Low impact and fuel efficient fi shing—Looking beyond the horizon

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FisheriesResearch119–120 (2012) 135–146

ContentslistsavailableatSciVerseScienceDirect

Fisheries

Research

j o ur na l h o me p a g e :w w w . e l s e v i e r . c o m / l o c a t e / f i s h r e s

Review

Low

impact

and

fuel

efficient

fishing—Looking

beyond

the

horizon

Petri

Suuronen

a,∗

, Francis

Chopin

a

,

Christopher

Glass

b

,

Svein

Løkkeborg

c

,

Yoshiki

Matsushita

d

_,

_Dante

_Queirolo

e

_,

_Dominic

_Rihan

f

a_Food_and_Agriculture_Organization_of_the_United_Nations_(FAO),_Fishing_Operations_and_Technology_Service,_Viale_delle_Terme_di_Caracalla,₀₀₁₅₃_Rome,_Italy b_Northeast_Consortium,_Institute_for_the_Study_of_Earth_Oceans_and_Space,_University_of_New_Hampshire,_Durham,_NH_03824,_USA

c_Institute_of_Marine_Research,_P.O._Box_1870,_Nordnes,_N-5817_Bergen,_Norway

d_Graduate_School_of_Fisheries_and_{Environmental}_Studies,_Nagasaki_University,_Nagasaki_852-8521,_Japan

e_Escuela_de_Ciencias_del_Mar,_Facultad_de_Recursos_Naturales,_Pontificia_Universidad_Católica_de_Valparaíso,_P.O._Box_1020,_Valparaíso,_Chile f_Bord_Iascaigh_Mhara,_Crofton_Road,_Dun_Laoghaire,_Co_Dublin,_Ireland

a

r

t

i

c

l

e

i

n

f

o

Articlehistory:

Received1September2011

Receivedinrevisedform5December2011 Accepted9December2011

Keywords:

Ecosystemimpact Bycatch Fuelefficiency

Operationalimprovement Alternativegear Barrierstotransition Sustainablefishingpractices

a

b

s

t

r

a

c

t

Fishingprovideshighqualityseafoodandcreatesemploymentandincomeforpeopleworldwide.Most ofthecapturemethodsusedforfishingare,however,heavilydependentontheuseoffossilfuels.For manyimportantfisheriestheirhighconsumptionoffuelconstitutesamajorconstrainttotheireconomic viabilitybutalsorepresentsasignificantsourceofgreenhousegasemissions.Inaddition,fishing activ-itiescansometimesimpactthemarineenvironmentsthroughexcessiveremovalsofecologicallyand economicallyvaluablespeciesandalsobydirectphysicalcontactwithcriticalhabitats.Fishingpractices andgearsvarywidelyintheirenvironmentalimpactsandfuelefficiencybut,ingeneral,theimpactsof passivefishinggearssuchaspots,traps,andhooksareconsideredtobelesssevere,andtheamountsof fuelrequiredperkgofcatchsmaller,thanfortowedgearssuchasbeamtrawls,dredgesandthemany typesofbottomtrawls.Throughtechnologicalimprovementsandbehavioralchanges,thefishingsector cansubstantiallydecreasethedamagetoaquaticecosystems,reduceemissionsandloweritsfuelcosts. Changesinfishingpracticescanresultinmoreeconomicalandsustainablefisheriesthereby contribut-ingtoimprovedfoodsecurity.Barrierstobegintransitiontotheuseoflow-impact,lessfuel-intensive practicesandgearsincludeaperceptionthatcost-efficientandpracticalalternativesarenotavailable; restrictedaccesstocapital;ineffectivetechnologyinfrastructuresupport;andinflexiblefisheries man-agementsystemsthatrestricttherapiddevelopmentanduptakeofalternativegears.Thispaperdiscusses someofthekeycapturetechnologiesandidentifiesgaps,constraints,andopportunitiesthatfacilitate thedevelopmentandadoptionofLowImpactandFuelEfficient(LIFE)Fishing.LIFEfishingaddressesthe complexdynamicofenergyconsumptionandenvironmentalimpactswiththeobjectiveofimproving theeconomicviabilityandenvironmentalsustainabilityoffishingoperations.

Contents

1. Introduction... 136

2. Environmentalimpactsoffishingoperations... 136

3. Fuelconsumptionandgreenhousegasemissionsoffishingoperations... 137

4. LowImpactandFuelEfficient[LIFE]capturetechniques... 137

4.1. PotentialapproachesinLIFEfishing... 137

4.2. Increasingtheoperationalefficiencyandreducingseabedimpactsofdemersaltrawling... 138

4.3. Alternativefishingpracticesandgeartypes... 138

4.3.1. Bottomseining ... 138

4.3.2. Trap-netfishing... 141

4.3.3. Potfishing... 141

4.3.4. Hookandlines... 142

4.3.5. Gill-netting... 143

∗Correspondingauthor.Tel.:+390657055153;fax:+390657055188.

E-mailaddress:[email protected](P.Suuronen).

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136 119–120 (2012) 135–146

5. BarrierstothetransitiontoLow-ImpactandFuel-Efficientfisheries... 143

6. Conclusions... 144

Acknowledgements... 144

References... 144

1. Introduction

Globalcapturefisheriesproductionin2008wasapproximately 90milliontonnes,withanestimatedfirst-salevalueofUS$93.9 billion(FAO,2010).Whilethislevelofproductionhasbeen rela-tivelystableoverthepasttwodecades,therehavebeenmarked fluctuationsinthecatchesofmajorspeciesandthestocksofmany demersalhigh-valueresourceshavediminished.Anticamaraetal. (2011)estimatedthatoverthisperiodglobalfishingeffort(in kilo-watt days)hasincreasedby roughly 20 percentwiththemost pronouncedincreasesinAsia.Despiterecentreductionsof fleet sizesinmanydevelopedcountries,thesizeoftheglobalfishing fleethasdoubledinthelast30yearsandisestimatedatsomefour millionvessels(FAO,2010),about60%ofthesepoweredbysome formofengine.

Asmanyfishstockshavedeclinedduetoexcessivefishing, ves-sels oftenneed tosearch longerand/orfish in deeperoffshore waterswhich hasincreasedthefishingpoweroffishingvessels dramatically(WorldBankandFAO,2009)withgreateramounts ofgearbeingsetoveralargerareaanddepthrange. Technologi-calimprovementshavealsocontributedtoanincreaseineffective fishingpowerandefficiencysuchasthroughadvancedhydraulic powerapplications,strongermaterialsforfishinggearsandbetter electronicaidsfornavigation,bottommapping,fishfinding,gear deploymentandcommunication(Kristjonsson,1971;vonBrandt, 1984;Gabriel etal.,2005; Marchaletal., 2007).Many ofthese havebecomewidelyavailable,cheapandcompactenoughtobe operatedfromalmostanysizeofvessel.Foravarietyofreasonsa significantpartofglobalmarinefishstocksarecurrentlyeitherfully exploitedoroverexploited(FAO,2010)andtheeconomichealth ofmarinefisherieshasgenerallydeclined(WorldBankandFAO, 2009).

