A review of bycatch and discard issues in Indian Ocean tuna fisheries

TABLE OF CONTENTSABSTRACT........................................................................................................... 5

1. INTRODUCTION.............................................................................................. 11

2. DEFINITIONS AND CONCEPTS..................................................................... 15Issues related to target catch........................................................................... 16

Yellowfinandbigeyetunasinsurfacefisheries........................................ 16 Fishsizesbygear..................................................................................... 17

3. INDIAN OCEAN TUNA FISHERIES INCLUDED IN THIS STUDY................... 19

4. IOTC RESOLUTIONS – THE REGULATORY FRAMEWORK........................ 21Stockstatusoftargetandbycatchspecies...................................................... 22

The“targetspecies”.................................................................................. 22 Neritictunasandbillfish............................................................................ 22 Otherfinfish.............................................................................................. 22

Shark status.................................................................................................. 22 Blue sharks............................................................................................... 23 ShortfinMakosharks................................................................................ 23 OceanicWhitetipshark............................................................................ 23

5. BYCATCH AND DISCARDS IN TUNA FISHERIES......................................... 27Pole-and-line,includingtheirassociatedbaitfishery....................................... 27Longline........................................................................................................... 27Asian tropical and temperate tuna longline..................................................... 27Bycatchdatareportedbylonglinefleet........................................................... 28

Japan....................................................................................................... 28 Korea....................................................................................................... 29 Taiwan..................................................................................................... 29 China....................................................................................................... 29 Indonesia................................................................................................ 30

SpanishandPortugueseswordfishlongline.................................................... 30Frenchswordfishlongline................................................................................ 31SouthAfricanlongline...................................................................................... 31EstimatedtotalBluesharkandShortfinMakocatches.................................... 32Depredationinlonglinefisheries...................................................................... 32Baituse............................................................................................................ 32Theeuropeanpurseseinefishery.................................................................... 32TheeffectofPiracyonpurseseinefisheries................................................... 36Driftgillnetfisheries.......................................................................................... 37

6. MITIGATION..................................................................................................... 39Pole-and-line.................................................................................................... 39Longline............................................................................................................ 41Substitutionofpole-and-lineforpurseseinefisheries..................................... 42

Pole-and-linetrialsintheIndianOcean.............................................. 42 Carbonfootprintoftunafisheries......................................................... 43

7.CONCLUSIONS............................................................................................... 45Stock status.................................................................................................. 45Bycatchanddiscards................................................................................... 45Mitigation...................................................................................................... 46

Pole-and-line......................................................................................... 46 Purseseine........................................................................................... 46 Longline............................................................................................... 46

Otherecologicalissues................................................................................ 47Enforcementandverification....................................................................... 47Closingcomments........................................................................................ 47AppendixI………………………………………………………………………... 55

SmartFishProgrammeReport SF/2013/32 5

ABSTRACTPublicawarenessandconcernover theenvironmental impactof foodproductionandsecurity is risingrapidly.Whetherrealorperceived,scientificallyjustifiedorcompletelyfalse,theseperceptionscanshapefisheriesbyinfluencingmarketing,demandandproductflow.Inthefisheriessector,impactscanincludeoverexploitation of both target and non-target stocks, damage caused to the environment by lost ordiscardedfishinggear,“ghostfishing”andpollutioncausedbydiscards,aswellasthe“carbonfootprint”of fishingandbaitingoperations. Themost recentestimatesofnon-target,associatedanddependentspecies(NTAD)takenbyglobalfisheriesisof7.3milliontonnesannually,63%ofwhichresultsfromtrawlfisherieswithonly5%ofthetotalfromalltunafisheriescombined.

Thereisgeneralagreementthatthislevelofwasteisunacceptable.Furthermore,althoughretainednon-targetcatchmayberecordedandreportedtoflagstateauthoritiesandRegionalFisheriesManagementOrganizations(RFMOs),notrackisusuallykeptofdiscardsofdeadorganisms,whetherornotoftarget-species,resultinginwastageanddistortionsofdatasetsusedforstock-assessments.Acleardistinctionshouldthereforebemadebetweenbycatchanddiscards.

Thisstudy,basedonofficialstatisticsandpublishedmaterial,concentratedonpole-and-line,purseseineandlonglinetunafisheriesoftheIndianOcean,which,althoughrepresentinglessthanhalftheregion’stunalandings,aretheonlysectorshavingsufficientstatisticaldataandgovernancetopermitanalysisandtheapplicationofmitigationmeasures.Somenewinformation isalsopresentedondriftgillnetfisherieswhichhavemorecatchthantheotherfisheriescombinedandresultinhighlevelsofbycatch.Itshouldbenotedthat,whileoftenhavingsignificantnon-targetcatch,artisanalfisheriesrarelydiscardandfullyutilizetheirretainedcatch.VariousNon-governmentalorganizations(NGOs)haveembarkedonmediacampaignsanddirectaction,pressuringmarkets to source surface tunafisheryproducts frompole-and-lineandFAD1 -free sourcesalone.

NTADfishingmortalityanddiscardingpracticesare reviewedhere frompole-and-line,purseseineandlonglinefisheriesintheIndianOceantoestablishtheenvironmentalimpactofeachfishery.Wherepossible,measurestomitigateunwantedNTADmortalitiesareproposed.

The target species of the surface fisheries are skipjack, yellowfin and bigeye tunas. In the longlinefishery,thelattertwospeciesarejoinedbyalbacore,swordfish,andnowbybluesharksforsomefleets.Managementof tunafisheries isunder the responsibilityof the IndianOceanTunaCommissionwhichhasdeterminedthatnoneofthetargetspeciesofthesurfacefisheryareatpresentoverfished,althoughthelevelofexploitationofalbacorebythelonglinefisheryisunsustainable.Skipjackishoweverthemostrobuststock, theother two tropicaloceanicspeciesbeing longer livedandslowermaturing, thusmorevulnerabletooverexploitation,withpossibleinteractionsbetweensurfaceandhighvaluelonglinefisheries.

Thefree-schoolpurseseinefisheryhasbyfarthelowestbycatch(1.7%),butwithonly20%skipjack,themostrobustspeciesand80%yellowfinandbigeyetunawhicharemoresensitivetooverfishing.Skipjackcatches rise to 61% in the FO2 purse seine fishery, but with 5.3% bycatch. In the two fishingmodescombined,thebycatchlevelis3.55%,54%ofwhichwereneritictunasandalbacore.Nobycatchspeciesarethreatened,andthetonnageofeachistoosmalltoimpactstocks.PiracyhaschangedfleetoperatingpatternstowardsFOdirectedeffort.Anumberofmitigatingmeasuresarebeingstudiedinthecontextofthe EU-MADE4andISSF5projects.

1. FishAggregatingDevicesareusedtoconcentrateandholdfishinseasonswhenpurseseiningwouldnotnormallybepossibleintheabsenceofawell-definedthermocline.

2. FloatingObject;includesvirtuallyanythingfloatingatornearthesurfacethatcanaggregatetuna3. Mitigatingadverseimpactsofopenoceanfisheries4. InternationalSustainableSeafoodFoundation

SmartFishProgrammeReportSF/2013/326

Inthepole-and-linefishery,skipjackwithsomeyellowfinandbigeyetunasmakeup87%andbycatch4.3%andbait8.3%oflandings.Asinthepurseseinefishery,mostofthebycatch,largelyneritictunas,iscannedforlocalconsumptionorconsumedfresh.Inaddition,thefuelusedbypole-and-linefleetsisestimatedtobetwicethatofpurseseinefisheriespertonneofcatch.

BycatchandofdiscardsintheIndianOceantunafisheriesfromlonglinefisheriesishigherthanforothergears,exceptforgillnets.Baitusedinthefishery,whichcanbeconsidereda“discard”,amountstohalfthetotalcatch.Bycatchconsistsof87speciesorspeciesgroups,includingsharks,seabirdsandturtles,manyofwhicharelistedbytheInternationalUnionfortheConservationofNature(IUCN)asbeingthreatenedorendangered.Mitigationmeasuresappeartohavereducedseabirdmortalityintemperatewaters,butinthosefleetsnottargetingsharks,theactualsharkcatchwasprobablyuptothreetimesthatreported.

ThePortuguesefleetthatutilizeswireleadersrecordshighmortalitylevelsofblue,mako,silky,whitetipand threshersharkswhile75%ofbluesharksandmost raysappears tosurvive.TheFrance-Réunionfleetwhichusesmonofilamentnylon leadersregistered80%reduction in thenumberofsharkscaught.Mitigationmeasurescouldthusincludemandatingtheuseofnylonleaders inthosefleetsnottargetingsharks.

Othermitigationmeasuressuggestedincludefullcatchretention,whichwouldimprovefoodsecurityandnutrition incoastalcommunitieswherebycatch is landedandmandatorymonitoringof tunavesselsviaobserverprogramsorremotesensingdevices.

The potential to replace floating object-associated purse seine catches by pole-and-line or FAD-freeproductionisalsoexamined.AtotalbanonFOsetsinthepurseseinefisheryisnotseenasaviableoptionasitmightresultinthepurseseinefleetleavingtheIndianOcean,withdisastrousconsequencestotheeconomiesofcoastalcountriesprovidingservicestotheindustryandprocessingfish,aswellasmassivelossofemployment.Substitutingpole-and-lineproductionforpurseseinewouldactuallyresultinasixfoldincreaseincatchofnon-targetspeciesanddoublingthefuelusedinthefishery.Finally, lackofbaitfishstocksandhumanresourcesexperiencedwiththepole-and-linemethod,aswellasofinvestmentcapitalareseenasmajorbarrierstotheexpansionofthepole-and-linefishery.Realistically,landingsbypole-and-linewillneverbeabletosupplythevolumeofrawmaterialsthatpurseseineproducesforthecanningindustry.

ThisstudyconcludesthattheIndianOceantunafisheriesdiscussedinthispaperhaveaverylowlevelofbycatch,particularlyincomparisonwithothergeartypesfisheries.Thelevelofdiscardingalsoappearstobenegligible,otherthanthatofsharksinsomelonglinefleets.

AmajorexceptionarethenorthernIndianOceandriftgillnetfleetswhich,althoughdatadeficient,appeartohavebycatchofecologicallysensitivespeciesordersofmagnitudehigherthanthatoftheothergears,tosuchanextentthatthebycatchfrompole-and-line,purseseineandevenlonglinesisprobablyinconsequential.


RÉSUMÉLepublicestdeplusenplussensibleà lasécuritéetaux impactsenvironnementauxde laproductionalimentaire.Qu’ellessoientréellementvécuesousubjectives,scientifiquementjustifiéesoucomplètementfausses,cesperceptionsfaçonnentlespêcherieseninfluençantlacommercialisation,lademandeetlesfluxdeproduits.Danslesecteurdelapêche,lesimpactsincluentlasurexploitationdestocksciblésounon-ciblés, lesdommagescausésà l’environnementpar laperteou l’abandond’enginsdepêches (lapêche fantôme)et lapollutioncauséespar les rejets,ainsique l’empreintecarboneoudesopérationsdepêche.Lesestimationslesplusrécentesdesespècesnonvisées,associéesetdépendantes(NVAD)capturéesparlapêchemondialesontà7,3millionsdetonnesannuelles,dont63%résultentdelapêcheauchalut,etseulement5%dutotalincombeàl’ensembledespêcheriesdethon.Il est communément admis qu’un tel niveau de gaspillage est inacceptable. En outre, même si desprises non-ciblées peuvent être enregistrées et reportées auprès des autorités de l’Etat du pavillon etauxOrganisationsRégionalesdeGestiondesPêches (ORGP),engénéralaucune tracedes rejetsetorganismesmorts-quecesoitounondesespècescibles-n’estgardée,cequisetraduitparungaspillageetunedistorsiondesdonnéesutiliséespourl’évaluationdesstocks.Unedistinctionclairedevraitdèslorsêtrefaiteentrerejetsetprisesaccessoires.

Baséesurdesstatistiquesofficiellesetautrespublications,cetteétudes’estconcentréesurlescanneurs,lessenneursetlespalangriersciblantlethondansl’OcéanIndien.Cessecteurs,bienquereprésentantmoinsdelamoitiédesprisesdethondelarégion,sontlesseulssecteursàdisposerdesuffisammentdedonnéesstatistiquesetdegouvernancepourpermettrel’analyseetl’applicationdemesuresd’atténuation.

Denouvellesinformationssontégalementprésentéesausujetdelapêcheaufiletmaillantdérivant,quireprésentedavantagedecapturesquelesautrespêcheriesthonièrescombinéesetaffichedesniveauxdecapturesaccessoirestrèsélevés.Ilfautnoterque,bienquesouventàl’originedenombreusescapturesnon-ciblées, les pêcheries artisanales engendrent rarement des rejets et utilisent l’entièreté de leurscaptures.

DesOrganisationsNonGouvernementales(ONG)ontréalisédescampagnesmédiatiquesetdesactionsdirectesafind’exercerunepressionsurlesmarchéspourqu’ilsnes’approvisionnentqu’enthonspêchésensurfaceissusdecanneursousansl’emploiedeDCP1.

LamortalitédepêchedesespècesNVADetlespratiquesderejetdescanneurs,senneursetpalangriersdel’océanIndiensonticipasséesenrevue,afindedéterminerl’impactenvironnementaldechaquepêcherie.Lorsquec’estpossible,desmesurespourminimiserlamortalitédesNVADsontproposées.Lesespècescibléesparlespêcheriesdesurfacesontleslistaos,lesalbacoresetlesthonsobèses.Danslapêcheàlapalangre,àcesdeuxdernièresespècess’ajoutentlegermon,l’espadonetdésormaislerequinbleupourcertainesflottes.LagestiondespêcheriesthonièresestsouslaresponsabilitédelaCommissionThonièrede l’Océan Indien, qui estimequ’aucunedesespèces ciblesde la pêcherie de surfacen’estsurexploitée,bienqu’actuellement ledegréd’exploitationdugermonpar lapêcheà lapalangrenesoitpasdurable.Cependant,leslistaosreprésententlestockleplusrobuste,puisquelesdeuxautresespècestropicalesocéaniquesviventplus longtemps,atteignent leurmaturitéplus lentement,etsontdoncplusvulnérablesàlasurexploitation,avecdepossiblesinteractionsentrelapêchedesurfaceetlapêcheàlapalangre,àplushautevaleur.

Lapêcheàlasennesurbancslibresadeloinletauxleplusfaibledecapturesaccessoires(1,7%),maisavecseulement20%delistaos,l’espècelaplusrobuste,et80%dealbacoresetthonsobèsesquisontlesespèceslesplussensiblesàlasurpêche.Lepourcentagedecapturedelistaosgrimpeà61%danslapêcheàlasennesurobjetsflottants2,avecseulement5,3%decapturesaccessoires.Encombinantles

1. LesDispositifsdeConcentrationduPoissonsontutiliséspourconcentreretcapterlespoissonspendantlessaisonsdurantlesquellesilneseraitnormalementpaspossibledepêcheràlasenne,enl’absencedethermoclinebiendéfinie.

2. Lesobjetsflottantsincluenttoutcequiflottesurouprochedelasurfaceetquipeutrassemblerlethon.


3. Mitigatingadverseimpactsofopenoceanfisheries4. InternationalSustainableSeafoodFoundation

deuxmodesdepêche,lescapturesaccessoiress’élèventà3,55%,dont54%sontdesthonsnéritiquesetdesgermons.Aucuneespècedepriseaccessoiren’estmenacée,et les tonnagesdechacunesonttropminimespourimpactersurlesstocks.Lapiraterieachangélesschémasd’opérationdesflottesenorientantl’effortverslespêcheriessurobjetsflottants.Uncertainnombredemesuresd’atténuationontétéétudiéesdanslecontextedeprojetsdel’UE(MADE3)etdel’ISSF4.

Danslapêcheàlacanne,leslistaos,lesalbacoresetlethonobèsereprésentent87%desdébarquements,tandisquelesprisesaccessoiresreprésentent4,3%etlesappâts8,3%.Toutcommedanslapêcheàlasennecoulissante,laplupartdesprisesaccessoires–enmajoritédesthonsnéritiques–sontsoitmisesenconservepour laconsommation locale,soitconsomméesfraîches.Deplus, lecarburantnécessaireàlapêcheàlacanneestestiméaudouble–partonnedeprise–deceluinécessairepourlapêcheàlasennecoulissante.

Les prises accessoires et rejets observés dansla pêche au thon dans l’océan Indien sont plusnombreux dans la pêche à la palangre que dansles autres types d’engins, à l’exception des filetsmaillants.Lesappâtsquisontutilisés,etquipeuventêtreconsidéréscommedesrejets,comptentpourlamoitiédescapturestotales.Lesprisesaccessoiressont constituées de 87 espèces ou groupesd’espèces,incluantlesrequins,lesoiseauxdemeretlestortues,dontbeaucoupsontrépertoriéesparUnion Internationale pour la Conservation de laNature(UICN)commeétantdesespècesmenacéesou en danger. Certaines mesures d’atténuationsemblentavoirpermisderéduireletauxdemortalitédesoiseauxdemerdansleseauxtempérées,maisdanslesflottesneciblantpaslesrequins,lespriseseffectivesderequinsétaientprobablementtroisfoissupérieuresàcequiétaitdéclaré.

Laflotteportugaisequiutilisedesbasdeligneenacieraenregistrétauxdemortalitéimportantspourlesrequinsbleus,requins-taupes,requinssoyeux,requinsocéaniquesetrequinsrenardsretournésàl’eau,alorsque75%desrequinsblancsetdesraiessemblentsurvivre.LaflottedeLaRéunion(France),quiutilisedesbasdeligneennylonmonofilament,a enregistré une diminution de 80% des prisesde squales. Lesmesures d’atténuation pourraientdonc rendre l’utilisation de bas de ligne en nylonobligatoirespourlesflottesneciblantpaslerequin.

Parmilesmesuresd’atténuationsuggérées,oncomptelarétentiondetouteslesprises–cequiamélioreraitlasécuritéalimentaireetnutritionnelledescommunautéscôtièresoùlesprisesaccessoiressontdébarquées–etlesuiviobligatoiredesthonierspardesprogrammesd’observationoudesdispositifsdetélédétection.Lepotentielquereprésenteleremplacementdessenneurspêchantsurobjetsflottantspardescanneursoud’autrestypesdeproductionn’impliquantpasl’usagedeDCPestégalementexaminé.L’optiondebannirtotalementlesprisessurdispositifsflottantsdanslapêcheàlasennen’estpasjugéviableétantdonnéquecelapourraitamenerlaflottedesenneursàquitterl’océanIndien,avecdesconséquenceséconomiques


désastreusespour lespayscôtiersquisontpourvoyeursdeservicespour l’industrieet transforment lepoisson,ainsiqu’unepertemassived’emplois.Substituerlaproductiondescanneursàcelledessenneursauraitpoureffetdemultiplierparsixlesprisesaccessoiresetdedoublerlaconsommationdecarburant.Enfin,unmanquedestocksd’appâtsetderessourceshumainesexpérimentéesdanslaméthodedelapêcheàlacanne,ainsiqu’uncapitald’investissementinsuffisant,sontvuscommelesobstaclesmajeursàl’expansiondelapêcheàlacanne.Defaçonréaliste,lesdébarquementsdescanneursnepourrontjamaisfournirlevolumedematièrepremièrequelapêcheàlasenneproduitpourl’industriedelaconserve.

