energy useFlexible and easily portableSize selectiveRelatively cheap to manufacture
Labour intensiveCatch quality a concernCapture of non-target speciesGhost-fishing of lost nets
Long-line Low energy use (depends)Minimal habitat impactFlexible and portableSpecies selective, good catch quality
Labor intensive, time consumingBycatch of non-target species (e.g. turtles)Snagging on benthic epifaunaAvailability and price of bait
Bottomseine
Relatively low energy useReduced sea bed impacts (light gear)Operation on smaller fishing groundsGood catch quality
Operation limited to cleaner grounds and shallowerdepths.Not effective for non-herding animals such asshrimp.
Bottomtrawl
Effective and reliableVersatile
Seabed impacts, fuel consumption, bycatch, costs,catch quality
The conflict between static gear and mobile gear in inshore fisheries 804/09/2014
Any fishing activity has some form of impacton the marine environment
The conflict between static gear and mobile gear in inshore fisheries 9
The majority ofstudies of staticgears have focusedon by-catch, veryfew have studieddirect physicalimpacts on theseabed and itsassociatedcommunities
04/09/2014
Selectivity and efficiency of different fleets
The conflict between static gear and mobile gear in inshore fisheries 10
VESSEL SEGMENT
AVERAGEVESSELLENGTH
(m)
ANNUALLANDINGS
PER VESSEL(t)
% OFTOTAL
DISCARDS
% OFQUOTA
DISCARDS
<10 m drift/fixed nets 8 21.6 16.7 6.0
<10 m demersal trawl/seine 10 27.0 16.7 5.9
Area VIIb-k trawlers 10-24 m 13 74.8 16.7 6.0
N.Sea beam trawlers<300 kW 14 74.9 15.6 5.7
N.Sea Nephrops<300 kW 14 90.9 22.6 8.1
Performance of towed gear and static gear approaching parity for some fleets
04/09/2014
Performance in relation to the number ofdiscards has improved for trawl fisheries
The conflict between static gear and mobile gear in inshore fisheries 11
Num
bers
Reasons:
• Large reductions infishing mortality
• Reductions in fleet size
• More selective gear
• Lack of any big yearclasses
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Secondary effects of fishing gear on the seabed
The conflict between static gear and mobile gear in inshore fisheries 12
The main environmental impact of towed gear is the physical contact withthe seabed leading to abrasion of habitats and associated communities
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Effects of towed gear on the physicalenvironment of the seabed
The conflict between static gear and mobile gear in inshore fisheries 13
100 m
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Inshore fisheries can affect deep seaenvironments in some parts of Europe
The conflict between static gear and mobile gear in inshore fisheries 14
In some areas of Europe trawlfisheries occur in habitats thatexperience low levels of naturaldisturbance.
These habitats are them moresensitive to fishing activities
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Inshore areas are subject to frequent naturaldisturbances
The conflict between static gear and mobile gear in inshore fisheries 15
The majority ofinshore fisheriesoccur in shallowwaters subject to highlevels of naturaldisturbance.
These habitats havevarying levels ofresilience to fishingactivities
Scallopdredgemarks
Adjacentunfishedseabed
with sandwaves
04/09/2014
The conflict between static gear and mobile gear in inshore fisheries 16
Some seabed environments arehighly mobile = resilient
Others are stable = sensitive
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The conflict between static gear and mobile gear in inshore fisheries 17
• Fishing is not uniformlydistributed
• Some areas are not fishedby gear that impact theseabed
• In the NE Atlantic thefootprint is diminishing
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The conflict between static gear and mobile gear in inshore fisheries 18
The distribution of fishing activity for >15 m vessels fishing off the coast of Sicily. The fishingactivity is highly aggregated and consistent between years. Note that large areas of the seaare not subjected to fishing. The stippled area close to the coast delineates the 50 m depthcontour within which no trawling is permitted. Although the Gulf of Patti is an area entirelyclosed to fishing (within the black line) there is clear evidence that fishers infringe the area tofish down the canyons that occur within this area.
04/09/2014
The conflict between static gear and mobile gear in inshore fisheries 19
As soon as we add colour to amap we embed an impressionthat much more of the seabed isfished
100% VMS coverageof all vessels fishing around theIsle of Man
Current EU legislation impedesaccess to this informationleading to errors in advice aboutenvironmental impacts
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The conflict between static gear and mobile gear in inshore fisheries 20
Impacts of different fishing gears vary with habitat and context
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The conflict between static gear and mobile gear in inshore fisheries 21
Trawling intensity (y-1)
Pro
du
ctio
n (
g W
W m
-2y-
1)
Bio
mas
s (g
WW
m-2
)
Tidal stress highWave erosion high
Tidal stress highWave erosion high
Tidal stress lowWave erosion low
Tidal stress lowWave erosion low
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The conflict between static gear and mobile gear in inshore fisheries 22
VMS has enabled us to test model predictions in the field
04/09/2014
The conflict between static gear and mobile gear in inshore fisheries 2304/09/2014
The conflict between static gear and mobile gear in inshore fisheries 24
Blyth et al. 2004 – mobile epifaunaBlyth et al. 2004 – sessile epifaunaHermsen et al. 2003Beukema 1995
0 2 4 6 8
Years
1.4
1.2
1.0
0.8
0.6
0.4
0.2
0.0
Biomass ratio
Understanding initial impacts is only half the story: post-fishing recovery isthe most important factor for managers
04/09/2014
The conflict between static gear and mobile gear in inshore fisheries 25
Investment inscience meanswe can maphabitat resilienceand hencemanage fishingimpacts on targetspecies and onhabitat features.
This hasimportantimplication forGES and theMSFD.
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What do we know about the impact of bottomset static gear on seabed communities?
• Coleman et al. 2013 – Inshore trap gear, noeffects detected – pseudoreplicated study
• Eno et al. 2000 – Inshore trap gear, no effectsdetected, study not replicated adequately
• Heifetz et al. 2009 – trap and long-line gear,effects detected on sensitive fauna, inferentialstudy but well analysed
The conflict between static gear and mobile gear in inshore fisheries 2604/09/2014
Recommendations• Rebuilding fisheries using FMSY
• Quantifying the footprint of inshore fisheries• Understanding static gear impacts on the seabed• Understanding what is impacted by inshore
fisheries• Improving communication between different
inshore fishery sectors• Reduce the ghost-fishing potential of static gear• Technical innovation to reduce physical contact
with the seabed• Integrated fisheries management for scallop and
static gear fisheries
The conflict between static gear and mobile gear in inshore fisheries 2704/09/2014
The conflict between static gear and mobile gear in inshore fisheries 2804/09/2014
Values used to calculate Energy Return OnInvestment (EROI) ratio of scallops from theRamsey Bay fishery.
The conflict between static gear and mobile gear in inshore fisheries 29
0.056
0.038
0.0191 Landings (kg) 23400
2 Average meat yield 20.24%
3 = ( 1 x 2 ) Total meat yield (kg) 4727
4 Protein content scallops(1) 16.7%
5 = ( 3 x 4 ) Edible protein from fishery (kg) 790
6 Fuel use (l) 12636
7 Specific gravity diesel (kg / l) 0.83
8 = ( 6 x 7 ) Fuel use (kg) 10487
9 = ( 5 / 8 ) EROI 0.075
04/09/2014