Mostfishingtechniquesinusetodayhave theirorigin inan erawhenfisheriesresourceswereabundant,energycostswere dramaticallylowerthancurrentlevels,andwhen lessattention waspaid tooperating efficiency and negative impacts of fish-ingonmarineandatmosphericecosystems.Currenthighenergy pricesandgreaterawarenessofecosystemimpactsarerealitiesand presentmajorchallengesfortheviabilityoffisheries.Thismaybe especiallytrueindevelopingcountrieswhereaccesstoand promo-tionofenergyefficienttechnologieshasbeenlimited(FAO,2007). Despiteagrowingnumberofinitiativesandexperimentationwith alternativeenergytechnologiessuchaswindassistedpropulsion (kitesandsails),compressedairengines,biofuelsandothers,there ispresentlynoviablesubstitutetotheuseoffossilfuelsfor pow-eringfishingvessels.

Withfossilfuelsremainingthedominantenergysourcefor cap-turefisheries,pursuingenergyefficiencymayrealizeamultitude of benefits such as reduced operating costs and environmen-talimpacts. However,theoverall successofany transitionwill dependheavilyondevelopingandapplyingsuitableandacceptable measurestoconventionalfisheriesandcreatingtheappropriate incentiveforchangeinthebehavioroffisherssuchasthroughthe developmentandimplementationofamanagementsystemthatis basedontheecosystemapproachtofisheries(FAO,2005;Fletcher etal.,2005;BianchiandSkjoldal,2008).

Modificationofexistinggears,developmentoflowdraggears andadoptionofalternativefuel-efficientgearsallrepresentmeans toimprovefuelefficiency.Thispaperdealswiththedevelopment

of“LowImpactand FuelEfficient(LIFE)”fishingwhichrefersto fishinggearsandpracticesthatensurefishcaptureoccursusinga lowamountoffuelwithlowimpactontheenvironment.It dis-cussessomeofthekeycapturetechnologiesandidentifiesgaps, constraintsandopportunitiestowardsdevelopmentofLIFE fish-ing.Inaddition,itexplorestransferandadaptationoftechnologies fromotherfisheriesthathavedemonstratedcommercialpotential forsimilarspecies.Theprimaryfocusisoncommercial capture-fisheries althoughsome environmentalissues concerningsmall scaleartisanalfisheriesarediscussed.Thepaperdealsmainlywith demersalfishing.

2. Environmentalimpactsoffishingoperations

Fishinggearsvarywidelyintheirimpactsonmarine ecosys-tems (Jennings and Kaiser,1998; Jennings etal., 2001;Bjordal, 2002;Tudela,2004;Kaiseretal.,2006;PoletandDepestele,2010) andwithoutaspecificcontexttheirrankingisextremelydifficult (MorganandChuenpagdee,2003;JenningsandRevill,2007;Fuller etal.,2008;GascoigneandWillsteed,2009;CaddyandSeijo,2011; Rochetetal.,2011).Impactscanbesplitintobiologicalandphysical impacts.Overallecosystemimpactslargelydependonthephysical characteristicsofthegear,themechanicsofitsoperation,where, whenandhowthegearisbeingusedaswellastheextentofits use.Gearsthatrankhighlyforonetypeofimpactmayhavealower rankfor another(Gascoigneand Willsteed,2009).Forinstance, dredgegearsmaygenerallyhaveahighrankforbottomimpacts (Løkkeborg,2005)buthavealowrankforbycatchofendangered, threatenedandprotectedspecies(ETPspecies).

Physicaldamagetothemarineenvironmentmayresultfrom thenatureofthecapturetechnologyor fromtheinappropriate useofanotherwiseacceptablegear.Forexample,theexploitation ofpreviouslyuntrawledgroundsbybottomtrawlscanresultina significantreductionintheabundanceofsensitivebenthic inverte-brates(Kaiseretal.,2006;Hiddinketal.,2006;Pitcheretal.,2009). However,itshouldbenotedthatuseofsuchgearonpreviously trawledground doesnotnecessarily equatetoincreased cumu-lativeimpacts.Onlyasmallnumberoffishingmethods,suchas explosivesandtoxins,arerecognizedasinherentlydestructive irre-spectiveofwheretheyareused(McManusetal.,1997;Barberand Pratt,1998;Garciaetal.,2003).

Somefishingactivities(e.g.shrimptrawling)capturea signif-icantquantityofspeciesandsizesbeyondthosetargetedleading totheincidentalcatchofawidevarietyoffishandinvertebrates includingjuvenilesofecologicallyimportantand/oreconomically valuablespecies. Thiscomponentof thecatchis frequentlynot retainedandisdisposedofoverboardasdiscards,whicharemostly deadormortallyinjured.During 1992–2001,theaverageyearly levelofdiscardsintheworld’smarinefisherieswasestimatedto be7.3milliontonnes(Kelleher,2005).Sincethistimetherehave beensubstantialeffortstomanagebycatchandreduce discard-ing(e.g.Broadhurst,2000;Halletal.,2000;Kennelly,2007;Zhou, 2008;ICES,2010;FAO,2011).Excessivelevelsofbycatchof non-targetspeciesandundersizedtargetspeciesstill,however,occurs formanyfisheries(Lewisonetal.,2004;Daviesetal.,2009).

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119–120 (2012) 135–146 137

butultimatelydie(Chopinand Arimoto,1995;Suuronen,2005; Broadhurstetal.,2006).Fishingcanalsoresultintheincidental mortalityofa varietyofendangered,threatened,protected and charismaticnon-targetspecies suchas seabirds,seaturtlesand marine mammals. Finally, some fishing activities may cause damagetovulnerablemarineecosystemssuchascoldwatercoral reefswhich cantakemanydecadesorcenturiestorecover(e.g. Lewisonetal.,2004).

Despite thevariability and complexity of the issue,and the factthatincidentalcaptureofnon-targetandcharismaticspecies isa probleminseveralpot,trapandhookfisheries,theoverall environmentalimpactsofthesetypesofpassivefishinggearsare generallyconsideredlesssevereincomparisontomanytypesof demersaltrawls, and in particularto dredges and beamtrawls (Bjordal,2002;MorganandChuenpagdee,2003;Valdemarsenand Suuronen, 2003;Fuller etal., 2008; Poletand Depestele, 2010; CaddyandSeijo,2011).Encirclinggears,thataredraggeda lim-iteddistanceatslowspeed,suchasbottomseines,aregenerally consideredlessdamagingthanbottomtrawls(Tulpetal.,2005; ICES,2006).Well-managedpurseseine fisheriesgenerally have minorecosystem impacts (Morgan and Chuenpagdee,2003).In somepurseseinefisheriesthereleaseofthecatchorportionsof thecatchfromseine(slipping)isacommonmethodofregulating thesizeandqualityofthecatch.Themortalityofpelagicspecies subjectedtoareleasemaybehighespeciallywhenthecrowding densityduringslippingishigh(e.g.HuseandVold,2010).Gillnets canbeanenvironmentallyfriendlyoptionbutmaybeproblematic duetonegativeimpactsonvulnerablespeciesorghostfishingby lostorabandonedgear(Rihan,2010).