Cetteétudeconclutquelespêcheriesthonièresdel’océanIndiendiscutéesiciontuntauxtrèspeuélevédeprisesaccessoires, particulièrement quandon les compareàdespêcheriesutilisant d’autres typesd’engins.Leniveauderejetsestégalementnégligeable,àl’exceptiondesrequinscapturésparcertainesflottesdepalangriers.

L’exceptionmajeuresesituedanslenorddelarégion,oùlapêcheauxfiletsdérivantssemble–malgrélemanquededonnées–donnerlieuàdavantagedeprisesaccessoiresd’espècesécologiquementsensiblesencomparaisonàd’autresengins,àtelpointquelesprisesaccessoiresrésultantdelapêcheàlacanne,delapêcheàlasenneetmêmedelapêcheàlapalangresontcomparativementnégligeables.


1

Introduction


Publicawarenessandconcernovertheenvironmentalimpactoffoodproductionandsecurityisrisingrapidly.Whetherrealorperceived,scientificallyjustifiedorunfounded,theseperceptionscanshapefisheriesbyinfluencingmarketing,demandandproductflow.Inthefisheriessector,impactscanincludeoverexploitationofbothtargetandnon-targetstocks,damagecausedtotheenvironmentbylostordiscardedfishinggear,“ghostfishing”andpollutioncausedbydiscardsor,inaquaculture,unconsumedfeedandwasteproducts,aswellasthe“carbonfootprint”offishingandbaitingoperationsandsocio-economicelements,notablyindevelopingcoastalcountries.

Intheseminalpaperonthesubjectofbycatch,Alversonetal.(1994)estimatedthatanaverageof27milliontonnes(t)offishwere“discarded”annually,equivalentto30%oftheworldfishlandings,althoughthereportstatedthatsomeofthisfishmayhavebeenlandedandconsumed5. Levelsofbycatcharenowbelievedtobefallingandhavebeenestimated(usingadifferentmethodology)at7.3milliontonnesannuallybetween1992and2001(Kelleher,2004)6.

Whateverthelevelsare,thereisgeneralagreementthattheselevelsofwasteisunacceptable.Furthermore,althoughretainednon-targetcatchmayberecordedandreportedtoflagstateauthoritiesandRFMOs7,notrackisusuallykeptofdiscardsofdeadorganisms,whetherornotoftarget-species,resultingindistortionsofdatasetsusedforstock-assessments.

Drivenbytheseconcerns,NGOs8haveembarkedinpublicityanddirectactionaimedatconsumersandfishbuyersinEuropeadvocatingthatcoastalstatesdevelopdomesticpoleandlinefisheries,whichhavethepotentialtobethemostenvironmentallyfriendlymethodoffishingskipjack,condemningpurseseining,inparticularonFishAggregationDevices(FADs)(Stoneetal2009).TheelementscitedbyenvironmentalNGOsinclude:

1. SkipjackarefullyexploitedintheIndianOcean;

2. BycatchfromFADsisunsustainable(includingturtles,sharksandjuvenilesofyellowfinandbigeyetuna;

3. Distantwatertunafishingfleetsprovidelittleeconomicorsocialbenefitstocoastalstates(amere6%ofvalueoftunacaughtincoastalwaters);

4. Poleandlinefisherieshavethepotentialtobethemostenvironmentally-friendlymethodoffishingskipjackifmanagedcorrectly.Asthefisharecaughtone-by-one,theoperationcanbestoppedatanystageifundersizedfishgethooked.

5. Thequalityofpoleandlinecaughtskipjackisalsomuchhigherthanthatoffishcaughtusingothermethods,aseveryfishcaughtisbroughtonboardalive.

5. Thepaperdidpointout,however,thatpelagicpurseseineshadrelativelylowlevelsofbycatch.6. 63%fromtrawlfisheriesandonly5%fromtunafisheries7. RegionalFisheriesManagementOrganizations8. Non-governmentalOrganizations

1. INTRODUCTION


6. TheaveragecostofproducingatonoftunacaughtwithpoleandlineintheEasternPacificisabouthalftheaveragecostofproducingatonoftunacaughtbyapurseseinerintheEasternPacific;

7. Forcoastalstates,poleandlinefisheriesalsooffergreateremploymentopportunities;

However,thesamereportstatesthat:

8. Poleandlineiscomprisedoftwointerlinkedfisheries;oneforlivebaitandonefortuna.Thetargetspeciesofpoleandlinefisheriesareskipjack,albacoreoryellowfintuna.Inskipjackfisheries,between70-100%ofthefinalcatchisthetargetspecies.Mostoftheremainingcatchisotherspeciesoftuna,includingjuvenileyellowfin,whichismostlykeptonboardandusedforlocalconsumption.

9. Anecdotaldiscussionssuggestthat70-80%oftheskipjackintheMaldivesisnowcaughtaround anchored FADs.

Thenewly-createdIPNLF9states:“Pole-and-lineisregardedasthemostresponsiblewaytofishtuna”.and“[Large-scaleindustrialfleets]providelittleopportunityforemploymentandrevenueflowstolargeenterprises–nottofishingcommunities.10” and“Ourstrategyisclear:engagetheglobalmarketstosupportprocuringandsourcingfrommoreequitableandsustainabletunafisheries...”

Thecurrentstudy,basedonofficialstatisticsandpublishedmaterial,examinesthepotentiallynegativeecologicalimpactsofthedifferentexport-orientedtunafisheriesintheIndianOcean,bothinabsolutetermsandincomparisonwithotherfishingactivities.ItalsoexaminespotentialmeasurestomitigatetheseimpactsandcomparestheassertionsofNGOslistedabovewithverifiablesources.

9. InternationalPole-and-lineFoundation10. DatafromtheIndianOceanCommissionMCSproject placedrevenuetothewesternIndianOceanislandsat €500millionannuallyandemploymentinserviceindustries atsome30,000full-andpart-timejobs.

Introduction



2

DefinitionsandConcepts


Thevarioususesoftheterm“bycatch”causeconsiderableconfusion.Inadditionto“bycatch”havingseveralmeanings,thereistheadditionaldifficultyofapplyingtheconcepttosmall-scalefisheries.“Bycatch”and“targetcatch”canberelativelyclearinlarge-scalefisheriesofdevelopedcountrieswherethereisanobjectiveofcapturingfishforparticularmarketchains,buttheseconceptsbecomeincreasinglyirrelevantintheprogressiontosmall-scalefisheriesindevelopingcountrieswherealmosteverythinginthecatchhaseconomicorsubsistencevalueandcanbecomeatarget(Gillett,R.2011).Manyofthesmall-scalefisheriesthatcapturetuna,aretrulymulti-species–withthe“target”beingalmostanytypeoffish.Alternatively,forsomeoftheotherfisheriescoveredinthisreport,therearespecifictargets,buttheyarenottuna(i.e.tunacouldbeconsideredabycatch).

Theword“bycatch”inthecontextofthisstudyincludesnon-targetmarineorganisms(non-targetfin-fish,cetaceans,seaturtles,sharks,etc.),whetherretainedandsoldordiscarded (bycatch or incidental catch).Bycatchisafeatureofvirtuallyallfisheriesandcansometimesbemitigated,butnottotallyavoided.Incertaincircumstances,notablymostsmall-scalefisherieswhereallthecatchisconsumed,retainedbycatchmayhaveahighvalue.

Discardsareaperniciousformofbycatchastheyrepresentawasteofediblefish.Moreover,discardedorganismsarevirtuallyneverreportedintheabsenceofobservers,whichresultsinadistortionofdatausedinstockassessment.

Thesediscardsgenerallyconsistof:• specieswhichcannotbemarketedorforwhich

aviablemarketdoesnotcurrentlyexist:

- sharks,rays,triggerfish,seabirds,etc.- tuna-likespeciesforwhichamarketdoes

notexistforthefishery(kawakawa,frigate,bullettunas)

- pooranticipatedshelflife(egdolphinfishwhichspoileasily)orfromsaltcontaminationinseinerwells

- baitfishandaccidentalcatchesofassociatedspecieswhilebaitfishing

• targetspecies- sizestoosmallforthemarkets- heavymetalcontaminantsatlargesizes

(egswordfish)- crushedbythegear- spoiledduetolongimmersioninthesea

afterdeath- depredationdamage(predationbysharks,

cetaceansorsquid)- discardedduetolackofstoragespaceat

theendofatrip- discardedthroughthepracticeof“high-

grading”,particularlyinquota-managedfisherieswhereonlythe highestvaluefishareretained11.

Thenotionofdiscardsiscomplicatedfurtherbythefactthatsomeorganismssuchaslargesharks,marineturtlesandcetaceansareusuallyreleasedaliveandfrequentlysurvive.Whileobserversroutinelyrecordtheseoccurrences,mostlogbookformatsdonotpermitthisdistinctionandscalesforconditionfactorarenotstandardized.Thereisalsoashortageofstudiesthatactuallytrackordocumentpost-releaseconditionofdiscardsthroughtheuseofsatellitetagsorobservationinpost-releaseconfinement.

Issuestoconsiderinrelationtobycatchinclude:

11. Longlinersroutinelydiscardtunaswhicharetoosmallforthesashimimarket(highgrading).Thesevesselsusedtodiscardbillfishaswell,butrarelydosonowasthevalueofthesespecieshasrisen.

2. DEFINITIONS AND CONCEPTS


Theprincipaltargetofpole-and-lineandpurseseinefisheriesistheskipjacktunathatistheprimaryrawproductforcanning,alsousedbytheMaldiviansandJapaneseforspecialtydriedproducts.Thestocksaregenerallyconsideredtobe“robust”inthatthespeciesisfast-growing,reproducinginthefirstyearwithrapidturnover,arewidelydistributedandaccessibleinhighvolumeintropicalandsub-tropicalwatersofalltheoceans.

Someauthorsconsiderbigeyeandtoalesserextentyellowfintunasasa“bycatch”ofthesurfacefisheries(e.g.therecentassessmentforMSCoftheMaldivesskipjackpole-and-linefishery).Thesespeciesarelongerlived,reproducelaterandarethusmoresusceptibletoover-exploitation.Thesetwospeciesarealsotargetedbylonglinefisherieswhentheyhaveafarhighervalueinthesashimimarkets.Thereisthusanissueofinteractionbetweenthelonglineandpurseseinefisheries.Finally,thecaptureofsmallfishcancontributeto“growthoverfishing”andtoareductionofthereproductivepotentialofthestocks.

(a) Isthespeciestrulythreatenedorendangered(orthesubjectofparticularconcernsuchascetaceans,marineturtles,sharksandseabirds)?

(b)Willreductionofthespecieshaveknock-onecologicaleffects(negativeorpositive)?

(c) Whatuseismadeofthelandedbycatch?(d) Whatmeasurescouldbetakentoreduce

bycatch(includingexploitingthetargetspecieswithotherfishingmethods)?

Issues related to target catch

Thetermtarget catchisusedhereonlyasadescriptorofthedifferentfisheries,astargetingofparticularspeciesisevolvingasnewmarketsaredevelopedand“retainedbycatch”isnowvirtuallyallconsumed,oftendistributedfree12aftersortingwhenlanded.Twoissuesremain,however,relatedtothesizeoffishinthecatches.

Yellowfin and bigeye tunas in surface fisheries

Figure 1: Free- and associated-school species composition, 2010 (IOTC)

12. Incertaincases,freedistributionofbycatchhasundercutthetraditionalmarketsofsmall-scalefisherswithundesirablesocialeffects,eventhoughfoodsecuritymayhavebeenenhanced.

Free-schoolpurseseinespeciescomposition

Figure1:Free-andassociated-schoolspeciescomposition,2010(IOTC)

Associated-schoolpurseseinespeciescomposition

DefinitionsandConcepts


However,free-schoolpurseseinesetscatchlessthan20%skipjackintheIndianOcean13 (Figure1)andthereisthuslittlejustificationforconsideringthesetwospeciesasnotformingpartoftargetcatch14,althoughtheremaybeacasetoconsiderspecificmitigationmeasurestolimittheirexploitationinsurfacefisheriesbecauseofgrowthoverfishingandthefisheryinteractionsidentifiedabove.

Furthermore,inpurseseineFO15setsandinpole-and-linecatches,thecontributioninweightofthepredominantlyjuvenilefishismodest,whiletheremovalsinnumbersatsizeswherenaturalmortalityisfallingmighthaveadisproportionateeffectonstockstatus16(Figure2).

Observersreportedthatleast15%ofthetargetspeciesareunderthecommercialsizeof40cmFL(Amandéet al.2008)whichdonotenterthecannerytradeintheIndianOcean,butseinerskippersnowtrytoavoidsettingonsuchsmallfish,notleastbecauseofthepossibilityofmeshinginthenetsandthelossoffishingtimefromcatchingandreleasingunwantedfish.

Figure 1: Species and size composition in Indian Ocean purse seine FAD catches 2000-

2006 (Fonteneau, 2007)

13. TherelativeabundanceofSKJ,YFTandBETvariesconsiderablybyoceanarea,soYFTisasignificantpartoftheIOandEPOcatchforexamplebutlesssoforWPO.BETalsovariesalotandcanbeasignificantpartofthecatchinsomeareasbutverylittleinothers.

14. TheIOTCWorkingPartyonEcosystemsandBycatchdefinedbycatchas:“allspeciescaughtinIOTCfisheriesotherthanthe16spe-ciesoftunaandtuna-likespeciesthatarelistedintheIOTCAgreement”.

Assuch,noneofthesespecieswouldbeclassedas“bycatch”.15. FloatingObjects:includeFADs,driftwoodandotherflotsam,deadcetaceans,whalesharksandseamounts.16. Ithasbeenestimatedthat70%ofBETin numbersiscaughtbypurseseinefisheries(IOTC).17 Sharp(pers.com.)suggestedthatskipjackassociatedtocoastalareashaveaslowergrowththanthoseinvolvedintrans-oceanic

migrations.

Fish sizes by gear

Figure3belowshowstheevolutionofthesizescaughtbyvariousgears:

Purseseinefisheriescatchthewholerangeofsizesbetween40and70cmFL,whereaspole-and-linecatchesshowtwomodes,below50cmandabove60cmFL17.Aspole-and-lineproductionisaboutonethirdthatofpurseseineproduction,itappearsthattheproportionofsmallfishisgreaterfromthisfishery.

Figure 1: Fish sizes by gear and year

Figure2:SpeciesandsizecompositioninindianOceanpurseseineFADcatches2000-2006(Fonteneau,2007)

Figure3:Fishsizesbygearandyear

3

IndianOceanTunaFisheriesIncludedinthisStudy


IndianOceantunafisheriessupportawiderangeofeconomicactivities.Artisanalfishingisasignificantcontributortoemploymentandnutrition,whilelarge-scalefishingisassociatedwithrevenuederivedfromforeignfishingaccess,onshoreprocessingandpaymentsforsuppliesandportfees.ThetotalvalueofthetunacatchintheIndianOceanisnotwellunderstood.Severalestimatesofthelandedvalueofthecatchareintherangeof€1.5to3billion,withtherelativelyhighpricespaidforartisanalcatchesamajorfactorinthelargeover-allvalue.

MorethanhalfIndianOceantunacatchesaremadebysmall-scalegears.Handline,troll-lineandringnetfisheriesareartisanalgearscatchingtunasandarealsonotconsideredfurtherbecauseofthelackofreliablebycatchdata.Itshouldbenoted,however,thatartisanalfishersrarelydiscard“non-target”catches,whichareallconsumed.

Thelargesttunacatchbygearisnowfromdriftnetfisheries,whichnowreportcatchesofmorethan650,000t(IOTC18NominalCatchdata)19. Driftnetsofmorethan2.5kminlengtharebannedbydecisionoftheUNGA,buttherearevirtuallynocontrolsonthe3,000vesselsusingthisgear(Fonteneau,2011).AnotherdifficultyintryingtogaugetheseverityoftheimpactofgillnetsonspeciesofspecialconcernintheIndianOcean,aswellasinotherregions,isexpressedbyNorthridge(1991):“Formostofthegillnetfisheriesofthe

world,informationoncatchratesistoopoortomakeanyreasonableestimateoftotalcatchesofnon-targetspecies”.Inthe8thSessionoftheIOTCWorkingPartyonEcosystemsandBycatch(WPEB)someinformationwasmadeavailableongillnetfisheriesofIran,SriLankaandPakistan.Inthefirstcase,thedatacamefromlogbooksfilledby75vessels,whileintheothertwocountriesthedataarefromsamplingoflandings.AnothersourceofinformationisfromISSFTechnicalReport2012--05,AreviewofbycatchintheIndianOceangillnettunafleetfocussingonIndiaandSriLanka,(MRAG,2012).

Whilenotcomprehensive,thesedataareincludedinthisstudyforcomparativepurposes.

Thefollowingfisheriesforwhichthereissufficientdataforstudyareallorientedtowardstheinternationalexportmarkets:

1. TheMaldivespole-and-linefishery,includingtheassociatedbaitfishery;

2. Longline:2.1.Asiantropicalandtemperatetuna longline;2.2.SpanishandPortugueseswordfish longline;2.3.Frenchswordfishlongline;2.4.SouthAfricanlongline;2.5.Indonesianlongline.

3. Europeanpurseseine

18. IndianOceanTunaCommission19. About25%ofthetotalcatchofyellowfin,bigeye,skipjack,andswordfishismadebybygillnetsintheIndianOcean

3. INDIAN OCEAN TUNA FISHERIES INCLUDED IN THIS STUDY


4

IOTCResolutions–TheRegulatoryFramework


ManagementofIndianOceantunasisundertheresponsibilityoftheIndianOceanTunaCommission(IOTC)20.UndertheprovisionsofUNCLOSandofitsFishStocksAgreement21,allPartiesfishingfortunasinthisoceanareobligedtoadheretothiscommissionandtoimplementitsdecisions.Itsmandateincludesthecollectionofofficialstatisticsandtheorganisationofscientificsessionsdealinginteraliawithstockassessmentandissuesrelatedtothemanagementofthetunastocks.

IOTChastakenanumberofresolutionsrelatedtoreportingofdataonbycatchinIndianOceantunafisheries.

Atthe2007meetingoftheCommissionthenameoftheWPBY22waschangedtotheWorkingPartyonEcosystemsandBycatch(WPEB)anditstermsofreferencewereexpanded.Thetermsofreferenceemphasize:

1. monitoringbycatch,improvingthestatisticaldatabaseforallfleets,andimprovinginformationoninteractionswithspeciesnotunderthemandateofIOTC;

2. researchtoevaluatetheimpactofbothabioticandbioticfactorsaffectingabundance,distributionandmigrationofIOTCspecies;

3. developmentandmonitoringofreferencepointsandindicatorsthatincorporateecosystemconsiderations;and

4. developmentofmechanismswhichcanbeusedtobetterintegrateecosystemconsiderationsintothescientificadviceprovidedbytheScientificCommitteetotheCommission.