3. Fuelconsumptionandgreenhousegasemissionsof fishingoperations

Fuelcostsforthefishingindustryhaverisensubstantiallyover thelastfortyyearsduringwhichtimetherewerethreemajorspikes whenoilpricesrocketed.Forinstance,between2003and2008the priceofcrudeoilrosefromUS$25perbarreltoUS$135perbarrel. Thisrapidincreaseseverelyaffectedtheprofitabilityofthecatching sector.Despite thedeclineofoilpricesafterthe2008peak,the mediumtermforecastsforoilpricesindicateahighlikelihoodfor furtherandsteadyincreases(InternationalEnergyAgency,2011).

FAOandWorldBankreportedthattheglobalfishingfleet con-sumesapproximately41milliontonnesoffuelperannumatacost of$22.5billion(WorldBankandFAO,2009).Thisamountoffuel generatesapproximately130milliontonnesofCO2 but thereis apaucityofdetaileddataonGreen HouseGas(GHG)emissions fromfishingvessels(e.g.Buhaug etal.,2009).While the inade-quatetechniquesforanalysismakeitdifficulttorankfishinggears andpracticesbytheirGHGemissions,relativefuelconsumption acrossmethodsoffersareasonablesurrogateforGHGemissions (exceptwhentheshare ofcatchrefrigeration is significant,see Wintheretal.,2009).Thosefisherieswhichareenergyintensive willtypicallyhavehigherGHGemissions.

Overall,approximately620Loffuel(527kg)isusedpertonneof landedfish(Tyedmersetal.,2005)butfuelconsumptionratevaries widelyaccordingtogeartypeandfishingpractice(Thrane,2004; Tyedmersetal.,2005;FAO,2007;Schauetal.,2009;Wintheretal., 2009).Operationaltechniquesandthedistancesbetweenfishing groundsandfishingports,aswellasvesseldesignand agewill allaffecttheamountoffuelconsumed.Therearealso substan-tialdifferencesin fuelconsumption betweenfisheries targeting groundfishorshellfishandthosetargetingpelagicfishorindustrial fish(Schauetal.,2009).

Studiesoffuelconsumptionpatternsbygeartypesreportthat passivefishinggearssuchaspots,traps,long-linesandgillnets gen-erallyrequireloweramountsoffuel(approximately0.1–0.4Lof

fuelperkgofcatch)thanactivefishinggearssuchasbottomtrawls (from0.5upto1.5L/kg).Bottomseinesrankbetweenpassivegear andbottomtrawlinfuelconsumption(Thrane,2004;Wintheretal., 2009;ICES,2010).Thevariationinfuelconsumption,however,can belargebetweenseinenetvesselsduetodifferentfishingeffort andsteamingtimestofishingground(Rúnarsson,2008).

Activepelagicgearslikemidwatertrawlsandpurseseines tar-getfishthatformdenseschoolsandenablethecatchofhundreds oftonnesoffishwithoneshorttoworhaul.Fuelconsumptionfor thesemethodsisgenerallylowinrelationtothequantityofcatch. Inparticular,purseseiningisoneofthemostfuelefficient tech-niquesforcatchingfish(approximately0.1Loffuelperkgofcatch) butthevesselsusingthisgearoftenspendsignificantlymoretime andthereforefuelsearchingforschoolsthanactuallycatchingfish (Thrane,2004;Schauetal.,2009;Wintheretal.,2009).

Fishingwiththehelp ofpowerfulartificiallightsis common practice in purse seining, squid jigging and stick-held-dip net-tingparticularlyinAsia.Whilethefishingoperationitselfisfuel efficient,theuseofthelightscanmakeitenergy intensive.For example, the coastal Japanese jigging boats (less than 20 GR), thatuseupto160kWelectricpowerforthelights,typically con-sumeabout600L offuelperoperationfor lightingtheselamps (Matsushitaetal.,2010).Tosaveenergy,theuseof low-energy LightEmittedDiodes(LEDs)hasemergedasanalternativewith fuelsavingsof20–30%butfishingefficiencymayalsobereduced (Yamashitaetal.,2012),andthereremainconcernsabouttheeffect oflightintensityontheenvironment(lightpollution).

Risingfuelcostshaspromotedresearchand developmenton variousenergysavingtechnologies(Curtisetal.,2006;Winther et al.,2009;Abernethy etal.,2010; Heredia-Quevedo,2010; E-Fishing,2010)butfuelcontinuestobeamajorcostandthecatching sectorremainsexposedtoprogressivelyincreasingfuelprices.In developing countries, mechanization continues to increase and highfuelpriceswillimpactsuchcountriesevenmorethan devel-opedcountries.Increasingfuelpricesoftenresultsingovernments establishingfuel-subsidiestosupporttheviabilityoffishing oper-ations(Sumailaet al.,2008,2010; World Bankand FAO, 2009) butsuchsubsidiesoftenworkagainstthedevelopmentof energy-efficientfishingoperations.

It isnoteworthythat lifecycleassessments (LCA)showthat significantenergyconsumptionandgreenhousegasemissionsare possibleevenafterthecatchistakenonboardandlandeddueto fishprocessing,cooling,packagingandtransport(e.g.Thraneetal., 2009;Wintheretal.,2009;Vázquez-Roweetal.,2011). Minimiz-ingimpactsandenergyconsumptionthroughouttheproductchain maybeanotherimportantelementneededtoreducethe environ-mentalcostsoffishing.

4. LowImpactandFuelEfficient[LIFE]capturetechniques

4.1. PotentialapproachesinLIFEfishing

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Fig.1.Asingle-boatbottomtrawldesignedtocatchspecieslivingonornearthe bottombytowingitsteadilyalongtheseabed.Thegroundgear(orthefootrope)of thetrawlhascontactwiththebottomwhilefishingandisdesignedtowithstand thisinteractionwithminimumdamage.Thehorizontalopeningofthenetmouthis maintainedbyotterboards.Floatsandweightsproducetheverticalopeningofthe net.

CourtesyofFAOandSEAFDEC.

scenariosthat willbeencountered duringfishing.Furthermore, wherefishingpractices arerootedintradition,thereisastrong resistancetochange.

Fuel consumption and ecosystem impacts can be reduced throughchangesinoperationaltechniquesandgeardesignwithout drasticchangesinbehavior(ValdemarsenandSuuronen,2003;van Marlen,2009;HeandWinger,2010;Rihan,2010).Thisapproach hasinmanycasesshownpromisingresultsandisoftenpreferredby thefishingindustry.Transitioningtoacompletelynewgeartype andfishingpracticeisanalternativethathasmanymore uncer-taintiesand highereconomicrisks.However,when incremental improvementsinexistingtechnologydonotallowlow-impactand fuel-efficientfishing,alternativepracticesand/orgearmayneedto beconsidered.

4.2. Increasingtheoperationalefficiencyandreducingseabed impactsofdemersaltrawling

Trawls(Fig.1)areflexiblegearthatcanbeusedonmanytypes ofareasandgrounds,inshallowanddeepwaters,andbysmalland largevesselsforawiderangeoftargetspecies.Thesecharacteristics havemadetrawlingthepreferredfishingmethodformanyfishers. Currently,trawlingmaybetheonlyeffectivesolutionfor captur-ingcertainspecies,forexamplecertain“shrimp”species.However, bottomtrawlinghasbeenidentifiedasoneofthemostdifficult methodstomanageintermsofbycatchandhabitatimpact.