Resolution05/05callsonCPCs23toannuallyreportcatchesofsharks,requeststheScientificCommitteetoprovidepreliminaryadviceonthestatusofkeysharkspeciesandproposearesearchplanforcomprehensiveassessmentofthesestocksofsharks,callsonCPCstoundertakeresearchtoidentifywaystomakefishinggearmoreselective,callsforfullutilizationofcapturedsharks,andprovidesanumberofguidelinesregardingsharkfinning.Italsorequiresthatthetotalweightofsharkfinsonboardnotexceed5percentoftheweightofsharksonboard,andencouragesthelivereleaseofallsharkstakenincidentallytoothertargetedspecies.

IOTChasalsoapprovedthreeresolutionsdealingwiththeconservationofseabirds.Oneresolution,approvedin2005,callsonCPCstoimplementnationalplansofactionforreducingincidentalcatchesofseabirdsinlonglinefisherieswhicharecomplementarytotheIPOA-Seabirds.TheresolutionalsoencouragesCPCstocollectinformationoninteractionswithseabirds,includingestimatesofmortalitycausedbyvesselsfishingundertheirflag.Thesecondresolution,approvedin2006,notesthattheultimateaimoftheIOTCandtheCPCsistoachieveazerobycatchofseabirdsinlonglinefisheries,especiallythreatenedalbatrossandpetrelspecies.Inanadditionalresolutionapprovedin2006,theCommissionsetanumberofguidelinesfordesignanddeploymentoftorilines.Themostrecentresolutionapprovedin2008forseabirdsspecificallyrequireslonglinevesselsfishingsouthof30°Stouseanytwoofthefollowingmeasurestoreduceseabirdbycatch:

20. TheSouthernbluefintunaaremanagedbytheCommissionfortheConservationofSouthernBluefinTuna(CCSBT).21. The1995UnitedNationsconferenceonstraddlingfishstocksandhighlymigratoryfishstocks:agreementfortheimplemen-

tationoftheprovisionsoftheUnitedNationsConventionoftheLawoftheSeaof10December1982,relatingtotheconser-vationandmanagementofstraddlingfishstocksandhighlymigratoryfishstocks.

22. WorkingPartyonBycatch23. IOTCContractingParties(orCooperatingNon-ContractingParties)

4. IOTC RESOLUTIONS THE REGULATORY FRAMEWORK


nightsetting,bird-scaringdevicessuchastorilines,weightedbranchlines,blue-dyedbait,line-shootingdevices,andoffalcontrol.Longlinevesselsfishingnorthofthatlinearerequiredtouseonlyoneofthemethods.

Finally,Resolution10/01establishingtime-and-areaclosuresforlonglineandpurseseinefisheriesintheSomaliBasinisaimedatreducingthecatchandthemortalityofjuvenileyellowfinandbigeyetunas.

Stock status of target and bycatch species

The “target species”

The“target”speciesforthelongline,pole-and-lineandpurseseinefisheriesincludeAlbacore,Bigeye,YellowfinandSkipjacktunas,aswellasSwordfish.Themostrecentstock-assessmentsconductedbyIOTCconcludedthat:• Albacore(exploitedbythelonglinefishery):It

isconsideredlikelythatrecentcatcheshavebeenaboveMSY,recentfishingmortalityexceedsFMSY(F2010/FMSY>1).ThereisamoderateriskthattotalbiomassisbelowBMSY(B2010/BMSY≈1);

• Bigeye(exploitedbyallfisheriesbutonlybylonglinesastargetspecies):BothassessmentssuggestthatthestockisaboveabiomasslevelthatwouldproduceMSYinthelongtermandthatcurrentfishingmortalityisbelowtheMSY-basedreferencelevel(i.e.SBcurrent/SBMSY>1andFcurrent/FMSY<1);

• Yellowfin(exploitedbyallfisheries):Thestockassessmentmodelusedin2011suggeststhatthestockiscurrentlynotoverfished(B2009>BMSY)andoverfishingisnotoccurring(F2009<FMSY);

• Skipjack(exploitedbypole-and-lineandpurseseine):Theweightedresultssuggestthatthestockisnotoverfished(B>BMSY)andthatoverfishingisnotoccurring(C<MSY,usedasaproxyforF<FMSY);

• Swordfish(exploitedbythelonglinefishery):Allmodelssuggestthatthestockisabove,butclosetoabiomasslevelthatwouldproduceMSYandcurrentcatchesarebelowtheMSYlevel.

Previousassessmentshadindicatedthatyellowfinstockswereheavilyexploited,but,possiblyasanindirectresultofthepiracyinthewesternIndian

Oceanwhichhaveaffectedbothpurseseineandlonglinetargeting,thestockhasrecovered.

Thealbacorestockiscurrentlytheonlysubjectofconcern,inparticularasthelonglinefleetsthattraditionallytargetedtropicaltunashavemovedtotemperatewaters,targetingalbacore.Whileyellowfinandbigeyetunacatcheshavedroppedinrecentyears,albacorecatcheshavecontinuedtorise.Piracy(seeFigure4)hasthuschangedthetargetingofthelonglinefleets,puttingadditionalpressureonthemostheavilyexploitedstock.

Neritic tunas and billfish

Theestimatedbycatchofneritictunasbyoceanicpurseseinesisof5,200t(Table5).Thisisasmallproportionofthe129,000tofkawakawacaughtin2010frommainlycoastalfisheries(IOTC-NC),60%ofwhichwasfromringnetgearintheeasternIndianOcean,withmostofthebalancefromthenorthernIndianOcean.Thesameistrueoffrigateandbullettunas,whichhadlandingsof38,000tin2009(FAO-FishStatJ).Overthelastfiveyears,theMaldivescatchofkawakawahasaveragednearly4,000t,whilethatoffrigatetunaaveraged2,500t.

TotalIndianOceanbillfishcatchesin2010werereportedat44,000t,50%ofwhichweresailfish.Hereagain,thepurseseinebycatchof149tisnegligibleincomparison.

Itisunlikely,therefore,thatthesurfacefisherybycatchcouldinfluencethestockstatusofneritictunasorbillfish.

Other finfish

Ofthe50ormorespeciesofotherfinfishinthepurseseinebycatch,theonlysignificantquantitiesareofrainbowrunner(1,200t),oceanictriggerfish(776t)anddolphinfish(356t).Allthesespeciesarepan-oceanic,short-livedandhavehighreproductivecapacity,suchthattherelativelysmallamountscaughtbyseinerscannotimpactonthestocks.

Shark status

PriortotheadoptionbyIOTCofresolution05/05,therewasnorequirementforsharkstoberecordedatthespecieslevelinlogbooks.Asaconsequence,itisonlysince2008thatsomeverypatchystatisticsarebecomingavailableonshark

IOTCResolutions–TheRegulatoryFramework


catch,mostlyrepresentingretainedcatchandnotaccountingfordiscards.

Blue sharks

Theblueshark(P.glauca)whichisnowatargetspeciesforsomelonglinefleets,notablySpain,PortugalandJapanwhichhavethemostcompletedata.Availablerecordsforlonglinecatchestotalabout5,500tfor2010.IfSpanishnominalCPUEisappliedfortheEuropeanfleetsandJapaneseCPUEforAsianfleets,theactualcatchesarecouldbeashighas13,775t,or725,000fish,suggestingadiscardof8,400t.Thepracticeofsharkfinningisconsideredtoberegularlyoccurringandontheincreaseforthisspecies(Clarke2008;Clarkeet al.2006)andthebycatch/releaseinjuryrateisunknownbutprobablyhigh.Preliminaryestimationsofmortalityathaulbackshowedthat24.7%ofthebluesharkspecimenscapturedinlonglinefisheriestargetingswordfisharedeadattimeofhaulback.Specimensizeseemstobeasignificantfactor,withlargerspecimenshavingahighersurvivalathaulback(Coelhoet al.2011a).

ThereisnoquantitativestockassessmentforbluesharkintheIndianOcean,thereforethestockstatusishighlyuncertain.BluesharksarecommonlytakenbyarangeoffisheriesintheIndianOceanandinsomeareastheyarefishedintheirnurserygrounds.Becauseoftheirlifehistorycharacteristics–theyarerelativelylonglived(16–20years),maturerelativelylate(at4–6years),andhaverelativityfewoffspring(25–50pupseveryyear),thebluesharkisvulnerabletooverfishing.However,standardisedCPUEsfromJapanese(Hiraokaet.al.2012)andfromPortuguese(Coelhoet al.2012)longlinersactuallyshowanincreasingtrend,indicativeofstablestockstatus.BluesharkassessmentsintheAtlanticandPacificoceansseemtoindicatethatbluesharkstockscansustainrelativelyhighfishingpressure.

Shortfin Mako sharks

Again,areconstructionofpossiblecatchesbasedonnominalCPUEofthedifferentfleetswouldgivecatchesofover1,585tfortheshortfinmakosharks(Isurusoxyrinchus),comparedtoreportedcatchesof525t.DataarenotavailableattheIOTCSecretariatforstockassessment,buthistoricalresearchdatashowsoveralldeclineinCPUEandmeanweightofmakosharks(Romanov

et al.2008).However,standardisedCPUEsfromJapanese(Hiraokaet.al.2012)andfromPortuguese(Coelhoet al.2012)longlinersactuallyshowanincreasingtrendfollowingearlydeclines,indicativeofstablestockstatus.CPUEintheSouthAfricanfisheriesisfluctuatingwithoutanytrend(Holmeset al.2009).

Oceanic Whitetip shark

Thereisnoquantitativestockassessmentandlimitedbasicfisheryindicatorscurrentlyavailableforoceanicwhitetipsharks(Carcharinuslongimanus)intheIndianOceanthereforethestockstatusishighlyuncertain.OceanicwhitetipsharksarecommonlytakenbyarangeoffisheriesintheIndianOcean.Becauseoftheirlifehistorycharacteristics–theyarerelativelylonglived,matureat4–5years,andhaverelativityfewoffspring(<20pupseverytwoyears),theoceanicwhitetipsharkisvulnerabletooverfishing.Despitethelackofdata,itisapparentfromtheinformationthatisavailablethatoceanicwhitetipsharkabundancehasdeclinedsignificantlyoverrecentdecades. Thepracticeofsharkfinningisconsideredtoberegularlyoccurringforthisspecies(Clarke2008;Clarke et al.2006)andthebycatch/releaseinjuryrateisunknownbutprobablyhigh.At-haulbackmortalityofoceanicwhitetipsharksintheAtlanticoceanlonglinefisherytargetingswordfishwasestimatedtobeat30.6%(Coelhoetal.,2011).Reportedcatchesin2010wereof450t,butitislikelythatcatcheswereconsiderablyhigher.

Silky sharks

Thereisnoquantitativestockassessmentorbasicfisheryindicatorscurrentlyavailableforsilkysharks(Carcharinusfalciformis)intheIndianOcean,thereforethestockstatusishighlyuncertain.SilkysharksarecommonlytakenbyarangeoffisheriesintheIndianOcean.Becauseoftheirlifehistorycharacteristics–theyarerelativelylonglived(over20years),matureat6–12years,andhaverelativityfewoffspring(<20pupseverytwoyears),thesilkysharkisvulnerabletooverfishing.Despitethelackofdata,itisclearfromtheinformationthatisavailablethatsilkysharkabundancehasdeclinedsignificantlyoverrecent


decades.However,standardisedCPUEanalysesfromJapaneselongliners(Hiraokaet.al.2012)showafairlystabletrend,whilefromSpanishdatathetrendisrisingafterhavingfallensteadilybetween1998and2007(Ramos-Cartelle,et.al.,2012).Thepracticeofsharkfinningisconsideredtoberegularlyoccurringandontheincreaseforthisspecies(Clarke2008;Clarkeet al.2006)andthebycatch/releaseinjuryrateisunknownbutprobablyhigh.

Reportedlandingsin2010wereof1,153t,comparedtothe5-yearaverage(2006-2010)of670t.

Other sharks and rays

Finally,thethreshersharks(A. vulpinusandA. superciliosus)arealldiscarded,asareallthesharksandrayscaughtinsmallnumbers(Appendix1).

IUCNclassificationTheclassificationestablishedbytheIUCNSharkSpecialistGroup(Camhiet al.2009)onthestatusofsharkscaughtbyvariousIndianOceanfisheriesisgiveninAppendixI.

Virtuallyallthesharksandrayslistedareclassifiedasbeing“Nearendangered”to“Vulnerable”.Theblue,makoandporbeaglesharksarecaughtmainlybylonglinefisheries,butsilkyandoceanicwhitetipsharksarecaught,mainlyatsmallsizes,inFOpurseseineandindriftgillnetfisheries.


5

BycatchandDiscardsinTunaFisheries


Pole-and-line, including their associated bait fishery

Pole-and-linefishingwithlivebaithasbeenpracticedinMaldivesforover1000years(Gibb,1929).Thisisstillthemainpole-and-linefisheryintheIndianOcean,togetherwithsmallfisheriesintheLakshadweepislandstothenorthandinSouthAfrica,targetingalbacore.Pole-and-linelandingsreachedahighof167,000tfortheIndianOceanin2006buthavesincefallento72,657t(2010),ofwhich56,496tweretheprimarytargetskipjack,11,036tofyellowfinandbigeyeand5,126tofnon-targettunaspecies(frigateandbullettunas)whichwereretainedandthuspresumablyconsumed.Thecatchofothernon-targetspecies(mostlydolphinfishandrainbowrunners)isnegligibleandisnotreported(M.ShihamAdam,pers. com.).Thesefisharelandedandconsumed.

TheMaldivesfisherydependedoriginallyforbaitonvarioussmallcoral-dwellingbaitfish(cardinalfish,damselfish...),whereasnowthemajorbaitspeciesaresilversprat,bluespratandIndiananchovy24whichareallfastgrowing,fastreproducingfisheswithhighratesofnatural

mortality(Lewis,1990;Dalzell,1993).Anderson(2009)usedtherelationshipbetweenthepotentialyieldfromsmallpelagicfisheriesintropicalcoastalwatersandprimaryproductivitytoestimateMSYforbaitfishtobe13,000t(±2,000t).Usingthetunatobaitratioof8.6to1,the2010catchof72,657twouldrequire8,448tofbaitfish.Ithasalsobeenestimatedthatupto30%ofthebaitfishcaughtcanbeunspecifiedlagoonfish(Andersonetal.1995),whichcouldbeasubjectofconcern,althoughitisnowreportedthat95%ofthebaitusedisfromthelightfishery(Adampers.com.)wherecaptureofjuvenilelagoonspecieswouldbeminimal(Anderson2009).

Thebaitfisharetheonlysignificantbycatch(speciescaughtintheprocessofthefishery)ofthepole-and-linefishery,amountingtosome11.6%ofthecatchoftargettunas.

Thebaitfisharetheonlysignificantbycatch(speciescaughtintheprocessofthefishery)ofthepole-and-linefishery,amountingtosome11.6%ofthecatchoftargettunas.

Longline

Asian tropical and temperate tuna longline

Figure 1: Number of hooks set (millions) from longline vessels by five degree square grid

and main fleets, for the years 2009 (left) and 2010 (right) (Data as of August 2011) (Source IOTC 2011)

24. MRC(2011)indicatesthatthelivebaitfisheryisamulti-speciesone.Over40differentspecieshavebeenrecorded,butlessthanadozendominatethecatch.ThesinglemostimportantbaitspeciesintheMaldivesisthesilversprat(Spratelloidesgracilis).

5. BYCATCH AND DISCARDS IN TUNA FISHERIES

Figure4:Numberofhooksset(millions)fromlonglinevesselsbyfivedegreesquaregridandmainfleets,fortheyears2009(left)and2010(right)DataasofAugust2011)(SouceIOTC2011)


LonglinefishingwasinitiatedbytheJapanesefleetin1952andrapidlyspreadoverthewholeoftheIndianOcean(Figure4).Korean,Taiwanese25andChinesefreezerfleetsfollowed,joinedlaterbyover1,000smallIndonesianfreshfishlonglinerswhichfishwithfewerhooksbutotherwiseinasimilarmannertothedeep-feezerlongliners.

Figure4showstheprogressivemovementofthefleetsawayfromtheEastAfricancoastwhichwaspreviouslyoneofthemostheavilyexploitedareasduetopiracy.MuchoftheeffortwasredistributedtowardstheeasternbasinoftheIndianOceanandnotablytotemperatewaters.

Thisfisherycanbedividedintofoursectors:

1. Thefisheryfortropicaltunaswhichtargetsmainlyyellowfinandbigeyetunaforthesashimimarket;

2. Thesouthernbluefinfisheryforsashimi,managedbytheCCSBTandexploitingsouthernlatitudesandwhichisnotstudiedhere;

3. Thealbacorefishery,virtuallyallTaiwanese:mostofthefishistranshippedinMauritiusandisdestinedtotheUScannedfishmarket;and

4. Theswordfishfishery.

Thelargefreezervesselsinvolvedareallofthesametypeandcaneasilytransferfromonefisherytotheother,asgearandbaitmodificationscanbeeffected“onthefly”.Sashimi-gradefishisfrozenandstoredatultra-lowtemperatures,whereascanneryfishisgenerallyplacedinholdsatabove-35°C.

Bycatch data reported by longline fleet

Reportingofbycatchisextremelyinconsistentdependingonthefleetsconcerned,withonlyretainedcatchreportedinmostcases.AnattemptismadeheretoestimatethemissingdatausingthenominalCPUE26providedbyobserversorfromthosefleetswhichwerethoughttohavereportedaccurately.Thiswasonlydoneforthetwomostcommonsharksinthelonglinecatches.

Becauseofdifferencesintargetingofthevariousfleets,theestimatesweremadeconsideringthefleetstargetingtunasandthosefishingforswordfish,asthelatterisnormallyanightfisheryusingshallowlonglineswhichhavesharkcatchratestwiceashighasthedeepdaysetsusedfortropicaltunas.Itshouldbenoted,however,thatthefiguresarrivedatcanonlybeconsideredasafirstapproximation,asthefleetsdonotnecessarilyoperateatthesamelatitudes.Blue,makoandporbeaglesharksaremuchmoreabundantintemperatewaterswheresouthernbluefinandalbacoretunafisheriesoperate,whilesilkyandoceanicwhite-tipsharksaremorecommontintropicalwaters.

Japan

In2010,84JapaneselonglinerswerefishingintheIndianOcean,withatotaleffortof37.6millionhooksforatotalcatchof17,579t,including1,008tofretainedsharks.InAugust2008,theJapanese

Table1:SharkcatchesbyyearintheJapanesedistantwaterlongliners (SourceAnon2011b)

year Blue shark Porbeagle Mako sharktonnes number tonnes number tonnes number

2006 228 13,633 16 896 162 4,0832007 452 25,993 8 607 122 3,1902008 1,280 67,992 35 2,515 156 4,3992009 1,518 73,053 17 1,087 116 3,0962010 905 49,734 9 866 137 3,220

25. ATaiwanesedriftgillnetfisheryexploitedalbacorestocksforseveralyearsuntilthisgearwasbannedbydecisionoftheUNGA.

26. CatchperUnitofEffort



Table2:Summaryofbycatchinformationcollectedby6observers(vessels)aftertheIOTCROPstarted(July,2010-January,2011)(SourceAnon2011b)

SHARKSUnidentified sharks

number RAYS number

Unidentifiedsharks 3 Stingray 549Velvetdogfish 126 UnidentifiedStingray 1Unidentifiedthreshershark 12 SEABIRDSUnidentifiedmackerelshark 4 Unidentifiedalbatrosses 1Shortfinmakoshark 32 Wanderingalbatross 1Longfinmakoshark 4 Black-browedalbatross 2Porbeagle 54 White-cappedalbatross 1Silkyshark 3 Yellownosedalbatross 2Oceanicwhitetipshark 10 Unidentifiedpetrels 1Tigershark 2 Flesh-footedshearwater 2Blue shark 961 Unidentifiedgannets&boobys 1Scallopedhammerheadshark 1 SEA TURTLESSmoothhammerheadshark 1 Loggerhead turtles 1Bigeyethreshershark 162 Oliveridleyturtle 12

Leatherbackturtle 1

governmentrequiredJapanesedistantwaterlonglinerstolandallthepartsofsharks(althoughheading,guttingandskinningareallowed).ThequantitiesgiveninTable1representsthewholeweightincludingtheweightoffins(Anon,2011b)forthethreemostcommonsharkspeciesinthelonglinefishery.Thereportedsharklandingsin2010fromthistablewereactuallyslightlyhigherthanthosereportedtoIOTCandpresumablydonotincludereleasesalive.Priorto2008,itwouldseemthatonlymakosharksweresystematicallyretainedandreportedinlogbooks.Table2liststheincidenceofbycatchspeciesintheJapaneselonglinecatchescollectedbyobservers.Numbersreleasedalivewerenotrecorded.

Korea

ThenumberofKoreanlonglinersintheIndianOceanhasdroppedinrecentyearsandwasreportedas13in2009.Thetotalcatchwasreportedas2,724tin2010,including11tofsharksand628tunspecifiedfishes(NTAD),similarto2009levels,albeitwithanincreaseintheeffortfrom3.8to5.1millionhooks.Itwouldseemthatonlythesharksretainedonboardwerereportedas,assumingthesamecatchratesasfortheJapanesefleet,sharkcatchesoftheorderof144t

wouldhavebeenexpected,bringingthediscardleveltosome770t.

Taiwan

TaiwanhasthelargestlonglinefleetintheIndianOcean,with196vesselswhichset163.5millionhooksin2010.Thetotalreportedcatchwas61,996t,including2,965tofsharksand2,404tNTAD.Again,usingJapaneseCPUE,thecatchofthetwomainspeciesofsharksshouldhavebeenoftheorderof4,530t,indicatingahighlevelofdiscards.Thiscouldwellbeanunderestimate,as,outsidethesouthernbluefinseason,theJapanesefleetfishesinmoreequatorialwatersthantheTaiwanesefleet,whichtendstotargetalbacoreandswordfishinmoretemperatewaterswherecatchesofblue,makoandwhalersharksaregenerallyhigher.

China

TheChinesefleetset15millionhooksintheIndianOceanin2010,foratotalreportedcatchof4,760t,including405tofsharksand215tofNTAD.Thesefiguresareindicativeofahighlevelofdiscardsas,usingtheJapaneseCPUEascomparator,417tofblueandshortfinmakosharkswouldhavebeenexpected.


Indonesia

TheIndonesianlonglinefleetintheIndianOceanwasreportedas1,188vessels.Whilemanyoftheseboatsarestillsmallfresh-fishFRPlongliners,therecenttendencyhasbeenforthisclassofboatstosetnearlyasmanyhooksasthelargerdeep-freezingvessels.ThetunacatchesreportedtotheIOTCScientificCommitteein2011was45,167t.TheIOTCNominalCatchdatabasegives3,074tofbillfishinaddition,togetherwith1,447tofsharksand1,184tofNTAD.ApplyingtheJapaneseCPUEtothetotalcatchesagaingivespossiblecombinedblueandmakosharkcatchesof3,900t.

Spanish and Portuguese swordfish longline

DatafromaSpanishexperimentallonglinecruise(Lezamaetal.2011)providedvaluableinformationondiscardsandbycatchtotheWPBY.Duringthatcampaign531,916hooksrepresenting539longlinesetsweremade,andatotalof28,106individualanimalsweighing1,162twerecaught.Ofthistotal,86twerereturnedtotheseaasdiscards,15twerediscardedduetopredation,40twerediscardedforotherreasonsand30twerediscardedbycatch,including25turtles,3birdsand3marinemammals,aswellasavarietyofsharks,rays,andotherfinfish,mostofthelatterlancetfishandmolas.Themammalsandturtleswerereleasedbacktotheseaalive.

Table3:SpanishandPortugueselonglinebycatchin2010(Anon.2011c)

2010 Spain PortugalHooks 3,174,705 780,000Total catch 7,364 2,091Istiophoridaenei 20Tunasnei 126Othersnei 88.5Carcharinusfalciformis 60.4 33.6Carcharinuslongimanus 79.0 2.2Carcharhinusbrachyurus 143.1Carcharhinusgalapagensis 0.2Carcharhinuslimbatus 6.2Carcharhinusobscurus 3.8Carcharhinusplumbeus 9.4CARCHARHINIDAE(nei) 10.2Exanthusgriseus 0.1Isurus paucus 0.3Isurusoxyrinchus 350.0 120.7Prionaceglauca 2,422.1 661

DatafromaSpanishexperimentallonglinecruise(Lezamaet al.2011)providedvaluableinformationondiscardsandbycatchtotheWPBY.Duringthatcampaign531,916hooksrepresenting539longlinesetsweremade,andatotalof28,106individualanimalsweighing1,162twerecaught.Ofthistotal,86twerereturnedtotheseaasdiscards,15twerediscardedduetopredation,40twerediscardedforotherreasonsand30twerediscardedbycatch,including25turtles,3birds

and3marinemammals,aswellasavarietyofsharks,rays,andotherfinfish,mostofthelatterlancetfishandmolas.Themammalsandturtleswerereleasedbacktotheseaalive.

Boththesefleetsusewireleadersandnowconsiderbluesharkasatargetspecies,suchthatthereportedcatchesareassumedtobeatruereflectionofcatches,atleastforthatspecies.



French swordfish longline

TheFrenchswordfishlonglinefleetiscomposedofsmallvesselsoperatingfromLaRéunion27. Thesevesselsdifferfromalltheotherlonglinefleetsinthatmonofilamentnylonleadersareusedinsteadofwire.Theirbycatchisthereforeinfluencedbythedifferenceincatchabilityofthisgear,aswellasthepossibilityforcertainspeciestobitethroughtheleader.Thisoffersacomparisonofwhatcouldbethecatchesoftheotherswordfishfleetsiftheuseofnylonleadersweretobegeneralised.Inaddition,manyofthespecieswhichhavenocommercialoutletsinthedistantwaterfleetsarereadilysoldontheRéunionmarketandareretained.Thesmallsizeofthevesselsmayhowevermaketheretentionofsharksdifficultbecauseofdamagefromcontactandcontaminationofthefinfishcatch.

FromApriltoDecember2007andfromJuly2008,observersfromIRDtookpartinpelagiclonglinercruises,covering63,525hooks.ThedatacollectedwasenteredintheSEALORdatabase(Bachetal.2008).Adetailedlistofallthespeciescaught,retainedcatchanddiscardswaskept.Theobserverscounted28bycatchspecieswhichwerediscarded,and8whichwereretained.Sharksrepresented46%ofdiscards,mostlyalive,withthebluesharkamountingto6.7%oftotalcatches.Thisisahighlyrelevantobservation,asthecorrespondingfigureintheSpanishandPortuguesecatchesis33and34.5%respectively.Inotherwords,nearly80%ofthebluesharkswereabletoreleasethemselvesbybitingthroughthenylonleaders.Itwouldappearthatboth“J”andcirclehooksareusedinthisfleet,andthereforethehookeffectcannotbeascertained.

South African longline

AstudyontheSouthAfricandomesticlonglinefisherywhichalsohadsomeinformationonforeignlonglinersfishingfromSouthAfricanportswasreviewedbytheWPBY.Thereportdealtwithonlyturtles,birdsandsharks.Atotalof4.1millionhooksweresetduring2000-2003bydomesticlongliners,and9%ofthesewereexaminedforcatchesofbirds,turtlesandsharks.Inadditiontothedomesticfishery,about350,000hookssetbyforeign-flagvesselsfishinginthestudyzonewereincludedinthedatabase.Itwasestimatedthat0.82birdsperthousandhookswerekilledbytheforeignfleetand0.2birdsperthousandhooks

bytheSouthAfricanfleet.Forturtlesthecatchrateforthedomesticfleetwas0.05animalsperthousandhooks,and85%ofallturtlescapturedwerereleasedalive.Thecatchofsharksforthedomesticfleetwas7perthousandhooks.AnupdateoftheSouthAfricanreportwaspresentedtotheWPBYatitsmostrecentmeeting.Theinformationpresentedcorroboratedtheearlierdata.

SouthAfricalicensed35domesticlonglinersin2005(for10years)targetingeitherswordfishortunas.Theseboatsset775,825hooksin2009,forareportedcatchof1,967t(Clarkeetal.2009)and518tofsharks(IOTC–NominalCatchdatabase).Thereportedspeciesbreakdownwas34.7tofmakoand76tofbluesharks,suggestingthatthesewereretainedandnottotalcatches.

Blueandmakosharksaccountforthemostcommonsharkspeciescaughtinthelonglinefishery.Intotal,theweightofbluesharksandmakosharksaccountedfor16%ofthatofthetunacaughtbylonglinevesselstargetingtuna.Similarly,thesesharksaccountedfor32%bythecombinedweightoftunaandswordfishcaughtinthelonglinefisherytargetingswordfish,aratecoherentwiththeSpanishCPUE.

Aconsiderableamountofsharksarereleasedduetothecurrentsharkbycatchlimitwhichrestrictstunavesselstoabycatchof10%oftunalanded.Intheswordfishlonglinefishery,thisbycatchlimitis10%ofthecombinedweightoftunaandswordfish.SouthAfricawasexploringtheimplementationofan“UpperPrecautionaryCatchLimit”forpelagicsharksfor2008(Clarkeet al.2009).

Averageseabirdmortalityhasbeenestimatedat2,460birdsperannum,from1998-2005.Thethreemostcommonspeciescaughtinthelonglinefisheryisthewhite-chinnedpetrel,thewhite-cappedalbatrossandtheblack-browedalbatross.Theaveragecatchratefortunaandswordfish-directedlonglinerscombinedwasestimatedat0.44birdsper1000hooks.Althoughcatchratesinthetuna-directedfleetissignificantlyhigherthanintheswordfish-directedfleet,bothfleetsarecatchingbirdsataratemuchhighertheFAOInternationalPlanofActionof0.05birdsper1000hooks.In2008,SouthAfricaimposedabirdlimit(of25birds)pervesselperyearinitslargepelagicfisheryasameansofreducingseabirdmortality(456birdswerecaughtfortheentirefleetasat24thNovember2009).


TurtlecatchratesintheIndianOceanhasaveraged0.05turtlesper1000hooksfortheyears2000-2003.Themostcommonlycaughtin2008wastheloggerhead(36%)followedbytheleatherback(31%).Greenandoliveridleyturtleswerealsorecordedbutinsmallnumbers.Asmallnumberofturtles(13%)wereunidentifiedbytheobserver.

Othercatchessuchasbillfishhaveremainedlowaslonglineskippersarerequiredthroughpermitconditionstoreleaselivebillfish.Oilfishandescolarprobablyconstitutedover70%ofthe“other”bycatch,withdoradoaccountingfor10%.Therearealargenumberofrayandsharkspecies(includingcrocodilesharks)thatarealsocaughtbutnotreportedastheyarediscardedatsea.

Estimated total Blue shark and Shortfin Mako catches

ThecatchesestimatedabovefromCPUEoftheJapaneseandSpanishlonglinefleetsgivetotalsforblueandshortfinmakowhichareroughlythreetimesthereportedlandings,atrespectively13,775and1,583t,comparedto5,340and525t.Someoftheunreportedcatchesofsharksmayhavebeenreleasedalive.

Depredation in longline fisheries

Depredationoffishcaughtonlonglinesmaybeamajorprobleminthattheselossesarevirtuallyneverreported.Japanisoperatingaresearchprogrammeonthesubjectandreportedfrom832longlineoperationsthat32%ofdepredationwascausedbyfalsekillerandkillerwhalesand62%bysharks.DepredationseemshigherinlonglinesetsmadeinproximitytoislandsasSeychellesandMauritiusreportedratesof19-20%,whereasLaRéunion,wherethefisheryoperatesoffshore,reported6%ofsetswereaffected(IOTC,2001).Noeffectivemitigationmeasureshaveyetbeensuccessful(Hameretal.2011).

ThetunapurseseinefisherydevelopedintheIndianOceanduringthe1980sandproduces300,000toftunaannually,mostlyforcanning.ThemainfleetisEuropeanownedandoperated,Logbookdatafromthisfisheryconsistsin

Bait use

Asinthepole-and-linefishery,thebaitusedbylonglinersshouldbeconsidereda“discard”,althoughthebait–saurypikefortropicalfisheriestargetingtunaandsquidforthosetargetingswordfish–iscaughtincompletelydifferentfisheries.NorecordswerefoundonbaituseinIndianOceanlonglinefisheries,butontheassumptionofanaveragebaitweightof100gperhook,some45,000tofbaitwouldbeneededannually,i.e.halfasmuchasthetotalrecordedcatchoflonglinersinthisocean.

The european purse seine fishery

ThetunapurseseinefisherydevelopedintheIndianOceanduringthe1980sandproduces300,000toftunaannually,mostlyforcanning.ThemainfleetisEuropeanownedandoperated,althoughsomeseinersareflaggedinSeychelles.SmallfleetswereflaggedinJapan,whichhaveceasedtooperateintheIndianOcean,andinIran,fishingmainlyintheArabianSea.

Purseseinefishingtakesplaceeitheronfree-swimming(FS)schoolsoronFADsandfloatingobjects(FO)suchastreeswashedintothesea,andoccasionallyonschoolsassociatedwithsea-mounts.TheFOfisheryhasbeencategorisedashavingrelativelyhighlevelsofbycatchcomparedtootherpurseseinemethods.

TheEuropeanpurseseinefleetiscomposedofamajorityofSpanishvessels(includingSpanish-ownedseinersunderSeychellesflag)andsomeFrenchseiners.TheSpanishseiners,whichhavesupportfrom“supply”vessels,fishalmostexclusivelyondriftingFADsandotherFOs,whereastheFrenchfleetsetonfreeschools(FS)duringtheshortseasonwhenawell-establishedthermoclinekeepsthefishinsurfacewaters.

Logbookdatafromthisfisheryconsistsinestimatedcatchesforeachset.Theestimationerroristhoughttoaverageabout10%28.Inaddition,catchesarereportedbycommercialspeciesgroups,ratherthanasindividualspecies.Becauseofthis,cachesaresampledatlandingusingastratifiedschemepermittinga

28. Usuallyunder-reportingasskippersarereluctanttoappeartoexaggeratecatches.



reconstructionofthespeciesandsizecompositionofsetswitheachstratumandset-type.Thisscheme,however,onlysamplestunas,andanybycatchretainedonboardisnotsampled(Fonteneauet al.2009).Ithasthereforeprovednecessarytore-createestimatesofpurseseinebycatchfromobserverdata.

ASpanishobserverprogramstartedin2003andtheFrenchonein2005.Thedatacoveredthewholeperiodsincethebeginningofprogramsin2003until2007foratotalof1,958observedsets(1,162freeschoolsets,762log-schoolsets,and34setsmadeonseamounts).Setsarecategorizedbetweenlog-schoolsets(FAD),freeschoolsets(FSC)andseamountssets(MsM)accordingtodirectinformationgivenbyobservers.Forseamountssetsanautomaticallocationwasalsoperformedbasedona5nauticalmileradiuscirclearoundknownseamounts(Amandéetal.2008).Thesedatahavebeenraisedtototalsforthewholefishery29.

BycatchdatawerealsocollectedfromSovietpurseseinersbetween1986and1992(Romanovetal.),aswellasinthecontextoftheBIOT(ChagosArchipelago)observerprogramme(Meesetal.2008),butthelatterarenotconsideredfurtherhereastheBIOTdatawerenotpublished.Nevertheless,theSovietdataforlogsetsisvirtuallyidenticaltotheprogrammereferredtoabove,bothinrespecttospeciescompositionandtotherelativeproportionsofbycatchspeciestotunacatchesinlog/FADsets30.

BothFrenchandSpanishfleetsdiscardlargesharksalivewherepossible(Poissonetal.2011).Largesharksaresortedoutontheupperdeck,where33%mortalitywasobserved,whereassmallspecimenssentdownthehoppertothelowerdeckwhere73%mortalitywasregistered.Highermortalitieswereregisteredinlargesetsthaninsmallsets.Intotal,20silkysharks(125.3±33.8cmtotallength)weretaggedwithMiniPATs(WildlifeComputers,Redmond,WA,USA)tostudytheirsurvivalafterrelease.Sixsilkysharksandthemakosharkdiedimmediatelyafterrelease.

29. Stratifiedbyquarter,fishingareaandfishingmode(log/FADorfreeschoolsets).30. Basedon180fishingsetsobservedintheAtlanticduring2005-2007,Chassotetal(2008)tunadiscardsoftheFrenchpurse

seinefisheryoftheAtlanticOceanwerehigherthaninthepresentanalysis,withageneraldiscardtolandingratioof 41.3 t/1000 t compared to 19.2 t/1000 t in the Indian Ocean. 31. Tunaslessthan40-45cmforklengtharegenerallydiscarded,asarefrigateandbullettunas.

Thetaggingexperimentshowsthat50%ofthereleasedsharkssurvived.Thisleadstotheconclusionthatapproximately19%ofallsharkscaughtbypurseseinecouldsurvivethefishingoperation.

TheFrenchvesselsdiscardsomebycatchbecausethevesselsaresmallerandhavelesscarryingcapacity,whiletheSpanishretainmostofthebycatch.Atlandingortranshipment(mostlyinSeychelles),stevedoresroutinelysortoutmostofthebycatchwhichisconsumedlocally.SomeofthebycatchtunastranshippedontoreefersarelandedinMauritiusandaresortedoutpriortocanning,butarenotdiscarded.


Accordingtotheseestimations,totalannualaveragebycatchfortheperiodwasestimatedat9,585t,correspondingto35.5tbycatchper1,000toftunalanded.Tunarepresents54%ofthetotalbycatchamount,followedbyotherfinfish(34%),sharks(10%),billfishes(1.5%)andrays(0.7%).TheamountsestimatedbyfishingmodeandspeciesgrouparereportedinTable4below.

OverhalfthebycatcharetunasandwouldnotbecharacterisedasbycatchunderIOTCstandards.Thesecanbespecieswhicharenotcannedforexportmarketsalthoughtheyareoftencannedforlocalmarkets(Euthynnusaffinis–kawakawa,frigateandbullettunas)undersizedfish31orfishwhichhavebeencrushedorotherwisedamagedinthefishingoperations,handlingandstorage.