Therearemanytechniquesandoperationaladaptations avail-abletoreducethedragandweightofthebottomtrawlgearand therebytoreducefuelconsumptionandseabedimpacts(Table1). Someof these techniques have been reported to reduce envi-ronmental impacts and gear drag withoutmarked decrease of thecatchofthetargetspecies(e.g.Glassetal.,1999;He,2007; Valdemarsenetal.,2007;Queiroloetal.,2009;vanMarlen,2009). ForinstanceinthebottomtrawlfisheriesinMexico,Colombiaand Chile,severalmodificationshavebeensuccessfullytestedintrawls toreducebycatchandfuelconsumption.Areductionofthegear dragbetween20and35%andfuelsavingbetween23and43%have beenreportedinthesetests(Zú ˜nigaetal.,2006;Rico-Mejíaand Rueda,2007;Meloetal.,2008;Heredia-Quevedo,2010).

Moreworkisneededtoimprovetheconstructionofdifferent componentsoftrawlgeartominimizefrictiononthebottomand

Fig.2.Abottomseinehaslongtowingropesextendingfromthewingsofthenet thatherdthefishintothepathofthenet.Theboathaulsropessimultaneously whensteamingslowlyforward.Thehaulingspeedoftheropesisincreasedgradually towardstheendoftheoperation.

CourtesyofFAOandSEAFDEC

toreduceoverallgeardrag.Technologyshouldbefurther devel-opedtoautomaticallymeasureandadjustpressureoftrawldoors andgroundgearontheseabed.Anexampleofthisapproachisa systemdevelopedinSpaintocontrolthebottomfishinggearof thefleetoperatingclosetoagaspipeline(ICES,2010).Inthiscase, thesystemmonitorsandrecordsfishinggearparameterswiththe geographicalpositionofeachsensor(installedonthedoorsandthe headropecenter)relativetothepipeline.Thisallowsvesselsinthe vicinityofthepipelinetoraisetheirgearoveritwithoutdamageto theirgearorthepipeline.Oneexamplewhereseabedcontacthas beenreducedwhilecatchingefficiencywasmaintainedistheuse ofballastelementsordropperchainstoholdthefootropenear,but notcontacting,thebottom(HeandWinger,2010).Insomefisheries movingfrombottomtrawlingtosemi-pelagictrawlingcanmake trawlingactivitiesmoresustainableandenergyefficient(Jørgensen andValdemarsen,2010).

Inbeamtrawls,progresshasbeenmadeinrecentyearsin devel-opingalternativegeardesignsthatreducetheamountoftickler chains,avoidexcessweightinthebeams,anduseotherstimuli(e.g. electricpulses)asanalternativetochainstoscarethetargetfish offthebottomandintothenet(PoletandDepestele,2010).The useofacoustic,light,oranyotheradditionalstimulitoenhance encountersbytargetspecieswithinthecatchingsphereoftrawl netsshouldbefurtherexplored.

Theuseof improvedlocation and targetingof fishwiththe helpofelectronicseabedmappingtoolsandintegratedGPS nav-igationsystems,have resultedinavoidanceofsensitivebottom habitatsandminimizefishingeffortandfuelconsumption. Multi-beamacousticshasbeensuccessfullyappliedtomappingscallop bedsontheBrownsBank,NovaScotia.Byapplyingfine-scale acous-ticmappingofbeds,theCanadianscallopfisheryonBrownsBank hasbeenabletoreducefishingtimeandtowingdistanceby70% between1998and1999whilestill harvestingthesamescallop quota(NationalResearchCouncil,2005).

4.3. Alternativefishingpracticesandgeartypes

4.3.1. Bottomseining

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Table1

Examplesofpotentialenergysavingtechniquesandoperationaladaptationstoreducefuelconsumptionandenvironmentalimpactsofdemersaltrawling.

Technique/measure Effect Constraints–barriers

Useofthinnerandstrongertwines,superfibres, knotlessnetting,squaremeshnetting,T90net,less netting,largermeshsize

Reducestheamount,weightandsurfaceareaof nettingandincreaseswaterflowthroughthenet, therebyreducingtheoveralldrag

Highpriceandavailabilityofmaterials;useof largermeshescanreducethecatchofmarketable speciesandsizes;costbenefitanalysesnotcarried outformostfisheries

Useofsmallerand/ormultiplenetsforspeciesthat exhibitpooravoidancebehaviortothepresenceof thefishinggear(e.g.shrimp,flatfish)

Reducestheoverallnettingsurfaceareaand therebytheweightandthedragwithoutreduction incatch

Policy,complexityofrigging,resistancetochange

Useofeffectivebycatchandbenthosreductiondevices (BRDs)

Allowstheescapeofunwantedspeciesorsizesof fishandotherunwantedobjectstherebyreducing theweightandoveralldrag

Variabilityinperformance,lackoftechnical supporttotestandoptimizeBRDs,lossofrevenues oftargetspeciesandsizes,perceptions

Usingfour-paneldesign(insteadoftypicaltwo-panel) inthebelly,extensionpieceandcodend,using squaremeshnettinginthebelly

EnsureseasierinstallationofBRDsandbetter geometryandstabilityforthebackendofthetrawl

Costbenefitanalysesnotcarriedoutformost fisheries

Useofhydrodynamictrawldoorsanduseofoptimal warplength(thatcorrespondstooptimaldoor efficiency)

Lessdrag(traditionaltrawldoorscontributeupto 25-35%oftheoverallgeardrag),lessweight,better fuelefficiency

Price,performancemonitoring,controlindifferent seaconditionsanddepths

Useofraisedorflyingtrawldoorswheretheweight elementofthedoorisseparatedfromthespreading element(doorscanbeflownabovetheseabedto openthetrawl)

Betterspread,lessdragandlesspressureonthe bottom(lessseabeddisturbances)

Price,performancemonitoring,controlindifferent seaconditions,depths,notsuitableforallspecies

Betterriggingofthegear,lighterground-gear,shorter ground-gear,lessdiscsandbetterrotationcapacity, self-spreadinggroundgear,compositeropes, lengthenedbridles,off-bottombridles,lightweight warps,andpropermatchingoftrawlnetandtrawl doors

Lighterandreducedcontactpointstoseabed,less seabedpressure,smallerimpactarea,lessdrag

Performancemonitoring

Useofhydrodynamicshapeoffloats,kites,beams, pulsetrawls,SumWing-design

Reduceddrag,reducedseabedcontact Performancemonitoring,speeddependence

Convertingfromsingleboattrawlingtopairtrawling Reducesfuelconsumption,lessseabeddamages Policy,humanbehavior

Improvingreal-timemonitoringandcontrolofgear withacousticgearsurveillancetechnology

Maintenanceofoptimalgearperformance,reduces energyconsumptionandbycatch

Price,training

Installingreal-timecameraobservationsystemfor informingskipperoffishbehaviorandcomposition inthetrawl

Helpstomaintainoptimalgearperformance, reducesbycatchandcollateralimpacts.Thenext stepmaybeanactivemechanismtorelease unwantedcatch

Price,training

Improvingnavigationandfishfinding,andimproving knowledgeonfishinggrounds(GPS,electronic charts,sea-bedmapping)

Maximizescatchesandminimizestime,energy andcollateralimpacts

Price,training

Useofspeedcontrols,reductionoftowingspeed Reducingspeeddirectlyreducesthefuel consumption

Humanbehavior

Vesselandpropulsionsystemoptimization,preventive maintenanceofvesselandengine,changeintrip planningpractices

Reducesfuelconsumption Price,humanbehavior

ontheseabed.Thelightgearandlowhaulingspeedmeansthat fuelusagemaybelowerthanforacomparabletrawlingoperation. Aseineischeaperandlessbulkythanatrawlandcantherefore beaneffectivetechniqueforsmallerandlowhorsepowervessels, dependingonthetargetspecies. Nevertheless,there areseveral operationallimitationsinseinenetting(Table2).