31. Tunaslessthan40-45cmforklengtharegenerallydiscarded,asarefrigateandbullettunas.

Table4:Estimatedannualaverage2003-2007bycatchofthepurseseinefishery(intonnes)

Average annual Bycatch TotalAverageannual

Averageannual Percentage

Fishingmode

Tuna Fishes Sharks Billfish Rays Bycatch Catch(t) bycatch

FAD &sea

mounts

4,246 3,161 961 109 40 8,517 160,454 5.31%

Free schools

1,026 167 32 41 22 1,288 109,781 1.17%

Total 5,178 3,232 965 149 65 9,588 270,235 3.55%Percent-

age Bycatch

54.00% 33.71% 10.06% 1.55% 0.68%

Finfishbycatchaveraged3,232t/year.Themainspecieswasrainbowrunner(Elegatisbipinnulatus,37%ofthetotal),followedbypelagictriggerfish(Canthidermismaculatus,Balistidae,24%),dolphinfish(Coryphaenaspp.,11%)andcarangids(Caranxsexfasciatus,Seriolarivoliana,Naucratessp.,Carangoidesspp.,7%),withthebalance(21%)beingmadeupofsome50otherspecies.FinfishspeciescompositionbetweenFOandlogschoolswasrathersimilar,althoughthereweremoredolphinfishonFOs,andthegreatestspecies

diversitywasfromFOschools.Fishesareingeneraldiscardeddeadformorethan90%ofthenumbersand80%oftheirweight.Wahoo,commondolphinfishes,barracudasandcarangidswerethemostutilisedcategories,generallyforcookingonboard.

Thenextmostimportantbycatchgroupwas“sharks”,withatotalestimatedaverageannualcatchcloseto1,000t.Sharkbycatchwasdominatedbycarcharhinids,themostimportantbeingthesilkyshark(Carcharhinusfalciformis,79%)followedbytheoceanicwhitetipshark(C.longimanus,11%).97%ofsharkswerecaughtinFOsets.SharkspeciescompositionwasquitesimilarbetweenFOandfreeschoolssets.“Billfish”bycatchwasrelativelylow,withan

averageannualcatchof150t(range140-210t).Themostimportantspeciesweremarlins(70%,mainlyM. indicaandT.audax)andsailfish(27%).Mostbillfish(72%)werecaughtonFOsets.BillfishspeciescompositionwasquitesimilarbetweenFOandlogsets.Billfishcatchesarein85%ofcaseseitherutilised(20%)ordiscardeddead(65%).In7%ofthecases,theyarediscardedalive.




“Rays”werecaughtinsmallerquantities,withanaverageannualcatchof65t(range40-70t).65%ofrayswerecaughtonFOs.ThemostimportantspeciesgroupwastheMobulidae(42%),followedbythegiantmanta(Mantabirostris,37%),otherandunidentifiedrays(20%).RayspeciescompositionisrathersimilarbetweenFOandfreeschools,butwithalargerdiversityonfreeschools.Mostindividualsobservedwerediscardedand33%werediscardedalive

Nomentionismadehereofcetaceans,ofmarineturtles or whale sharks32.Inpractice,tuna-dolphinassociationisveryrarelyseeninthewesternIndianOcean,suchthatskippersdonotsetondolphinschools.Setsareoccasionallymadeonwhalesandonwhalesharksassociatedwithtunaschools,buttheselargeanimalseitherbreaktheirwayoutofthenetsoraretowedoutalive.Thereisnoevidenceofmortalityassociatedwithwhalesets.

Marineturtlesarealsooccasionallycaughtinpurseseinesets,almostallasjuveniles;90%arereleasedalivewithanestimateof300mortalitiesinthe5yearssampled.However,caseshavebeenoccasionallyobservedwhereturtlesweresnaggedintheoldnettingusedasattractantmaterialonFADsanddrowned.Trialsareactuallybeingcarriedoutusing“ecological”FADs(withnonetting),whichshouldleadtoeliminationofthistypeofmortality.ItshouldbenotedthatanchoredFADsintheregionnormallyusestrap-bandsasattractantmaterial,andthatnosnaggingofturtlesorsharkshaseverbeenrecorded.

Anotherentanglementissueisrelatedtotheraftdesignandturtlesclimbingontheraftsandtanglinginloosewebbing.FuturerecommendationstoIOTCwillnotethisandsupportsmallerflotationdesignsthatarenotattractivetoturtlebaskingorassurethatnettingistightlyboundtoraftswithnoloosematerial.

Withanaverageannualtotalbycatchestimatedat9,588t(3.55%ofthelandedtunaPScatch),purseseiningisconfirmedasbeingoneofthelowestsourcesoffishingmortalityfortuna-associatedspecies.Tunasaccountfor54%ofthebycatch,mostofwhicharecannedforlocalmarkets,consumedfreshorconvertedtofishmealsandoils.Otherfishes,sharksandraysaccountedfor0.64%(1,732t)ofthecatchtotalwhilesharksandraysmadeuponly0.36%.Infree-schoolsmostofthebycatchconsistsoftunas,withnegligiblecatchesofotherfishes,sharks,billfishandrays.

The effect of Piracy on purse seine fisheries

Figure3showsclearlytherecentreductionofeffortinthelonglinefisheriesandredirectionawayfromthetraditionaltropicalgroundstowardstemperateregions,notablythealbacorefishery.PurseseinerscarryarmedguardsandhaveresumedfishinguptothelimitsoftheSomaliEEZ,buttheeffectofpiracyhasneverthelessbeenconsiderable.SpanishandSeychellescatcheshavedroppedby60,000trelativeto2005-2006levels,whileFrenchlandingshavedroppedby55%.

32. Seabirdsarenotcaughtbypurseseines.

Table5:Free-schoolandlog-schoolcatches(tonnesandpercentages)in2004and2010(beforeandwithpiracy)

Total SKJ YFT BET2004 FS 191,022 18,565 9.72% 168,799 88.37% 3,658 1.92%

FO 216,226 137,882 63.77% 59,595 27.56% 18,749 8.67%2010 FS 44,604 8,826 19.79% 31,951 71.63% 3,827 8.58%

FO 232,435 141,797 61.01% 72,200 31.06% 18,438 7.93%

Thedecreaseby40,000tofyellowfinfromFrenchseinersisparticularlyspectacular.Thisistheresultofboththereductioninthenumberofseiners(10vesselsfromafleetof54seinershaveleftthe

area)andbecausetheseboatshavechangedtheirpreferredmethodsoftargetingfreeschoolsoflargeyellowfintowardsFADfishingastheyareobligedtofishinpairsandhavehadtoreducetheirsearchpatterns.



Table5showsclearlythereductionintonnageofyellowfincatchesduetopiracy,whiletherewaslittlechangeforskipjackandbigeyetuna.Whatisalsoclearisthatskipjackcatchesfromfree-schoolsetsareverylow.Whilethereductionofeffortonthemostheavilyexploitedtropicaltunastocksispositiveandmaybenefitlonglinefisheries

inthelongterm,theendresultisincreasedemphasisonFOfishing,withincreasedbycatchand,inparticular,ofjuvenileyellowfinandbigeyetuna.Conversely,theproportionofskipjackinthetotalcatchincreased.CanneriesinMauritiushavecommentedontheshiftfromlargetosmallyellowfin.

33. TunasareoftenlandedinIranforcanningwhilesharksmaybelandedmainlyinPakistan.

Table6:MainnorthernIndianOceangillnetfleets,landings,catchesofsharks,turtlesanddolphins

Country # gillnet boats

Catch (t)

% sharks

Sharks (t) Turtles # Dolphins # Source (2012)

Iran 5,920 176,692 3.2 10,128 ShahifarSriLanka 3,000 60,200 10,620 13,000 5,500?34 Herath India 2,400-3,700 320,288 28.3 2,40035 2-8000 9-10,000 MRAGPakistan 500 197,792 22,571-4,66036 ~240

(1.5%dead)

~360 Moazzam

Drift gillnet fisheries

Table7belowprovidesveryroughestimatesofthefleetsize,totalcatchandthebycatchofthemostecologicallysensitiveorganisms.Datarecordingiscomplicatedbyanumberoffeaturesofthesefisheries:• SomeofthegillnettersfromIranandPakistan

areflaggedinbothcountriesandmayland(someoralloftheircatch)inoneortheother33 (Shahifar,2012);

• Fleetsarehighlyheterogeneous,withsomeboatsreportedatunder10m,rangingtoover40mLOA;

• Netlengthsaretypicallybetween5and11km,butmaymeasuremorethan20-30km,someriggedastrammelnets;

• LandingofsharksisprohibitedinIran(forreligiousreasons)andmostofthesharksmaybelandedinPakistan(usuallydried,furthercomplicatingwetweightestimations);

• Dolphinsarenotlandedineitherofthesecountries(althoughPakistanhasestimatesofmortalitiesrangingfrom25to35permonth(Moazzam,2012)–totalmortalityofentangleddolphinsisreported;

• ThefleetnumbersinIndiaarenotreportedandwererecalculatedbasedoncatchandCPUEsfromPakistanandIran(MRAG,2012);

• Thetargetspeciesinmanyofthefleetsmaybeseerfishorsharksratherthantropicaltunas–thehighpercentageofsharksintheIndiancatchisindicativeoftargeting;

• SriLankangillnetterstypicallyattachalengthoflonglinetotheendofthegillnetstargetingsharks(Herath,2012);

• Whilethelistofspeciescaughtineachfisheryisgenerallyknown,thespecies-specificcatchisunknown,butincludesbothcoastalandhigh-seaswarmwaterspecies;

• Pakistanreportsmostturtlessurvivingandreleasedbyfishermen–thereportedcatchmayrepresentasmallproportionlanded;

• TwotothreewhalesharksarecaughtannuallybyPakistaniboatsandarelandedfortheoilrenderedfromthelivers.

Ontheunderstandingthatthefisheriesdescribedaboveareartisanalinnatureandthatdiscardsmayusuallybeonlyspecieswherelandingisprohibited(sharksinIran)orwhichareprotectedbycustom(dolphinsinIranandPakistan),theoverallpictureisneverthelessofmassiveremovalsofsharks,turtlesanddolphinsincomparisonwiththeotherfisheriesreportedoninthisstudy.


PhotobyJ.C.Rey/AIRIS-COI

6

Mitigation


Thissectionlooksatthepossibilitiesforreductionofbycatchand,inparticular,discards.

Pole-and-line

Bycatchspeciesfromthepole-and-linefisheryareingeneralconsumedlocallyandarenotdiscarded.Baitfishthereforerepresentthemainbycatchmortalityassociatedwiththefishery.Themovefromusingcoralheadspeciescaughtbylift-netstosmallpelagicswithlightattractionintheMaldivesiscertainlypositive,astheseresourcesaremoreresilientandlessdamageresultstothecoralreefecosystem.Conversely,thespratsandsilversidesarelesshardyandcannotbekeptforseveraldays(Anderson,1996).ThebaituseinMaldives,at1kgofbaitcaughtfor8.6kgoftunas(Anderson2009)andthetuna-to-baitratiocitedbyvariousauthorsfortheMaldiveshasrangedfrom7:1to11:1(Gillett,R.(2012).

Improvementofbaitholdingtechniquesmightreducebaitfishmortality37.Improvementscanbemadethroughbetterloadingtechniques,improvedbaitfishcirculationandpumpingsystems,moreefficientchummingandfeedingandmightresultinlessbaitbeingused.

Longline

IndianOceanlonglinefisherieshavefahigherlevelsofbycatchthanpole-and-lineorpurseseinefisheries.Bycatchconsistsof87speciesorspeciesgroups,includingsharks,seabirdsandturtles,manyofwhicharelistedbyIUCNasbeingthreatenedorendangered.Measurestoreduceseabirdmortalitiesincludeuseoftorilines,settinglinesatnight,belowthewaterlineoralongthesideofthelongliner(Hall,2005),linethrowers,

dischargingoffalfromareasonthevesselthatdiscouragebirdsfromthebaitedhooks,dyingthebaitblue,weightingbranchlinesandthawingbaitsandpuncturingtheswimbladdersofbaitfishsothatbaitssinkfaster(Bergin1997;Furness1999;Beldaet al.2001;Loekkeborget al.2001;Andersonet al.2002;Loekkeborgetal.2002;Robertsonetal2003),nylonleadersandvarioushookdesigns.

Ward(2007)concludedthat:“Catchratesofseveralspecies,includingsharks,wereloweronnylonthanonwireleaders,probablybecausethoseanimalsoftenescapebybitingthroughthenylonleaders.Highbite-offratesindicatethatasmanyanimalsescapefromnylonleadersasarecaughtonnylonleaders.Thefateofescapedanimalsisnotknown,althoughlargesharksaremorelikelytosurvivethanaresmallanimals.Bycontrast,catchratesofvaluablebigeyetuna(Thunnusobesus)werehigheronnylonthanonwireleaders.Bigeyetunaareprobablyabletoseewireleadersandavoidthosehooks.”Speciesabletobite-offincludedsharks,andalsotoothedfishsuch as Aleposaurusandwahoo.Increasedcostsforthereplacementofhookslostwasmorethancompensatedbytheincreasedcatchvalue,addedtothefactthatunwantedcatchesdidnotneedtobedealtwith.

ComparisonofbluesharkcatchesbytheFance-RéunionandSpanishfleetsconfirmthis,withan80%reductioninthenumberofsharksathaul-backfortheformerfleetwhichusesmonofilamentnylonleaders.However,severalexperimentswithtwoleadertypes(wirevs.monofilament)demonstratecontroversialresults;halfofthemshowhigherbycatchlevelofsharksformonofilamentleaders(Branstetteret al.,1993,Yokotaetal.,2006).

37. BaituseinMaldivesisderivedfrombaitfishcatchandnotfromthequantityusedinfishing.Asthebaitfishhavelowsurvivalaftercapture,thisisabettermeasureofbaitfishextraction.

6. MITIGATION


Table7:Percentageoforganismsdeadathaul-back(SourceCoelhoetal.2010)

Code Species/Family n % DeadBSH Prionaceglauca 2,358 24.7SMA Isurusoxyrinchus 430 56FAL Carcharhinusfalciformis 31 74.2SPZ Sphyrnazygaena 25 84BTH Alopias superciliosus 19 68.4PLS Dasyatisviolacea 16 0JAM Mobulidae 14 0

Survivalofthesharksafterbite-offordiscardalivearecriticalelementsofecosystemmanagement(Boggs,1992;Davis,2002).Thereisofcoursenoevidencethatthesharkswhichseveredthenylonleaderssurvivedbutthejaw-hookedsharkswerepresumablylessstressedatbite-offthaniftheyhadremainedonthelineformanyhours.Campana(2009)showedthatalljaw-hookedandreleasedbluesharksurvived,whilesharksswallowedhookwillmostprobablydie.However,astudyinvolvingsixbluesharkswitholdremainsoffishinghooksintheirbodiessufferedfromfibroms,stomachinflammationorinflammationoftheesophagealareacausingobstruction(Borucinsaet.al.2002),indicatingthatthosewhichareunabletodislodgeembeddedhooksarehandicapped.

NOAAhasworkedforthelastthreeyearsintheGulfofMexico(EricSchwaab,unpublished)with“weak”circlehookswhichcanbestraightenedoutbylargefishbuthavebeenshowntogivebetteryellowfincatches.Thesemightallowsomeofthelargesharkstoescape,butbluesharkswhichaverageabout20kgintheswordfishlonglinefisheryareunlikelytobeabletostraightenthesehooks.

NOAAisalsoinvolvedinthetestingof“weak”circlehooksintheUSHawaiibasedlonglinefisheryasameanstoreleasetoothedcetaceaninteractionswhilestillretainingareasonableamountoftargetcatch.Thisinitiativewillbemandatedbytheagencyinresponsetolowbutecologicallysignificantinteractionswithwhathasbeendeterminedtobeasmallsub-populationoffalsekillerwhale(Pseudorcacrassidens).Theuseofhooksincorporatingrareearthmetalandmagneticdeterrents38(Stoneretal.2008,Brilletal.2009)confirmedbytheAustralianDepartmentofPrimaryIndustriesandFisheriesandJamesCookUniversityonavarietyofsharkspeciesmayofferevenbetterprospectsofreducinglonglinesharkcatches.

TheEuropeanUnionresearchprogramMADE(Mitigatingadverseimpactsofopenoceanfisheries)iscurrentlylookingatwaystoreducebycatchandecologicalinteractionsofpurseseineandlonglinefisheries;primarilyintheIndianandAtlanticoceans.Themainobjectivesrelativetolonglinefisheriesistotestandproposemeasurestoreducethebycatchofsharksandjuvenileswordfishtakenbypelagiclongline.

38. Sharksareverysensitivetoelectricandmagneticfields.

ThetypeofhookcouldalsohaveaninfluenceasRomanov(2010)showsthatpercentageofjaw-hookedfishoncirclehooksis1.33timeshigherthanfortunahooksand4foldhigherthanforJ-hooks.Similarlycumulativepercentageofgillandguthookedfishoncirclehookistwo-timeslowerthanfortunahookand3.8timeslowerthanforJ-hooks.

Table7,belowshowsthat,onthewireleadersusedbythePortuguesefleet,ahighproportionofmako,silky,whitetipandthreshersharksaredeadwhenthelinesarerecovered,while75%ofbluesharksandmostrayssurvived(Coelhoetal.2010).Notethat,intheSEALORobserverreport,mostofthesharksrecoveredwerereleasedalive(Bachetal.2008).Thelengthoftimeduringwhichasharkisonthelinethereforehasamarkedinfluenceonmortality.

Mitigation


Purse seine

The ISSF39iscoordinatingstudiesandresearchcruisesintheIndian,AtlanticandPacific(EPO,WCPO)OceansspecificallytotestanddevelopmitigationmeasuresforpurseseinefisheriesoperatingonFADs(http://iss-foundation.org/science/projects/bycatch-reduction/).Theprojectiscontractingcommercialpurseseinevesselsinallthetropicaloceanstotestavoidance,releaseandconditionofoceanicsharks,whaleshark,marineturtles,non-targetfinfishandundersizedandjuvenileyellowfinandbigeyetuna(Restrepo,2010).An11dayresearchcruiseintheIndianOceanthathasbeencompletedconcentratedonthebehaviourofsharksandfinfishbycatcharoundFADs.Amoreextensivesixweekbycatchmitigationcruiseisbeingconductedbytheprogramduringthesecondquarterof2012(Itanoet al.2011).A73daycruisehasbeencompletedintheEasternPacificOceanonandEcuadorianflagpurseseinerasdescribedinSchaeferandFuller(2011).A41dayISSFresearchcruiseintheWCPOcompletedinJuly2012onaUSflagvesseloperatingnorthofAmericanSamoa.ThiscruiseisdescribedbyHutchinsonet al.2012;Itanoetal.2012A;Itanoet al.2012b;andMuiret al.2012)butanalysedresultsarenotyetavailable.

Severalapproachesarebeingtestedthatexaminebycatchreductioninthreestages:beforearrivingataFAD(viaacousticdata);onarrivalandusingacousticinstruments;howtoremovebycatchfromtheencircledFADpriortoloading;releaseofbycatchduringtheloadingprocess;andsurvivalandconditionofpost-releasedanimals.AfulldescriptionoftheseplansthatarebeingdevelopedbyscientistsinconsultationwithindustryareavailableontheISSFwebsite40,

Oneavenueofmitigationofturtlesnagginghasbeentopromotetheuseof“ecological”FADsbypurseseinefleetswithtwoobjectives:1)constructionfromnon-entanglingmaterialstoavoidmarineturtleandsharkmeshingand2)constructionofFADsfrombiodegradablematerialstoreduceimpactsofnylonandotherplasticsintheenvironment.