Bottomseinenetsaregenerallyregardedashavinglowimpact on benthos, although few specific studies have measured this impact(ICES,2006).Tulpetal.(2005)derivedfishingevent mor-talityratesforfourmainfishinggearcategories,includingbottom seine.Gearaveragemortalitiescalculatedacross12benthic inver-tebratephylawere0.25for beamtrawl, 0.1fortwo ottertrawl fisheries(Nephropsandmixedroundfish)andonly0.05forseine gears,showingseinestohavethelowestmortalityfortowedgears.

TwoCanadianreviewsrecentlyconcludedthatthemainimpact ofseiningisbycatchofbothundersizedindividualsofthetarget species and individuals of non-targetspecies (Donaldson etal., 2010;WalshandWinger,2011).Intermsofother environmen-talimpacts,includingbycatchofprotectedspeciessuchasmarine mammals,pinnipedsandseabirds,therearenoreportedimpacts otherthanafewbenigninteractions.InAustralia,some interac-tionswith sealsare noted by Wayte et al. (2004)but with no resultantmortality. Donaldsonet al. (2010)reported bycatches of winter skate (Leucoraja ocellata) by seiners in the Southern Gulf of St. Lawrence, a species that has been listed as endan-gered.

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Table2

Potentialadvantagesanddisadvantagesofdemersalgearexploredinthisstudy.

Gear Advantages Disadvantages Priorityactions

Trap-netandpound-net •Lowenergyuse

•Selectiveforspeciesandsizes(if

properlydesigned)

•Livecapture(possibility) •Minimalhabitatimpact

•Noteasilyportable

•Operationmaybelaborintensive •Maintenancelabor-intensive •Expensivetoconstruct

•Operationlimitedtorelativelyshallow

waters

•Occasionallysignificantbycatches

•Developmentofdesignsand

practicesthatpreventtheentangling ofnon-fishspeciesinthemooring ropesandnettingsofthetrap

Pot •Lowenergyuse

•Flexibleandtransportable •Canbeoperatedinroughbottoms •Selectiveforspeciesandsizes •Livecapture—goodcatchquality •Potentialforlowbycatchmortality •Minimalhabitatimpact

•Predatorsafe

•Availabilityofwidevarietyof

suitablelocal(natural)materials

•Cheaptoconstruct

•Lowcaptureefficiencyformanyfinfish

species

•Ghostfishingoflostpot

•Lostpotscontributetomarinedebris •Lowcatchrates

•Fishbehaviorstudiestoenhance

ingressandreduceescape

•Alternativeattractants •Comparativefishingexperiments •De-ghostingtechnologies

•Humanbehavior–barrierstoachange •Researchanddevelopmentworkat

infancy

•Laborintensiveandtimeconsumingto

operate

•Incidentalbycatchofnon-targetspecies •Snaggingonbenthicepifauna •Availabilityandpriceofbait •Lowcatchrateformanyspecies

•Baitissue/baitavailability

•Possibletotargetspecificsizerange

allowingeffectiveexclusionofsmall andlargefish.

•Relativelycheaptomanufacture

•Laborintensive

•Mostfishdieduringcapture •Catchquality

•Poorspeciesselectivity

•Captureofnon-targetspecies,oftenseabirds,

turtlesandothercharismaticspecies

•Ghostfishingoflostnets •Benthicimpacts

•Developmentofpracticesand

technologiesthatreducebycatch

Bottomseine •Relativelylowenergyuse

•Possibletooperatewithlow

horsepowervessels

•Reducedbottomimpactscompared

tobottomtrawling

•Requireslessspacethanbottom

trawling(possibletooperateinsmall patchesofgoodground)

•Allowseasymovingbetweenfishing

ground

•Relativelylowgearcosts •Lessgeardamageandwearthanin

bottomtrawlfishery

•Easiertouseandrepair(thanbottom

trawl)

•Highfishquality

•Greatscopeformodificationsand

improvements

•Notasflexibleandeffectiveasbottom

trawling

•Operationlimitedtorelativelyflatandclean

grounds(warpssnageasilyonboulders)

•Operationcanalsoberestrictedbydepth,

strongtides,badweatherandlackofdaylight

•Noteffectivefornon-herdedanimalssuchas

shrimpandnephrops

•Operationrequiresgoodskills •Workloadcanberelativelyhigh •Relativelypoorselectivityforspeciesand

sizes

•Potentialseabedimpacts •Alargeseinecanbeexpensiveto

manufacture

•Researchanddevelopmentwork

neededinimprovingtheoperationon roughgrounds,inseacurrents,andin deeperwaters

•Substantialenergysavingpossibility •Trainingisneededbecausethe

technologynotwellknown

Beamtrawl •Effective

•Relativelyeasyandpracticaltouse

•Seabedimpacts •Highfuelconsumption •Bycatch

•Suitableonlyforrelativelycleangrounds •Expensive

•Operationrequireshighskillsandadvanced

equipments

seeTable1

periods of the capture process leading to higher catch quality relative to trawling where fish collectin the codend through-outhaulsoften lastingmany hours.In Norway,bottom seining is the mostwidely used fishing method to collectfish for the

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119–120 (2012) 135–146 141

Fig.3. Atraditionalstationarytrap-net(pound-net)mountedonstakesinshallow water.Trap-netsoftenhavealongleadernetplacedacrossthepathofmigrating fishtoguidethemtowardstheholdingchamberfromwhichescapeishamperedby funneldevicesorgorges.

4.3.2. Trap-netfishing

Trap-nets(Fig.3)arepassivefishinggearsthathaveevolved fromsimplebarrierstomodern-daynettingenclosureswith herd-ingandretainingdevices.Theyareusuallysetontraditionalsitesin thepathofmigratingfishincoastalwaters.Leader-nettingherds andguidesfishintoaholdingchamberorpoundwheretheyare entrappedandretained.Designsareuniquetoparticularlocations (Slack-Smith,2001;HeandInoue,2010).Trap-netfisheriescanbe energyefficient,selectiveandhabitat-friendlyprovidingcatchesof highqualitysincethecatchisusuallyalivewhenbroughtaboard thevessel.Thebenefitsoflivecapturetechniquesprovidethe oper-atorwithagreaternumberof options– tosellimmediately,to controlsupply tothemarketortoholdandgrow/fatten–allof whichcancontributetoaddedvalueofthecatch.