39. InternationalSeafoodSustainibilityFoundationhttp://iss-foundation.org/40. http://iss-foundation.org/science/projects/bycatch-reduction/skippers-workshops/ http://iss-foundation.org/science/projects/bycatch-reduction/fieldwork/41. Thesesmallsetsareconsiderednon-economicanditissuggestedthatthemainreasonformakingthamistokeepcrews

“motivated”.

Asisstatedabove,mostfree-schoolsetsintheIndianOceanareonlargeyellowfinanditisprobablethatitisthereductioninthistargetingasaresultofconstraintsontheFrenchseinersbecauseofpiracywhichhasallowedthestocksofthatspeciestorecover,aswellaspotentiallyincreasingtherecruitmenttothelonglinefishery.Thetrade-offhasbeenmoreFADfishing,withacorrespondingincreaseinbycatchandinlandingsofskipjackandofjuvenileyellowfintuna.Purseseinebycatchlevelsaresolow,however,thatanincreaseinFSsetsisnotdesirable,althoughthereisapossibilitythatlargercatchesofjuvenileyellowfininFOsetsmightinthelongtermhaveanegativeimpactonthestocks.

Thisissimilartoanunforeseentrade-offthatisgainingincreasingattentionconcerningthemeasuresadoptedbytheIATTCtodealwithdolphinby-catchintheEasternPacifictunafishery(Hall1998).Datanowavailableindicatethatthe‘cost’ofthespectacularreductionindolphinmortalitiesachievedbythefleethasbeenanorderofmagnituderiseinthebycatchofundersized,non-usabletunaandalargeincreaseinthemortalityofseaturtles,sharks,andotherfishspecies(Norriset al.2002).Theseincreaseshaveariseninpartbecausefishershaveswitchedfromtargetingtheireffortsonthelargeyellowfintunathatassociatewithdolphinschoolstotargetingthesmalleryellowfinandbigeyetunathatareunabletokeepupwithdolphinschoolsandarefoundaroundinanimatefloatingobjects,suchaslogs(Norriset. al.2002).Anotherexampleoftrade-offincludesthehighseasdriftnetbanthatwasenactedin1992.Thisaction,wascertainlyeffectiveinreducingsomeformsofbycatch,butitalsoresultedintherapidexpansionofalonglinefishery,whichhasby-catchproblemsofitsown.

AnewapproachissuggestedbyDagornet.al.(2012a),whichconsistsinmakingpurseseinesetsonlyonschoolsestimatedtobeover10t41. Ratiosofbycatchtotargetcatcharehighestwhencatchesaresmall:thesmallestclassofcatchesresponsibleforthehighesttotalportionofbycatch(23%–43%)whileonlycontributingnegligiblytothetotaltargetcatch(3%–10%).Reducingthenumberoffishingsets(apartofthetotaleffort)whilemaintainingthesametotalyieldcouldcontribute


toasubstantialreductionintheimpactsofhumanactivities.

ResearchconductedundertheISSFBycatchprojectandtheEUfundedMADEprojectforthedevelopmentofmethodstoreducetheFADpurseseinefishery-inducedmortalityofsilkysharksincludednonentanglingFADs,behaviourofsilkysharks,attractionofsharksawayfromFADs,doubleFADexperiments,attractionofsharksoutsidethenet,andsurvivalofsharksreleasedalive(Dagornet.al.2012b).Thefishery-inducedmortalityofsilkysharksbypurseseinerscouldbereducedby10-20%ifcrewsadoptthebestpracticeofreleasingallsharksobservedaliveonboard.Testsofanescapepanelintheseinewerenotconclusive,however,despitethefactthatthesharksappeartoconcentrateinaparticularportionofthenet,awayfromthetuna.Similarly,attractingthesharksoutofthenetwithbaitorbytowingouttheFADswerenotsuccessful.

OneregulatorymechanismthatisbeingincreasinglyusedbytunaRFMOstomitigatebycatchisthemandatingoffullretentionoftargetandbycatchbypurseseinefleets.Theideaisthatpurseseinecaptainswilldevelopbetterwaysandskillstoavoidsettingonbycatchorundersizedmarkettunaiftheywillberequiredtoloadandlandeverythingthatentersthenet.However,fullretentionmustbeimplementedwiththeunderstandingthatlivereleaseofsomespeciesispreferabletoalegislativerequirementtolandeverything(McCoyet.al.2007).

Substitution of pole-and-line for purse seine fisheries

AnendtoFOfishingimposedthroughmarketpressuresislikelytohaveseriousconsequences,includingpossiblythecollapseofthepurseseinefisheryintheIndianOcean.Sharp(1979)wasthefirsttosuggestthatpurseseiningmightbepossibleintheIndianOceanforpartoftheyearwhenthethermoclinewassufficientlyshallowandstructuredtokeeptunasinsurfacewaters.Theseconditionsonlyexistforthreetofourmonthsofthe

year.Thissituationhasbeenconfirmedbythirtyyearsofexperience.ThepurseseinefleetcouldobviouslynotremaininactiveeightmonthsoftheyearandwouldmostlikelymovetootheroceansunlessmarketsarefoundthatacceptfishcaughtinFO sets.

The question then arises – could pole-and-line fisheries be developed to replace the 250,000-300,000 t of purse seine landings?

Pole-and-line trials in the Indian Ocean

Priortothe1980sitwasthoughtthatpurseseinefisherieswerenotpossibleintheIndianOceanandinterestfortheexploitationofskipjackconcentratedinlivebaitpole-and-linefishingwhichwereknowntoworkintheMaldives.ThefirstsuccessfulenterpriseintheIndianOceanoutsidetheMaldiveswasCOMANIP,aMalagasy-JapanesejointventurewhichoperatedelevenboatsbasedonNosyBéintheMozambiqueChannel(Marcille,unpublished).Thisfisherycollapsedforpoliticalreasons,andattemptstofindbaitresourcesfailedinMauritius,Rodrigues,St.Brandon,theNazarethandSayadeMalhaBanks(Ardill,unpublished).TwoBasqueboatsthenfishedfromSeychellesin1981-82(Cort,1982),findinglimitedquantitiesofbait(mainlyjuvenilescad)forabout9monthsoftheyear.AsubsequentSeychelles-Frenchjointventuresubsequentlyfailed.Marsac(1983)reportedthatSeychellesbaitresourceswerelimitedandsuggestedtheconstructionofbait-holdingcages.

Attemptswerethenmadetodeveloppole-and-linefisheriesinMozambiqueusingCapeVerdetechniques(Moreira-Rato,unpublished),andinZanzibar(Lee,unpublished),bothwithFAOsupport.Finally,ZanzibarfishermenweretakentoMaldivestolearnthetechniques.Noneoftheseinitiativesweresuccessful,possiblyinpartbecauseofthelackofentrepreneurialskillsandofinvestmentfunds,aswellasthedifficultiesinmasteringtechniquesofbaitandtunafishingforeastAfricanpopulationsunfamiliarwithoceanicfisheries.

Mitigation


InthecontextoftheIOCRegionalTunaTaggingProject,surveysdemonstratedthegeneralpaucityofoceanicbaitresources,otherthanoffthecoastofOman.TheRTTPtaggedover150,000fishusingschoolsassociatedwiththetaggingplatform,withoutbait.TheseoperationsobviouslydidnotattaincommercialcatchratesbutbaitwasfoundnearMafiaIsland(Tanzania),theOmancoast,theNosyBéareainMadagascarandSeychelles(indiminishingorder)(J-PHallier,pers.com.2012).

Whilethereisobviouslysomepotentialforexpansionofthepole-and-linecatchintheIndianOcean,theprocessislikelytotakealongtimeandtorequiresubstantialinvestmentandtechnicalsupport.Makinguptheshortfallincannerysupplyintheeventofacollapseofthepurseseinefisheryiscertainlycompletelyunrealistic.ThereislittlechancethatpoleandlinefishingcandevelopinthewesternIndianOceangivenlimitedbaitfishresourcesunlessahugedifferentialinlandedpriceforpoleandlinecaughttunadevelopswhichisunlikely.

Carbon footprint of tuna fisheries

Theissueoffuelconsumptionandcarbonfootprintisbecomingincreasinglyrelevant,bothinoperationalcostsandwithrespecttoGlobalwarming.Pelagicfisheries(tunaandsmallpelagicseining)areamongthemostefficientinrelationtofuelconsumption,particularlyincomparedtotrawling.Nevertheless,therearesignificantdifferencesbetweengearsandfishingmethods.

NostudieshavebeenpublishedontheIndianOcean,buttherehavebeenseveralconcerningthePacificOceantunafisheries.

Thrane(2009)estimatedthecarbonfootprintfortunafisheries.Thefigurearrivedatforpurseseinerswas1.15–5.27kgCO2/kgoflandedtuna,whilethatforlonglinerswas6.64–8.86kg CO2/kg.Theparametersusedforpole-and-linedonotseemtoequatetothosefoundintheMaldives.Gillett(2011)however,estimatesthatintheSolomonIslands588litresoffuelareusedpertonneofpole-and-linetunaand306litresoffuelpertonneofFAD-associatedpurseseinetuna,i.e.nearlyhalftheamountusedinpole-and-linefishing.Thesearchtimeforseinersin

targetingfree-schoolsismuchgreaterthanthesteamingtimeinmovingfromoneFADtothenext,particularlyasFADsarenowmostlyequippedwithGPStranspondersthatgiveanaccuratepositionfixtothefishingvessel.Theuseof“supply”tendersbytheSpanishfleetprobablymakesforanevengreaterdifference,astheseboatshaveverylowpowercomparedtotheseiners.

Inaseparatestudy,purseseinegear,wasfoundtoburn,onaverage,368litresoffuelperliveweighttonneoflandings,whilelonglineburnedonaverage1,070andpoleandline1,490litrespertonne(Tydmerset al.2011).

AsampleoflandingsandfuelburnfromtwofacilitiesintheSouthoftheMaldivesbetweenand2011gaveanaveragerangingfromlessthan100litrespertonneoftunain2006tocloseto300litresin2011witharegularlyincreasingtrend(M.ShihamAdam,pers. com.),i.e.roughlyequivalenttotheconsumptionofFAD-associatedpurseseinersandaquarteroftheburnreportedbyTydemersfortheAtlantic.SuchlowconsumptionfiguresmaybespecifictotheMaldives,however,wheremuchofthepole-and-linefishingisconductedonFAD-associatedschoolsanddaytripswithlittletimespentsearchingforfree-swimmingschools.


7

Mitigation


Stock status

TheIOTCspeciesWorkingPartieshavedeterminedthat,ofthestocksexploitedbytheexport-orientedfisheries,onlyalbacorearecurrentlybeingfishedataboveMSY,andswordfishisabove,butclosetoMSY.Yellowfinandbigeyetunawhichhadhistoricallybeenheavilyexploitedhavenowrecoveredandskipjack,thestockwhichisthemostrobusttoexploitation,hasanabundancewhichisabovethatatwhichthebiomasswouldproduceMSY.

IUCNlistsmostofthesharks,rays,marineturtlesandseabirdscaughtinassociationwithtunafisheriesasbeingnearthreatened,vulnerableorendangered,suchthatmitigationofthesemortalitiesisapriority.Blueshark,targetedbysomelonglinefleets,maybeanexceptioninthatCPUEtrendsareindicativeofstablepopulations.

Bycatch and discards

Thisstudyshowsthat,intheIndianOceantunafisheries,purseseineeffortonfreeschoolsresultsinthelowestbycatchlevels,whileproducingover80%ofhighervalueyellowfinandbigeyetuna.Floatingobjectsetsresultinnearlyfivetimestheamountofbycatch,withskipjackconstitutingnearly70%ofthetargetcatch,albeitwithnearly28%innumbersofsmallyellowfinandbigeyetuna.Thejuvenileyellowfinandbigeyeproportionmaycontributetogrowthoverfishingandsecondaryinteractionastheyrecruitorwouldhaverecruitedintowiththehighvaluelonglinesashimifishery.

InbothFSandFOsets,themainbycatchspeciesareneritictunas(54%),followedbyfinfishandcartilaginousfish.CatchesoftheneritictunasaremodestcomparedtothoseoftargetedcoastalfisheriesintheIndianOcean.Fromtheestimatedannualcatches,theannualcatchofnosinglenontargetspeciesismorethan1,200t.Where

thefinfishareconcerned,mostofthespeciesareabundant,short-lived,reproduceearlyandhavepan-oceanicdistribution.Thesharks,mainlysilkyandoceanicwhitetip,arethustheprimarysubjectofconcern.

IntheFADfishery,marineturtlesandsharksareoccasionallysnaggedbuttheindustryisdeveloping“ecological”FADswhichshouldeliminatethesemortalities.

Pole-and-linebycatch,at11.6%ofthetargetcatchesforbycatchalone,ismuchhigherthanthepurseseineFOrates.Thebaitfish,however,aretypicallyspecieslowinthefoodchainwithrapidturnover.Thetargetspecieshaveabi-modalsizedistribution,withalargeproportionatsmallsizeswhichhavealowerconversionfactorforcanning.

However,thisfisheryproducesthehighestproportionofskipjack.

Itwasnotedthatthesurfacefisheries(purseseineandpole-and-line)discardverylittlefish.

Takingthelonglinefisheryasawhole,reportedbycatchlevelsareatslightlyover6%ofthecombinedtunaandbillfishcatches.Indicationsarehoweverthatunder-reportingofsharkcatchesmaybebyasmuchasafactorofthree,whichwouldbringthebycatchleveltoaround19%oftargetcatches.ObserverdatafromtheSpanishandPortuguesefleetsplaceddiscardsat14%ofthetotalcatchor17%oftheretainedcatch.Thediscardsincluded1.3%frompredationand3.4%from“otherreasons”,whichmighthaveincludedspoilageorhigh-grading.However,intheIOTCNominalCatchdata,reportedsharkandNTADcategoriesarenearlyequaltotargetcatches,indicatingthattheproportionofthesespeciesismuchhigherintemperatewaterswherethesefleetsoperate,fishingwithswordfishlonglines.Amoredetailedanalysisshouldbeconductedusinggeartypeandareastratifications.

7. CONCLUSIONS


Thebaituseinthefisheryprobablyamountstohalfthetotalcatch,albeitofspecieswhicharelowinthefoodchainandhavehighturnover,andoftencaughtinadifferentocean.

Inthelonglinefisheries,withtheexceptionoftheSpanishfleetforwhichbluesharkareatargetspecies,sharkslistedbyIUCNarebyfarthelargestcomponentofbycatch,whichplaceslonglinesasthemostecologicallydamagingtunafishery,withtheexceptionofthedriftgillnetfisheries.

Finally,althoughnoreliablefiguresareavailable,driftgillnettersinthenorthernIndianOceanappeartohaveshark,marineturtleandcetaceancatchesordersofmagnitudehigherthanthoseoftheothermajorgears.Inaddition,noneofthefleetsareinconformitywiththeUNGAbanontheuseofdriftnetslongerthan2.5km.Thenumberofboatsandfishermeninvolved,aswellasthenutritionalneedsofthecoastalpopulations,however,islikelytomakeitvirtuallyimpossibletoregulatethesefleetsandreducebycatchofecologicallysensitivespecies.

Withsuchlargebycatchinthegillnetfisheries,bycatchinpole-and-line,purseseineandlonglinefisheriesappearinconsequential,althoughmitigationmeasuresaretobeencouraged.

Mitigation

Pole-and-line

ParticularattentionwasplacedontheNGOpressureonsourcingcanneryrawmaterialfromFAD-freefisheries,andnotablyfrompole-and-line.Whilethereisobviouslysomepotentialforexpansionofthepole-and-linecatchintheIndianOcean42,theprocessislikelytotakealongtimeandtorequiresubstantialinvestment43 andtechnicalsupport.Makinguptheshortfallincannerysupplyintheeventofacollapseofthepurseseinefisheryiscertainlycompletelyunrealistic.Limitedbaitfishresourceswasidentifiedasamajorconstraint,aswasthehigherpriceofFAD-freefish44.Italsocostsmoretocatchatonneoftunabypole-linethanbypurseseine.

Themainavenueforbycatchmitigationwasthereforeidentifiedasbeingmoreefficientuseof

baitfish.DiscardingofneritictunasandtheNTADcomponentshouldnotbeencouragedinsmall-scalefisherieswherebycatchisconsumed.

Purse seine

AshiftfromFOtoFSsetswouldresultinreducedskipjackcatchesandincreasedpressureonthemoresensitiveyellowfinandbigeyetunastocks,withprobableinteractionswithlonglinesashimifisheries.BecauseoftheshortFSseason,purseseinersmightalsoleavetheIndianOcean,withseriouseconomicandsocialconsequencesinthewesternIndianOceanislands.

ApproachesarebeingtestedbyISSFthatexaminebycatchreductioninthreestages:beforearrivingataFAD(viaacousticdata);onarrivalandusingacousticinstruments;howtoremovebycatchfromtheencircledFADpriortoloading;releaseofbycatchduringtheloadingprocess;andsurvivalandconditionofpost-releasedanimals,aswellasnonentanglingandbiodegradableFADSappeartogivethebestprospects.Discouragingsetsonsmallschoolsisalsolikelytosignificantlyreducebycatchandmightevenhavepositiveeconomicconsequences.

Longline

Inlonglinefisheries,themitigationmeasuresusedforseabirdsappeartohaveresultedinmarkeddecreaseininteractions.Severalsharkspeciesseemhowevertobeheavilyexploited,withuncertainreportingofcatches.Anumberofmitigationmeasuresmightreducethisunwantedbycatch.Chiefamongthesewouldbetheadoptionbyallfleetsofmonofilamentnylonleaders.TheresultsoftheFrance/Réunionlonglinerswouldneedtobeconfirmedandresearchinitiatedonthesurvivalofsharkswhicharecut-offwithcirclehooksembeddedintheirjaw.Thiscouldprobablybeachievedusingpop-uptagstomeasurelong-termsurvival.AstheSpanishandPortuguesefleetsretainsbluesharksasatargetspecies,aspecialderogationmaybenecessarytopermittheuseofwireleadersforfleetstargetingsharksifabanonwireleadersweretobeenacted.Finally,thedeterrenteffectofmagnettechnologyassociatedtohooksneedstobetestedurgentlyonoceaniclonglines.

Conclusions


Other ecological issues

ThelowestconsumptionoffuelpertonneofcatchisinMaldivianpole-and-lineoperationsfollowedbyFOseinerfisheriesandFSfisheries.Longlinersconsumeabouttwiceasmuchfuelpertonneofcatchasseiners(Tydmerset al.2011).

Enforcement and verification

Abanondiscardingdeadorganismsinallfleetswouldcertainlyhaveapositiveeffectinencouragingadoptionoftechniquesleadingtoescapementofbycatchorganismssuchasundersizedfishinpurseseinefisheriesandsharksinlonglinefisheries.Onthesmallerlongliners,suchameasuremightposeproblemsinstoringonboardorganisms(suchassharks)whichmightcontaminateothercomponentsofthecatch.Apositivesidetosuchregulationswouldcomefromthecontributionofthisfishtonutrition:Mauritiusalreadytakes4,500tofbycatchfromlonglinerstranshippinginPortLouiswhichissoldonthelocalmarket(SheikMamode,2011).Verificationofdiscardingbanswouldusuallyinvolveobservers.ThepurseseinefleetclaimsatpresentthatthespareaccommodationisfullytakenupbytheguardscarriedtocounterpirateattacksandlongtripsindifficultconditionsmakesobservercoverageontheAsianlonglinefleetverydifficult.Itisthereforenecessaryasamatterofprioritytodevelopremotesensingmonitoringdevicesadaptedtothedifferentfisheries.