Thepontoontrap(Fig.4)isanewinnovationandoffers vari-ousadvantagescomparedtotraditionaltrap-netssuchaseasyto transport,handleandhaul,andisadjustableintermsofsize,target speciesandcapturedepthaswellasbeingpredator-safe(Suuronen etal.,2006;Hemmingssonetal.,2008;LehtonenandSuuronen, 2010;Lundinetal.,2011).Potentialnewinnovationsmayinclude large-scale ocean-based fish traps which may use chemical,

Fig.4. Apontoontrapoffersvariousadvantagescomparedtotraditionaltrap-nets suchaseasytransportationandhauling.Itisadjustableintermsoftargetspecies andcapturedepth.Thispontoontraphasattachedanadditionalsmallertrapfor live-captureofsealthatattempttoenterthegear.

CourtesyoftheFinnishGameandFisheriesResearchInstitute.

electrical,lightoracousticattractants.Alargestationarytrap-net mayattractmarinelifeandfunctionasanartificialreef.This charac-teristichasattractedresearchanddevelopmentworkparticularly inAsia(Jeng,2007).Incidentalcaptureofnon-targetspeciesisa probleminsometrap-netfisheries,anddevelopmentofdesigns andpracticesthatpreventtheentanglingofnon-fishspeciesinthe nettingandmooringropesofthetrapareneeded(Table2).

4.3.3. Potfishing

A pot is a small transportable cage or basket with one or moreentrancesdesignedtoallowtheentryoffish,crustaceansor cephalopods,andpreventorretardtheirescape.Potsareusually setonthebottom,withorwithoutbait,singlyorinrowstethered toasingleline,andconnectedbyropetoabuoyonthesurface. Theycanbehauledbyhandormechanizedpothaulers.

Potsareextensivelyusedinthecaptureofcrustaceanssuchas lobsterandcrab(e.g.Krouse,1989; Miller,1990;Ahumadaand Arana,2009).Theuseofpotsforcapturingfinfishhasalong tradi-tioninmanypartsoftheworldbuthasprogressivelydeclinedsince the1960satleastpartlyduetotheintroductionofnylongillnets andtheexpansionofdemersaltrawling(Thomsenetal.,2010).Pots typicallyhaverelativelylowcaptureefficiencyforfinfish,especially whencomparedtogearssuchastrawls,seinesandgillnets. How-ever,potsareaneconomicallyviablefishingmethodforPacificcod andsablefishintheGulfofAlaskaandtheBeringSea(Thomsen etal.,2010).Theyarealsosuccessfullyusedinfisheriestargeting coralreefspeciesinhabitingareaswheretheuseofactivegearsis bannedornotpractical.

Pots, liketrap-nets,possess severalappealing characteristics comparedtomanyotherfishinggears:lowenergyuse,minimal habitatimpact,highquality,andlivedelivery(Slack-Smith,2001; Thomsenetal.,2010;Table2).Potscanbeleftinthewaterforalong timeandthecatchisstillretainedingoodcondition(O’Brienand Dennis,2008).Somefisheriesthatspecificallytargetthecapture oflivefishhavedevelopedpotsastheprincipalcapturemethod. Live-capturemaybringasubstantiallyhigherpricetothefisher. Wherethequalityofthecatchiscritical,potsmaybethepreferred capturemethod.Whilepotfishingvessels,ingeneral,havelowfuel use,somefisheriesexhibithighfueluse.Forinstanceinthelobster fisheriesintheGulfofMaine,onevesselmaysetover 800pots pertrip,andliftmultiplepotsperday.Theseoperationsrequire steamingathighspeedsoverlongdistances.

Because fish usually remain uninjured in the pot until it is hauled,unwantedbycatchorganismscanbereleasedwithahigh probabilityofsurvival,althoughfactorssuchasairexposure, baro-traumas,orthermalshockmayjeopardizesuchpotentialbenefits (Broadhurstetal.,2006).Bycatchfrompotscanbeminimizedby usingappropriate baits, meshsizes, materialsandchoosing the correct size,shape, location and design ofentrance and escape openings(Boutsonetal.,2009;Aranaetal.,2011;Table2). Never-theless,thepotentialforreducingunwantedbycatchandincidental mortalityinpotfisheriesrequiresfurtherinvestigation.

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142 119–120 (2012) 135–146

Fig.5. ANewfoundlandcollapsiblecodpotisbeinghauledonboard. CourtesyofPhilipWalsh, FisheriesandMarineInstitute,MemorialUniversity, Canada.

1994). Therelease rateof odor(attractant) froma natural bait decreases rapidly over time (Løkkeborg, 1990). A system that prolongstherelease ofbait odorand in whichtheodorplume (dispersal)iscontrolledcouldincreasepotefficiency.Researchhas shown thatlow catchingefficiency of potsis oftendue to low ingressrateratherthanlownumbersoffishbeingattractedtothe gear,anduseofadditionalstimulisuchaslightandsoundmay triggermorefishtoenterapot(Thomsenetal.,2010).Morework isneededtodefineoptimalbaitingstrategyandthepotentialfor usingartificialbaits.

Collapsible(foldable)potsmadeofpolyethylenenetting(Fig.5) have recently been tested on the east coast of Canada with promisingresultsforAtlanticcod(Safer,2010;SullivanandWalsh, 2010).Fishremainedaliveinthepotsuntiltheywerehauledand fishersreceivedsignificantlyhigherpriceofthesefishcompared tothegillnet-caughtfish(Safer,2010).Afloatingpotdeveloped inNorwayforcodprovidesanotherexampleofaninnovativepot designthathasshownsignificantpotential(Fureviketal.,2008). Floatingthepotoffbottomallowsthepottoturnwiththecurrent sotheentrancealwaysfacesdowncurrentresultinginsignificantly highercatchrateoftargetcod. Floatingthepot offbottomhas provedtobeaneffectivewaytoavoidnon-targetcatchofcrabs, andmayalsoreducetheseabedimpactscomparedtoapotsitting onthebottom.Thesametypeoffloatingpothassuccessfullybeen testedinSwedenasanalternativetothegillnetfisheryforcodthat facesproblemswithdepredationbyseals(Ovegårdetal.,2011).

4.3.4. Hookandlines

Hookandlines(Fig.6)refertogearswhichfish,squid,orother speciesareattractedbynaturalorartificialbait,orlureplacedon ahook,onwhichtheyarecaught.Hook-and-linegearmaybeused withonehookorwithlargenumbersofhooks,eachfixedtothe endofaline.Widevariationsinhookandlineconfigurationand theirmodeofoperationhavemadethemaneffectivegeartype forawidevarietyofspecies(George,1993;BjordalandLøkkeborg, 1996;Thomasetal.,2007;Løkkeborgetal.,2010).Itisaversatile fishingmethod,employedbyawiderangeofvesselsfromartisanal boatstolargemechanizedlong-liners withon-boardprocessing andfreezingplants.Hookandlinefishingisgenerallyconsideredan environmentallyfriendlybutlabor-intensivefishingmethodthat catchesfishof veryhighquality (Table2).Fuelconsumption in thesefisheriesisrelativelylowalthoughitcanbeincreased signif-icantlydependingonthedistancesvesselshavetotraveltofishing ground(e.g.coastalhookandlinefisheriesversushigh-seastuna long-lining).Inaddition,wherenaturalbaitisused,theremaybe

Fig.6. Abottom-setlong-lineconsistsofahorizontalmainlinewithsnoods (gan-gions)andbaitedhooksattachedatintervals.Thegearisusuallyanchoredateither endofthelinewithweights.Thelengthofthelonglinecanrangefromafewhundred meterstomorethan50km.

aneedfortargetedfishingactivitytoobtainthebaitandthiswill increasethetotalamountoffuelburned.

Thecaptureprincipleofhookandlinefishingistoattractfish tohooksusingodor-releasingbaitalthoughthevisualstimuli pro-videdbythebaitmayalsoplayarole.Thecharacteristicsofthe baitarefundamentallyimportantin thecaptureprocess; hook-ingprobabilityisspeciesspecific,whilelargerbaitstendtocatch largerfish(LøkkeborgandBjordal,1992;BjordalandLøkkeborg, 1996).Theshapeofthehookaffectsnotonlythehookingrates butalsothetypesoffishcaught.Moreresearchshouldbeaimedat thedevelopmentofalternativebaitsbasedonsurplusproductsor wastematerials(Løkkeborg,1991;Ericksonand Berkeley,2008) since mostbaitsusedtoday aremade fromfishand otherraw materialsthatmightbebetterusedforhumanconsumption.Bait alsohasahighassociatedcostinmostlong-linefisheries,asthese resourcesalsoaresoldforconsumption.LightsticksandsmallLED lightsareoftenusedinpelagicfisheriestargetingswordfish(Hazin etal.,2005).Awideruseofpotentialnewattractantsinlong-line fisheriesshouldbeexploredfurther.

Long-linefishingcancausetheincidentalmortalityofseabirds, sea turtlesand sharks, many of which are either protected or endangered (Montevecchi, 2001; Erickson and Berkeley, 2008; Løkkeborg,2011).Becausebycatchinteractionsmayreducegear efficiency(andprofitabilityoffishing)duetotheassociatedloss ofbaits,itisintheinterestoffishermentoreducesuch interac-tions.Thereareseveralmitigationmeasurescapableofreducing thelikelihoodofincidentalseabirdandseaturtlebycatch(Gilman etal.,2005;FAO,2009;Løkkeborg,2011;Gilman,2011).Long-lines setwitha streamerlineinordertodeterseabirdsfromseizing thebaitedhooksgave32%highertargetcatchratesthanthoseset withoutthismeasureinademersallong-linefishery(Løkkeborg, 2011).HookdesignssuchastheCircle-hookand“weakhook”have successfullybeendevelopedtohelpincreasethesurvivalratesof animalsthatarereleasedfromthehookbuttheeffectsarespecies specific(Yokotaetal.,2006;NMFS,2011).EricksonandBerkeley (2008)demonstratedthatartificialbaitscanreducebycatchon cer-tainunwantedspeciessuchassharkswhilemaintainingcatchrates oftargetspecies.

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Fig.7. Abottomsetgillnettypicallyconsistsofasinglewallofnettingheldvertically inthewaterbyafloatlineandweightedgroundline(leadline),andkeptstationary byanchorsorweights.

fisheries offer the potential to conduct fishing without severe habitatdamagerelativetomanyothermethods.Thepotentialfor catchingspeciesthatarenotcurrentlypursuedwithhookandline gearshouldbeinvestigated.

4.3.5. Gill-netting

Bottomsetgillnets(Fig.7),encompassinggillnets,entangling nets and trammel nets,are widely usedthroughout theworld. Improvedmaterialsandtechniqueshaveallowedtheexpansion ofsuchgeartoroughergroundsincludingwrecksandreefsand deeper waters (He and Pol, 2010). Gill-netting is a versatile, fuel-efficientand flexible fishing methodbut can alsobe labor intensivebecausethefishersmustmanuallyreleaseoruntanglethe catchfromthenet.Withtheexceptionoftrammel-nets,the size-selectivityforfinfishisgenerallygoodbut,dependingonspecies assemblagesin theareafished,species-selectivitymaybe poor (ValdemarsenandSuuronen,2003).

Fishcaughtbygill-nettingareoftenmortallyinjuredduring cap-ture,accordinglycatchistypicallyoflesserqualitythanwithpots, trapsandlong-lines.However,whensoak-times(i.e.thetimethe netisleftinthewatertofish)areshortgillnetsmayprovidecatches ofrelativelyhighquality.Inacomparativeexperimentconductedin Canada,themortalityforgillnet-caughtAtlanticcodwaslow(<5%) at6hsoaktimebutraisedtoabout30%with12hsoaktimeand continuedtoincreasewithlongersoaktimes(O’BrienandDennis, 2008).Potsandlong-linesshowedsignificantlyhighersurvivaland fishquality.Thepracticeofleavingnetsatseawithlongsoaktimes oftenleadstohighdiscardingofdeadandpartlydecomposedcatch. ThisisaproblemforinstanceinmanyNEAtlanticgillnetfisheries (Hareideetal.,2005).

Anydirectbenthicimpacts fromgillnetfishingoperationsis likely to occur only during retrievalof the gear, during which thenetsandleadlinesaremorelikelytosnagbottomstructures. Inparticular,reef-formingorganismsandothersessileepibenthic organismsfrequentlybecomeentangledingillnetsandare dam-agedwhenthenetsarehauled.Likewise,thecaptureofseabirds, seaturtlesandmarinemammalsbygillnetshasreceivedincreased attention(Davoren,2007;Gilmanetal.,2010;Rihan,2010).These problemscanbereducedbyvariousgearmodificationsbutthese mayreducethecatchingefficiencyofnetsforcertaintargetspecies (ValdemarsenandSuuronen,2003;Løkkeborg,2011).Moreover, efficientmeasurestoreduceseabirdbycatchingillnethavenotyet beenidentified(Løkkeborg,2011).

Thereis concernabout impacts ofghostfishing bylost and abandonedgillnetswhichmaycontinuetofishforseveralweeks, monthsorevenyears,dependingontheirconstruction,thedepth, andprevailingenvironmentalconditions(Humborstadetal.,2003; Hareideetal.,2005;BrownandMacfadyen,2007).Thisproblem canbepartiallyaddressedbytheuseofbiodegradablematerials orothermeanstodisableunattendedgillnets(Matsushitaetal., 2008).However,commerciallyviablesolutionsarefewifany. Bet-terresultsmightbeobtainedbyincreasingeffortstoavoidlossof gillnets,orbyfacilitatingthequickrecoveryoflostnets.Insome areas,gillnetfishinggroundsareperiodically“swept”forlostnets. Lostgillnetsarecommoninareaswherebottomtrawlingactivity ishigh,sincethetrawlgeardisplacesorcutsthenets,ortheirbuoy lines.Abandonedgillnetshavebeenidentifiedasaparticular prob-lemindeeperwatersandwhenlongfleetsofgillnetsaredeployed (Hareideetal.,2005;BrownandMacfadyen,2007;Grahametal., 2010).Manyoftheseproblemscanbemitigatedbybetter cooper-ationbetweenfishergroupsthroughthedevelopmentofcodesof conduct.Gillnetfishingrequiresacarefulselectionofthefishing ground.