Closing comments

Finally,itshouldbenotedthattheIUCN-CEMFisheriesExpertGroup(FEG)andtheEuropeanBureauforConservationandDevelopment(Garcia,2010)concludedthatafisheriesmanagementregimebasedonretentionofallspeciesandsizegroupsincatchesmayinpracticeleadtolessharmfulecologicaleffectsandhighersustainableproductionthanselectivetargetingofparticularspeciesandsizes.Atthespeciesassemblagelevel,thisimpliesthatmanagement

shouldaimatawidedistributionofthefishingpressuretobalancedirectandindirectimpactsacrossspecies.Fromthatperspective,by-catch,ifmaintainedwithinlimitsimposedbysustainability,maynotbeanimpedimenttomaintenanceofcommunitystructureandecosystemstability(Zhou,2008).

Zhouetal.(2010)arguethat:Globally,manyfishspeciesareoverexploited,andmanystockshavecollapsed.Thiscrisis,alongwithincreasingconcernsoverflow-oneffectsonecosystems,hascausedare-evaluationoftraditionalfisheriesmanagementpractices,andanewecosystem-basedfisheriesmanagement(EBFM)paradigmhasemerged.Aspartofthisapproach,selectivefishingiswidelyencouragedinthebeliefthatnon-selectivefishinghasmanyadverseimpacts.Inparticular,incidentalbycatchisseenaswastefulandanegativefeatureoffishing,andmethodstoreducebycatchareimplementedinmanyfisheries.[….]However,recentadvancesinfisheryscienceandecologysuggestthataselectiveapproachmayalsoresultinundesirableimpactsbothtofisheriesandmarineecosystems.A“balancedexploitation”approachmightalleviatemanyoftheecologicaleffectsoffishingbyavoidingintensiveremovalofparticularcomponentsoftheecosystem,whilestillsupportingsustainablefisheries.

Subjecttotheapplicationandverificationofthebycatchmitigationmeasuressuggestedabove,changesinthepurseseineregimesuggestedbyNGOsleadingtoareductioninFOsetsorevensubstitutionofpurseseiningbypole-and-linefisheriesappearsnotonlyunrealistic,butcouldhaveundesirableenvironmentaleffects.


REFERENCES

Alverson,D.L.,Freeberg,M.H.,Murawski,S.A.andPope,J.G.(1994)Aglobalassessmentofbycatchanddiscards.FAOFisheriesTechnicalPaperNo.339FAO,Rome,233pp

Amandé,JustinMonin,JavierAriz,EmmanuelChassot,PierreChavance,AliciaDelgadoDeMolina,DanielGaertner,MuruaHilario,RenaudPianet,JonRuiz(2008):By-catchandDiscardsoftheEuropeanpurseseinetunafisheryintheIndianOcean,:Estimationandcharacteristicsforthe2003-2007period;IOTC-2008-WPEB-12

Anderson,S.andMcArdle,B.(2002)SinkrateofbaitedhooksduringdeploymentofapelagiclonglinefromaNewZealandfishingvessel.NewZealandJournalofMarineandFreshwaterResearch36,185–195.

AndersonR.Charles(1996)TheMaldivianTunaLivebaitFishery-StatusandTrendsinWorkshoponintegratedreefresourcesmanagementintheMaldives,BOBP/REP/76

Anderson,R.C.(2009).LivebaitComponent-FinalReport.MaldivesEnvironmentalManagementProject(MEMP),TechnicalAssistancetoBaitfishMonitoring,33pages.December2009.http://www.mrc.gov.mv/index.php/publications/

Anderson,R.Charles,M.ShihamAdamandMarieR.Saleem,2011:SharklonglinefisheryinthenorthernMaldives;IOTC-2011-WPEB07-27rev_1

Anderson,R.C.andSaleemM.R.(1995)Inter-annualvariationsintheutilizationoflivebaitintheMaldives.Rasain,15:193-216.

Anon(2011):ReportoftheFirstMeetingoftheBycatchJointTechnicalWorkingGroupLaJolla,CAJuly11,2011inFourteenthSessionoftheScientificCommittee,Seychelles,12–17December2011,IOTC–2011–SC14–06[E]

Anon,(2011b):NationalReportofJAPAN(2011),NationalResearchInstituteofFarSeasFisheries(NFIFSF),FisheriesResearchAgency(FRA)andFisheriesAgency,GovernmentofJapan,IOTC-20110SC14-NR12Rev_1

Anon.(2011c):Rapportdel’UnionEuropéennepourleComitéScientifiquedelaCTOIde2011(Données2010);IOTC-2011-SC14-NR06

BachPascal,NjaratianaRabearisoa,TheoFilippi&SéverineHuba(2008),:ThefirstyearofSEALOR:DatabaseofSEA‐goingobserversurveysmonitoringthelocalpelagicLOnglinefisherybasedinLaReunion;IOTC-2008-WPEB-13

Bergin,A.(1997)Albatrossandlonglining–managingseabirdbycatch.MarinePolicy21,63–72.

Belda,E.J.andSanchez,A.(2001)SeabirdmortalityonlonglinefisheriesinthewesternMediterranean:factorsaffectingbycatchandproposedmitigatingmeasures.BiologicalConservation98,357–363.

Berkeley,SAandWLCampos(1988)RelativeabundanceandfisherypotentialofpelagicsharksalongFlorida’sEastcoast.MarineFisheriesReview,50(1):9–16.

Boggs,C.H.,(1992)Depth,capturetime,andhookedlongevityoflongline‐caughtpelagicfish:timingbitesoffishwithchips.Fish.Bull.US90,642‐658

BorucinskaJ.,KohlerN.,NatansonSkomal,G.(2002).Pathologyassociatedwithretainedfishinghooks

References


inbluesharks,Prionaceglauca(L.),withimplicationsfortheirconservation.JournalofFishDiseases25(9),pp515-521.

Branstetter,S.A.,andJ.A.Musick.(1993).Comparisonsofsharkcatchratesonlonglinesusingrope/steel(Yankee)andmonofilamentgangions.MarineFisheriesReview55,no.3:4-9.

Brill,R.,Bushnell,P.,Smith,L.,Speaks,C.,Sundaram,R.,Stroud,E.,Wang,J.(2009).Therepulsiveandfeedingdeterrenteffectsofelectropositivemetalsonjuvenilesandbarsharks(Carcharhinusplumbeus).FisheriesBulletin.FB-3298

Camhi,MD,SVValenti,SVFordham,SLFowlerandCGibson(2009)TheConservationStatusofPelagicSharksandRays:ReportoftheIUCNSharkSpecialistGroupPelagicSharkRedListWorkshopIUCNSpeciesSurvivalCommissionSharkSpecialistGroup.Newbury,UK.x+78p.

Campana,SE,WJoyceandMJManning(2009)BycatchanddiscardmortalityincommerciallycaughtbluesharksPrionaceglaucaassessedusingarchivalsatellitepop-uptags.MarineEcology-ProgressSeries,387:241–53.

ChassotE.,AmandeM.J.,ChavanceP.,PianetR.,DédoR.G.,2008.Apreliminaryattempttoestimatetunadiscardsandby-catchintheFrenchpurseseinefisheryoftheeasternAtlanticOcean.DocICCATSCRS/2008/117

ChavanceP.,AmandeJ.M.,PianetR.,ChassotE.,DamianoA.,(2011):BycatchandDiscardsoftheFrenchTunaPurseSeineFisheryduringthe2003-2010PeriodestimatedfromObserverdata;IOTC-2011-WPEB07-23

ClarkeSC,McAllisterMK,Milner-GullandEJ,KirkwoodGP,MichielsensCGJ,AgnewDJ,PikitchEK,NakanoH,andShivjiMS,(2006).Globalestimatesofsharkcatchesusingtraderecordsfromcommercialmarkets.EcologyLetters9:1115-1126.

ClarkeS,(2008).UseofsharkfintradedatatoestimatehistorictotalsharkremovalsintheAtlanticOcean.Aquat.LivingRes.21:373-381.

ClarkeD.T.andC.Smith(2009):SouthAfricaNationalReport;IOTC-2009-SC-INF12

Clucas,I.(1997)Astudyoftheoptionsforutilizationofbycatchanddiscardsfrommarinecapturefisheries.FAOFisheriesCircularNo.928,59pp

Coelho,Rui,PedroG.Lino&MiguelN.Santos,(2011):At-HaulbackMortalityofElasmobranchsCaughtonthePortugueseLonglineSwordfishFisheryinTheIndianOcean;IOTC-2011-WPEB07-31

Coelho,Rui,MiguelN.Santos&PedroG.Lino(2012):UpdateofthestandardizedcpueseriesformajorsharkspeciescaughtbythePortuguesepelagiclonglinefisheryintheIndianOcean.IOTC–2012–WPEB08–29

Cort,-J.L.(1982)ResultsofthetunaresearchprogramcarriedoutbySpanishbaittunavesselsinSeychelleswaters(July1981-March1982INF.-TEC.-INST.-ESP.-OCEANOGR.1983.no.4,60pp

Dagorn,Laurent,JohnD.Filmalter,FabienForget,MoninJustinAmandè,MartinA.Hall,PeterWilliams,HilarioMurua,JavierAriz,PierreChavance,andNicolasBez(2012a):Targetingbiggerschoolscanreduceecosystemimpactsoffisheries;Can.J.Fish.Aquat.Sci.69:1463–1467


Dagorn,Laurent,JohnFilmalter,FabienForget(2012b):SummaryofresultsonthedevelopmentofmethodstoreducethemortalityofsilkysharksbypurseseinersIOTC–2012–WPEB08–21

Dalzell,P.J.(1993).Smallpelagicfishes.Pp.97-133.In:A.WrightandL.Hill(eds)NearshoremarineresourcesoftheSouthPacific.IPS,Suva,FFA,HoniaraandICOD,Canada.710Pp

DavisM.W.,(2002)Keyprinciplesforunderstandingfishbycatchdiscardmorality.Can.J.Fish.Aquat.Sci.59,1834‐1843

Driggers,WilliamB.,JohnK.Carlson,EnricCortésandG.WalterIngramJr.(2011)Effectsofwireleaderuseandspecies-specificdistributionsonsharkcatchratesoffthesoutheasternUnitedStatesIOTC-2011-SC14-INF08

FisheriesandOceansCanada(2012):PolicyFrameworkonManagingBycatchandDiscards

Fonteneau,A.(2007),;SpeciesCompositionofTunaCatchesTakenbyPurseseiners,WCPFC-SC3-STSWG/IP-7

Fonteneau,Alain,AlainHervé,RenaudPianet,AliciaDelgadodeMolinaandVivecaNordstrom(2009),:Noteupondifficulties,uncertaintiesandpotentialbiasinthemultispeciessamplinganddataprocessingoflargetunas(yellowfin,bigeyeandalbacore)sampledinfreeschoolsbytheIndianOceanandAtlanticpurseseiners,;IOTC-2009-WPTT-Inf01

Fonteneau,Alain(2011):PotentialimpactofGillnetsfisheriesonIndianoceanecosystems;IOTC-2011-WPEB07-INF32

Forget,FabienR.G.,LaurentDagorn,JohnD.Filmalter,MarcSoria,RodneyGovinden(2011):Behaviouroftwomajorbycatchspeciesoftunapurse-seinersatFADs:oceanictriggerfish(Canthidermismaculatus)andrainbowrunner(Elagatisbipinnulata)IOTC-2010-WPEB-11

Furness,R.W.(1999)Willreduceddiscardinghelporharmseabirdpopulations?In:EcosystemApproachesforFisheriesManagement,UniversityofAlaskaSeaGrant,Fairbanks,Alaska,pp.481–489.

Garcia,S.M.(Ed)(2010):SelectiveFishingandBalancedHarvestinRelationtoFisheriesandEcosystemSustainability;ReportofascientificworkshoporganizedbytheIUCN-CEMFisheriesExpertGroup(FEG)andtheEuropeanBureauforConservationandDevelopment(EBCD)inNagoya(Japan),14–16October2010

Gibb,H.A.R.(1929).IbnBattuta:travelsinAsiaandAfrica,1320-1350.Routledge,London.398pp.

Gillett,R.(2011).BycatchinSmall-ScaleTunaFisheries:aGlobalStudy.FisheriesandAquacultureTechnicalPaper.No.560,FoodandAgricultureOrganizationoftheUnitedNations,Rome

Gillett,Robert(2011b):ThePromotionofPole-and-LineTunaFishinginthePacificIslands:EmergingIssuesandLessonsLearned,AReportPreparedfortheForumFisheriesAgency,46pp

Gillett,R.(2012).TheManagementofTunaBaitfisheries:TheResultsofaGlobalStudy.InternationalSeafoodSustainabilityFoundation,WashingtonDC.

Hall,M.A.(1998)Anecologicalviewofthetuna-dolphinproblem.ReviewsinFishBiologyandFisheries8,1–34.

Hall,M.A.,Alverson,D.L.andMetuzals,K.(2000).“Bycatch:Problemsandsolutions”.In:Sheppard,

References


C.R.C.(Ed.)SeasattheMillennium:Anenvironmentalevaluation.Vol.III:GlobalIssuesandProcesses.AmsterdamandOxford:PergamonPressandElsevierScience.ReprintedinMarinePollutionBulletin41(1-6):204–219.

Hall,StephenJ.&BrookeM.Mainprize,(2005):Managingby-catchanddiscards:howmuchprogressarewemakingandhowcanwedobetter?FISHandFISHERIES,2005,6,134–155

Hamer,DerekJ.,SimonJ.ChilderhouseandNickJ.Gales(2011):Odontocetebycatchanddepredationinlonglinefisheries:areviewofavailableliteratureandofpotentialsolutions;IOTC–2011–WPEB07–INF30

Herath,H.L.N.S.(2012):ManagementofsharkfisheryinSriLanka;IOTC–2012–WPEB08–10Rev_1

Hiraoka,YukoandKotaroYokawa(2011):StandardizedCPUEforbluesharkscaughtbyJapanesetunalonglinefisheryintheIndianOcean,1971-1993and1994-2010IOTC-2011-WPEB07-33

Hiraoka,YukoandKotaroYokawa(2012):UpdateofCPUEofbluesharkcaughtbyJapaneselonglinerandestimationofannualcatchseriesintheIndianOceanIOTC–2012–WPEB08–28

HolmesBH,SteinkeDandWardRD,(2009).IdentificationofsharkandrayfinsusingDNAbarcoding.FisheriesResearch95:280-288.

Hutchinson,M.,D.Itano,J.Muir,B.LeroyandK.Holland.2012.Thepost-releaseconditionofFADassociatedsilkysharks(Carcharhinusfalciformis)caughtintunapurseseinegear.WCPFC-SC8-EB-WP-12.Ingram,GW,WBDriggersIII,JKCarlsonandECortés(2011)Effectsofwireleadersonsizeandcatchratesofsharkscapturedonpelagiclonglinegear.In:InternationalSymposiumonCircleHooksinResearch,ManagementandConservation.Miami,Florida,USA.

Inoue,Yukiko,KotaroYokawa,HiroshiMinami,DaisukeOchi,2011:Preliminaryviewofbycatchhotspot:bycatchdistributionintheIOTCareaofthesouthernhemisphere;IOTC-2011-WPEB07-40

IOTC(2001);ReportoftheFourthSessionoftheScientificCommittee;IOTC/S/01/04

IOTC(2007).WorkshoponthedepredationinthetunalonglinefisheriesintheIndianOcean.Report,IndianOceanTunaCommission(IOTC),Victoria,Seychelles,9-10July2007.50pp.

IOTC(2011)ReportoftheFourteenthSessionoftheIOTCScientificCommittee,Mahé,Seychelles,12–17December2011,259pp

IOTC(2011b)StatusofsharksintheIndianOcean;SeventhSessionoftheWorkingPartyonEcosystemsandBycatch,Maldives,24–27October2011IOTC–2011–WPEB07–14

ISSF(2009):StatusoftheWorldFisheriesforTunaSectionC–BycatchesandDiscards,20pp

Itano,D.andV.Restrepo.2011.StatusofthePurseSeineBycatchMitigationProjectandresearchcruisesfundedbytheInternationalSeafoodSustainabilityFoundationwithnotesonthedevelopmentofbestpracticesforthelivereleaseofencircledanimals.WCPFC-SC7/EB-WP-11.

IUCN,(2011).IUCNRedListofThreatenedSpecies.Version2011.www.iucnredlist.org

Itano,D.,J.Muir,M.Hutchinson,andB.Leroy.2012a.OverviewoftheISSFBycatchMitigationResearchCruiseintheWCPO.WCPFC-SC8-EB-WP-11.


Itano,D.,J.Muir,M.Hutchinson,andB.Leroy.2012b.Developmentandtestingofareleasepanelforsharksandnon-targetfinfishinpurseseinegear.WCPFC-SC8-EB-WP-14.

Kelleher,K.(2004)Discardsintheworld’smarinefisheries.Anupdate.FAOFisheriesTechnicalPaper.No.470.Rome,FAO.2005.131p.

Kim,Z.G.KIM,S.I.LEE,D.N.KimandD.W.Lee,(2011):KoreanNationalReporttotheScientificCommitteeoftheIndianOceanTunaCommission,2011;IOTC-2011-SC14-NR14 7

KirbyDS,vanderGeestC,PattersonHM,CheshireKJ,McCloudC,2011,ReviewofIOTCdiscussionsandrecommendationsforsharkconservationintheIndianOcean,ABARESreporttoclientpreparedforAustralianGovernmentDepartmentofAgriculture,FisheriesandForestry,Canberra,September.IOTC-2011-SC14-45

Kerstetter,DW&Graves,JE(2006),“EffectsofcircleversusJ-stylehooksontargetandnon-targetspeciesinapelagiclonglinefishery.”FisheriesResearch,vol.80,pp.239-250.

Lewis,A.D.(1990).TropicalsouthPacifictunabaitfisheries.Pp.10-21.In:S.J.M.BlaberandJ.W.Copland(eds)TunabaitfishintheIndo-Pacificregion:Proceedingsofaworkshop.Honiara,SolomonIslands,11-13December1989.ACIARProceedings,Canberra,No.30:1-211.

LewisonR.L.,CrowderL.,ReadA.&FreemanS.,(2004).Understandingimpactsoffisheriesbycatchonmarinemegafauna.TREE,19,11,598—604

LezamaN.,H.Murua,J.Ruiz,P.Chavance,A.DelgadodeMolina(2011)SpeciescompositionandrichnessofthepelagicecosystembasedonEUPSobserverdataintheWesternIndianOcean;IOTC–2011–WPEB07–5124pp.

Loekkeborg,S.andRobertson,G.(2002)Seabirdandlonglineinteractions:effectsofabird-scaringstreamerlineandlineshooterontheincidentalcaptureofnorthernfulmarsFulmarusglacialis.BiologicalConservation,106,359–364.

Loekkeborg,S.andSkeide,R.(2001)DevicestoAvoidBycatchofBirdsinLonglineFishery.PINROPress,Murmansk

MartenG.andJ.J.Polovina(1982).Acomparativestudyoffishyieldsfromvarioustropicalecosystems.Pp.255-289.