5. BarrierstothetransitiontoLow-Impactand Fuel-Efficientfisheries

Throughtechnologicalimprovementsandbehavioral change, capturefisheriescandecreasethedamagetoaquaticecosystems, reduceemissionsandlowerfuelcostswithoutexcessiveimpactson fishingefficiency.Eachfishinggearandpracticedescribedherehas advantagesanddisadvantages(Table2),andthesuitabilityofeach gearlargelydependsontheconditionsandspeciestobetargeted. Despitethis,therearebarrierstothetransitiontolow-impactand lessfuel-intensivepracticesandgears(Glassetal.,2007;Jennings andRevill,2007;GascoigneandWillsteed,2009).Theseinclude:

•lackoffamiliaritywithcost-effectiveandpracticalalternatives; •availabilityoftechnologies;

•incompatibilityofvesselswithalternativegear; •riskoflosingmarketablecatch;

•additionalwork;

•concernswithsafetyatseabyusingunfamiliargearsor strate-gies;

•highinvestmentcosts;

•lackofcapitalorrestrictedaccesstocapital; •ineffectivetechnologyinfrastructuresupport;and •inflexiblefisheriesmanagementsystems.

Rigid regulatoryregimescancreate problemsthat fishersmust solveandthismayeffectivelydenyfisherstheflexibilityrequired toinnovateandadoptnewtechnologies.Furthermore,theabsence of uptake byallfishers mayputanindividual fisherat a com-mercial disadvantage.Fromanindividual fisher’spoint of view thefundamentalquestionis:whataretheeconomic benefitsin switchingtonewgears andpractices. Fishers willnotwillingly adopttechniquesthattheyfearwillincreasecostsand/or work-loadandreduceearnings.Fishingeffectivenessandpracticalityof newdesignsareimportant.Aninefficientgearwillnotbeused.

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spaceinwhichtooperateasefficientlyaspossible.Onepossibility istoallocatetoLIFE-fishingextraquotaorpreferentialaccessto specificfishingareas.Reducingthe‘racetofish’byimposing indi-vidualquotascanfacilitatetheadoptionofLIFEfishingpracticesin somefisheries.

Understandingthe“humanbehaviorbarriers”thathavetobe overcomeandwhatthecatalyticdriversmightbethatcouldchange thesebehaviorsis criticallyimportant(Branchet al.,2006;Hall et al., 2007; Gjertsen et al., 2010). Christy (2000) argued that inmanysmall-scalefisheries,a decentralizedcommunity-based managementwouldmosteffectivelypermitfisherstoadoptthose measuresandpractices,mostsuitablefortheirparticularsituation andthemostsustainableoptioninthelongrun.Healsoargued thatashifttomorestationaryfishinggearswouldimprovethe abil-ityofthecommunitiestoestablisheffectivefisheriesmanagement systems.Gutiérrezetal.(2011)demonstratedthecritical impor-tanceofprominentcommunityleadersandrobustsocialcapital, combinedwithclearincentivesthroughcatchshares,in promot-ingsuccessfulfisheriesandmanagementofaquaticresources.They identifiedstrongleadershipasthemostimportantattribute con-tributingtosuccessinfisheriesco-management.Interestingly,the researchshowedthatlessimportantconditionsincluded enforce-mentmechanisms,long-termmanagementpoliciesandlifehistory of the resources. It is also obvious that where fish are more abundant,the relative competitiveness of passive fishing gears improves.Restoration of depleted fish stocks is fundamentally importanttothesuccessofLIFEfishing.

6. Conclusions

Withcontinuedexposuretorisingfuelprices,thefishing indus-trywillcontinuetosufferalossinprofitability.Itisapparentthat ifresourceabundanceandfishpricesremainstatic,some conven-tionalbottomtrawl,beamtrawlanddredgefisheriesmaybecome uneconomic while passive gear fisheries or seine net fisheries shouldbelessaffectedbythesepressures.Sincecapture produc-tionfromdemersaltrawlfishingcurrentlyformsasignificantpart oftheworldcatchfordirecthumanuse,thisscenariocouldhavea majoraffectonglobalfishsupplyandfoodsecurity.

Thefishingsectorshouldstrivetoloweritsfuelconsumption, reduceitscarbonfootprint,anddecreaseecosystemimpacts.To achievesignificantandpermanentreductions,governmentswill needtostrengthentheirfisheriessectorenergypolicyandcreate anenablingenvironmentinwhichfishingsectorcanrapidlyand comprehensivelyadoptLIFEfishingtechnologiesandpractices.The developmentandadoptionofLIFEfishingtechniquesofferscopefor maintaininglongtermprofitabilityandsustainability.

Excessiveuseofanygeartype,evenlow-impactgear,maycause overexploitationandecosystemimpactsiftotalfishingeffortistoo high.Therefore,withoutbeingpartofaneffectivefisheries manage-mentsystem,animprovementinfuelefficiencywillnotnecessarily leadtoasustainedreductioninthetotalfuelconsumptionbecause higherreturnsmayattractnewentrantsintothefishery.The adop-tionofLIFEfishingtechniquesshouldthereforebeseenasoneofthe strategiesthatcanbeusedtoimprovetheoutcomesforafishery thatisoperatingwithinanEAFbasedmanagementsystem.

Globalresearchanddevelopmentprioritiesshouldbe estab-lishedwithworkundertakentosupportdevelopmentanduptake ofLIFEfishing.Theseinclude(1) promotingandfundingstudies ofcost-effectivegeardesignsandfishingoperations,includingthe establishmentoftechnologyincubatorsandotherpublic–private sectorinitiativestocommercializeeconomicallyviable,practical andsafealternativestoconventional fishingmethods,(2) anal-ysisand review ofbest practiceoperations acrossfisheries, (3) improvementoftechnicalabilityamongfishers,(4)establishment

ofappropriateincentives,and(5)executionofrobustbutflexible fisherymanagementpoliciesthatsupportthetransitionto alterna-tivetechnologies.Closecooperationbetweenthefishingindustry, scientists,managersandotherstakeholderswillbenecessaryto enablethedevelopmentandintroductionofLIFEfishing technolo-gies.

Giventhatfishingisacomplexsystem,changingonevariable canhave aripple effectonothervariables and theaffectsmay notchangeinalinearmanner.Therefore,changingonevariable maynotnecessarilyachievethedesiredorexpectedoutcome.As wemovetoaddressthenumerousenvironmentalandcommercial problemsfacingfisheries,weneedtotakeacomprehensiveand holisticapproachand notindependentlyfocus ona singlefacet ofthemanydriversthataffectfisheryperformance.Clearly,the optimalsolutionswillvaryamongfisheries.

Acknowledgements

The authors incorporated valuable advice from Kevern Cochrane,RickFletcher,DonGunderson,DuncanLeadbitter,Robert LeeandRolfWillmann.Theauthorsalsoappreciatethe prepara-tionoffishinggearillustrationsbytheSoutheastAsianFisheries DevelopmentCenter(SEAFDEC).

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