In:D.PaulyandG.I.Murphy(eds)Theoryandmanagementoftropicalfisheries.ICLARMConferenceProceedings9.

ICLARM,ManilaandCSIRO,Cronulla.

Marsac,-F.;Poupon,-J.C.;Potier,-M.;Stequert,-B.(1983)ThelivebaitintheSeychellesIslands:Asynthesis.).RAPP.-SCI.-MISSION-ORSTOM-SEYCHELLES.VICTORIA-MAHE-SEYCHELLES-ORSTOM1983.no.1,68pp

McCoy,M.andR.Gillett(2007).ConsiderationofCatchRetentionasaTunaManagementMeasureintheWesternandCentralPacificOcean.Gillett,PrestonandAssociatesfortheForumFisheriesAgency,Honiara,43pages.

Mees,C.,J.PearceJ.Clarke,OWilsonandA.Carroll(2008):UKnationalreport,IOTC-2008-SC-INF12,IOTCEleventhSessionoftheScientificCommitteeMahé,Seychelles,1-5December2008

References


Moazzam,Muhammad(2012):StatusreportonbycatchoftunagillnetoperationsinPakistan;IOTC–2012–WPEB08–13

MRAG.2012.AreviewofbycatchintheIndianOceangillnettunafleetfocussingonIndiaandSriLanka.ISSFTechnicalReport2012-¬‐05.InternationalSeafoodSustainabilityFoundation,Washington,D.C.,USA.

Muir,J.,D.Itano,M.Hutchinson,B.LeroyandK.Holland.2012.Behavioroftargetandnon-targetspeciesondriftingFADsandwhenencircledbypurseseinegear.WCPFC-SC8-EB-WP-13.

Norris,S.,Hall,M.A.,Melvin,E.F.andParrish,J.K.(2002)Thinkinglikeanocean:ecologicallessonsfrommarinebycatch.ConservationinPractice3,10–19.

Northridge,S.(1991).Driftnetfisheriesandtheirimpactsonnon-targetspecies:aworldwidereview.FisheriesTechnicalPaper320,FoodandAgricultureOrganizationoftheUnitedNations,Rome

O’Connell,CraigP.,DanielC.Abel,EricM.StroudandPatrickH.Rice(2011):Analysisofpermanentmagnetsaselasmobranchbycatchreductiondevicesinhook-and-lineandlonglinetrials;Fish.Bull.109:394–401

Poisson,F.,VernetA.L.,FilmaterJ.D.,GoujonM.,DagornL.(2011):Survivelofsilkysharks(Carcharhinusfalciformis)caughtincidentallyonboardFrenchtropicalpurseseiners:IOTC–2011–WPEB07–28

Ramos-Cartelle,A.,B.García-Cortés,J.OrtízdeUrbina,J.Fernández-Costa,I.González-GonzálezandJ.Mejuto(2012):Standardizedcatchratesoftheoceanicwhitetipshark(Carcharhinuslongimanus)fromobservationsoftheSpanishlonglinefisherytargetingswordfishintheIndianOceanduringthe1998-2011period;IOTC-2012-WPEB08-27

Restrepo,V.(2010).Internationalseafoodsustainabilityfoundationinitiativestodevelopandtestbycatchmitigationoptionsfortropicalpurseseinefisheries.WCPFC-SC6/FT-WP-04.

Robertson,G.,Moe,E.,Haugen,C.andWienecke,B.(2003)Howfastdodemersallonglinessink?FisheriesResearch62,385–388.

Romanov,EvgenyV.(2001):Bycatchinthetunapurse-seinefisheriesofthewesternIndianOcean;Fish.Bull.100(1):90–105(2002),17pp.

RomanovE,BachP,RomanovaN,(2008).PreliminaryestimatesofbycatchesinthewesternequatorialIndianOceaninthetraditionalmultifilamentlonglinegears(1961-1989)IOTCWorkingPartyonEcosystemsandBycatch(WPEB)Bangkok,Thailand.20-22October,2008.18p.

Romanov,2010.Rapportdemissiond’observateur.Navire«Manohal».ProgrammeEuropéen:DataCollectionRégulation(DCR)/IRD.21p.

RomanovE.,BachP.,RabearisoaN.,RabehagasoaN.,FilippiT.,RomanovaN.(2010);PelagicelasmobranchdiversityandabundanceintheIndianOcean:ananalysisoflong-termtrendsfromresearchandfisherieslonglinedata;IOTC-2010-WPEB-16

Schaefer,K.M.andD.W.Fuller.AnOverviewofThe2011ISSF/IATTCResearchCruiseforInvestigatingPotentialSolutionsforReducingFishingMortalityonUndesirableSizesofBigeyeAndYellowfinTunas,andSharks,inPurse-SeineSetsonDriftingFADs.WCPFCScientificCommitteeSeventhRegularSession.9-17August2011.WCPFC-SC7/EB-WP-13.Serafy,JE,Kerstetter,DW&Rice,PH2009,“Cancirclehookusebenefitbillfishes?”FishandFisheries,vol.10,pp.132-142.


Shahifar,Reza(2012):EstimationofbycatchanddiscardinIranianfishingvessels(gillnets)intheIOTCareaofcompetenceduring2012,IOTC–2012–WPEB08–42

Sharp,GaryD.(1979):AreasofpotentiallysuccessfulexploitationoftunasintheIndianOceanwithemphasisonSurfacemethods;Rome,FAO,IOFC/DEV/79/47:51p.www.fao.org/DOCREP/003/X6845E/X6845E08.htm

SheikMamode,A.,2011:BycatchlandingsinMauritiusfor2009/2010;IOTC-2011-WPEB07-20

Stone,Robert,LagiToribau,SariTolvanen(2009);DevelopingSustainableandEquitablePoleandLineFisheriesforSkipjack,GreenpeaceInternational,GPIReferenceJN225

Stoner,AllanW.,StephenM.Kaimmer(2008),;Reducingelasmobranchbycatch:LaboratoryinvestigationofrareearthmetalandmagneticdeterrentswithspinydogfishandPacifichalibutOriginalResearchArticleFisheriesResearch,Volume92,Issues2–3,August2008,Pages162-168

Tan,RaymondR.Ph.D.andAlvinB.Culaba,Ph.D.(2009)EstimatingtheCarbonFootprintofTunaFisheries;CenterforEngineeringandSustainableDevelopmentResearchDeLaSalleUniversity,2401TaftAvenue,1004Manila,Philippines

Tyedmers,P.andR.Parker.(2012).Fuelconsumptionandgreenhousegasemissionsfromglobaltunafisheries:Apreliminaryassessment.ISSFTechnicalReport2012-03.InternationalSeafoodSustainabilityFoundation,McLean,Virginia,USA.

Vega,RandRLicandeo(2009)TheeffectofAmericanandSpanishlonglinesystemsontargetandnon-targetspeciesintheeasternSouthPacificswordfishfishery.FisheriesResearch,98(1–3):22–32.

Ward,P,ELawrence,RDarbyshireandSHindmarsh(2008)Large-scaleexperimentshowsthatnylonleadersreducesharkbycatchandbenefitpelagiclonglinefishers.FisheriesResearch,90(1–3):100–8.

Wilson,J.andM.McCoy(2009).TheEnergyCostsandFishingStudy.In:FisheriesintheEconomiesofPacificIslandCountriesandTerritories.PacificStudiesSeries,AsianDevelopmentBank,WorldBank,ForumFisheriesAgency,SecretariatofthePacificCommunity,andAustralianAgencyforInternationalDevelopment,520pages.

Xu,Liuxiong,XiaojieDai,JiangfengZhu,XiaomingYang,2011:CHINANationalReporttotheScientificCommitteeoftheIndianOceanTunaCommission,2011;IOTC-2011-SC14-NR03

Yokawa,KotaroandYasukoSemba(2012):UpdateofthestandardizedCPUEofoceanicwhitetipshark(Carcharhinuslongimanus)caughtbyJapaneselonglinefisheryintheIndianOcean;IOTC–2012–WPEB08–26

Yokota,K.,M.Kiyota,andH.Minami.2006.Sharkcatchinapelagiclonglinefishery:Comparisonofcircleandtunahooks.FisheriesResearch81:337-341

Zacharia,S.(2007).FisheriesofLakshadweepwithSpecialReferencetoLivelihoodIssues,TechnicalDigest,Issue102007.

Zhou,S.(2008).“Fisheryby-catchanddiscards:apositiveperspectivefromecosystem-basedfisherymanagement”.FishandFisheries9:308–315.

Zhou,Shijie,AnthonyD.M.Smith,AndréE.Punt,AnthonyJ.Richardson,MarkGibbs,ElizabethA.Fulton,SeanPascoe,CatherineBulman,PeterBayliss,andKeithSainsbury(2010)Ecosystem-basedfisheriesmanagementrequiresachangetotheselectivefishingphilosophyPNASMay25,2010vol.107no.219485-9489

AppendixI


APPENDIX I

SpeciesidentifiedasbycatchofthedifferenttunafisheriesintheIndianOcean:PnL=pole-and-line;LL=longline;FS=Freeschool;FO=floatingobjectschool[FAD]

Purse seine IUCNCommon name

Speciesgroup

Family Species name

PnL LL FS FO Sea-mount

Red list

Fishes Balistidae Abalistesstellatus X X -

Fishes Belonidae Ablenneshians - X -

Fishes Pomacentridae Abudefdufvaigiensis X X -

Wahoo Fishes Scombridae Acanthocybiumsolandri X X X

Lancetfish Fishes Alepisauridae Alepisaurusferox X

Fishes Monacanthidae Aluterus monoceros X X -

Bullettuna Fishes Scombridae Auxisrochei X

Frigatetuna Fishes Scombridae Auxisthazard X

Ray'sbream Fishes Bramidae Bramabrama X

Spottedtriggerfish

Fishes Balistidae Canthidermismaculatus

X X X -

Fishes Carangidae Carangoidesortho-grammus

- X -

Fishes Carangidae Carangoidesspp. X

Fishes Carangidae Caranxsexfasciatus X X -

Blue Damselfish

Fishes Pomacentridae Chromisviridis X

Dolfinfish Fishes Coryphaenidae Coryphaenaequiselis X - X -

Dolfinfish Fishes Coryphaenidae Coryphaenahippurus X X X X

Fishes Nomeidae Cubicepscapensis X - -

Driftfish Fishes Nomeidae Cubicepsgracilis X

Mackerel scad

Fishes Carangidae Decapterus macarellus

X X -

Mackerel scad

Fishes Carangidae Decapterus sp. - X -

Pufferfish Fishes Diodontidae Diodonhystrix X X X

Pufferfish Fishes Diodontidae Diodon sp. X X X

Rainbowrunner

Fishes Carangidae Elagatisbipinnulata X X X X X

Shorthead Anchovy

Fishes Engraulididae Encrasicholinahet-eroloba

X

Kawakawa Fishes Scombridae Euthynnusaffinis X X X X X

Silversides/Hardyheads

Fishes Atherinidae X

Cardinal-fishes

Fishes Apogonidae X

Triggerfish Fishes Balistidae FamilyBalistidae X X -

Fishes Belonidae FamilyBelonidae X X -

Fishes Bramidae FamilyBramidae X X -

Fusiliers Fishes Caesionidae X

Fishes Carangidae FamilyCarangidae X X -


Dolphinfish Fishes Coryphaenidae FamilyCoryphaenidae X X X

Fishes Echeneidae FamilyEcheneidae X X -

Fishes Ephippidae FamilyEphippidae - X -

Flyingfish Fishes Exocoetidae FamilyExocoetidae X X -

Fishes Fistularidae FamilyFistularidae X - -

Fishes Molidae FamilyMolidae X - -

Fishes Pomacentridae FamilyPomacentridae - X -

Fishes Scombridae FamilyScombridae - X -

Fishes Sphyraenidae FamilySphyraenidae - X -

Fishes Tertaodontidae FamilyTetraodontidae - X -

Butterflykingfish

Fishes Scombridae Gasterochisma melanpus

X

Snakemackerel

Fishes Gempylidae Gempylusserpens X

Fishes Hexanthidae Hexanthusgriseus X

Skipjack Fishes Scombridae Katsuwonuspelamis X

Fishes Kyphosidae Kyphosus

cinerascens X X X

Fishes Kyphosidae Kyphosusvaigiensis X X -

Fishes Tertaodontidae Lagocephalus lago-cephalus

X X X -

Moonfish Fishes Lampridae Lampris guttatus X - X -

Escolar Fishes Gempylidae Lepidocybiumflavob-runneum

X

FusilierDamselfish

Fishes Pomacentridae Lepidozygoustapeino-soma

X

Fishes Lobotidae Lobotessurinamensis

X X X

Sharptailmola

Fishes Molidae Masturus lanceolatus

X X X -

Oceansun-fish

Fishes Molidae Mola mola X X - -

Fishes Carangidae Naucrates ductor X X X -

Fishes Ephippidae Plataxsp. - X -

Fishes Ephippidae Plataxteira X X -

Fishes Echeneidae Remora australis - X -

Fishes Echeneidae Remora remora X X _

Fishes Echeneidae Remorinaalbescens - X X

Oilfish Fishes Gempylidae Ruvettus pretiosus X - X -

Fishes Scombridae Scomberjaponicus - X -

Spanishmackerel

Fishes Scombridae Scomberomoruscom-merson

X

Fishes Scombridae Scomberomorustritor X - X -

Fishes Carangidae Seriola rivoliana X X X

Barracuda Fishes Sphyraenidae Sphyraenabarracuda X X X -

SilverSprat Fishes Clupeidae Spratelloides gracilis X

BlueSprat Fishes Clupeidae Spratelloides delicatulus

X


Speciesgroup

Family Species name


Red list

AppendixI


Sicklepom-phret

Fishes Bramidae Taractichthysstein-dachneri

X

Snoek Fishes Gempylidae Thyrsitesatun X

Slenderribbonfish

Fishes Trachypteridae Trachipterus ishikawae

X

Fishes Belonidae Tylosuruscrocodilus - X -

Fishes Carangidae Uraspis helvola - X -

Fishes Carangidae Uraspis secunda X X X

Fishes Carangidae Uraspis sp. - X -

Fishes Carangidae Uraspis uraspis X X -

Swordfish Fishes Xiphiidae Xiphias gladius X X X X

Fishes Zanclidae Zancluscornutus X - -

Tunasnei Fishes Scombridae X

Billfishes Istiophoridae FamilyIstiophoridae X X -

Billfishes Istiophoridae Istiophoridae nei X

Sailfish Billfishes Istiophoridae Istiophorusplatypterus X X X X

Blackmarlin Billfishes Istiophoridae Makaira indica X X X -

Bluemarlin Billfishes Istiophoridae Makaira nigricans (=mazara)

X X X -

Shortbillspearfish

Billfishes Istiophoridae Tetrapturus angustirostris

X X X -

Stripedmarlin

Billfishes Istiophoridae Tetrapturusaudax X X X -

Bigeyethresher shark

Sharks Alopiidae Alopias superciliosus X Vulnerable

Commonthresher shark

Sharks Alopiidae Alopias vulpinus X Vulnerable

Sharks Carcharhinidae Carcharhinidaenei X Vulnerable

Coppershark

Sharks Carcharhinidae Carcharhinusbrachyurus

X Near Threatened

Silkyshark Sharks Carcharhinidae Carcharhinusfalciformis X X X X Near Threatened

Galapagosshark

Sharks Carcharhinidae Carcharhinusgalapagensis

X Near Threatened

Blacktipshark

Sharks Carcharhinidae Carcharhinuslimbatus X Near Threatened

Oceanicwhitetipshark

Sharks Carcharhinidae Carcharhinuslongimanus

X X X - Vulnerable

Duskyshark Sharks Carcharhinidae Carcharhinusobscurus

X - X - Vulnerable

Sandbarshark

Sharks Carcharhinidae Carcharhinusplumbeus X Vulnerable

Velvetdog-fish

Sharks Centrophoridae Centrophorusspp X Vulnerable

Sharks Carcharhinidae FamilyCarcharhinidae X X -


Speciesgroup

Family Species name


Red list


Sharks Sphyrnidae FamilySphyrnidae - X -

Tigershark Sharks Carcharhinidae Galeocerdo cuvieri X X - - Near Threatened

Shortfinmakoshark

Sharks Lamnidae Isurusoxyrinchus X - X X Vulnerable

Longfinmakoshark

Sharks Lamnidae Isurus paucus X Vulnerable

Mako sharks nei

Sharks Lamnidae Isurus species X

Porbeagle Sharks Lamnidae Lamna nasus X Vulnerable

Megamouthshark

Sharks Megachasmidae Megachasma pelagios

X - - Vulnerable

Blue shark Sharks Carcharhinidae Prionacegiauca X X - - Near Threatened

Crocodileshark

Sharks Pseudocariidae Pseudocarchariaskamoharai

X

Whale shark Sharks Rhincodontidae Rhincodontypus X X - Near Threatened

Scallopedhammerhead

Sharks Sphyrnidae Sphyrnalewini X X X - Endangered

Smoothhammerhead

Sharks Sphyrnidae Sphyrnazygaena X Endangered

Sharksnei Sharks Sharksnei X Vulnerable

Spottedeagle ray

Rays Myliobatidae Aetobatusnarinari X -

Rays Dasyatidae FamilyDasyatidae X X -

Rays Rhinopteridae FamilyRhinopteridae - X -

Manta Rays Myliobatidae Mantabirostris X X X X

Manta Rays Myliobatidae Manta sp. X - -

Spineraymobula

Rays Myliobatidae Mobulajapanica(=ran-curelli)

X X X

Devilfish Rays Myliobatidae Mobulamobular X X X -

Devilray Rays Myliobatidae Mobulasp. X - X Endangered

Chileandevilray

Rays Myliobatidae Mobulatarapacana(=coilloti)

X X X X

Pelagicstingray

Rays Dasyatidae Pteroplatytrygonviolacea

X X X -

Rays Raysnei Raysnei X

Loggerhead turtle

Turtles Cheloniidae Carettacaretta X - X -

Greenturtle Turtles Cheloniidae Cheloniamydas X - X -

Leatherbackturtle

Turtles Dermochelidae Dermochelyscoriacea

X

Hawksbillturtle

Turtles Cheloniidae Eretmochelysimbricata

X X - Criticallyendangered

Oliveridleyturtle

Turtles Cheloniidae Lepidochelysolivacea

X X - Vulnerable


Speciesgroup

Family Species name


Red list

AppendixI


Southernroyalalba-tross

Birds Diomedidae Diomedea epomorpha

X

Wanderingalbatross

Birds Diomedidae Diomedeasanfordi X

Capepetrel Birds Sulidae Morus capensis X Endangered

PetrelWhitechinned

Birds Procellariidae Procellariaaequinoctialis

X

Flesh-footedshearwater

Birds Procellariidae Puffinuscarneipes X

Buller’salbatross

Birds Diomedidae Thalassarchebulleri X LeastCon-cern

Shyalba-tross

Birds Diomedidae Thalassarche cauta X Near Threat

Yellownosedalbatross

Birds Diomedidae Thalassarche chlororhynchos

X Endangered

Greyheadedalbatross

Birds Diomedidae Thalassarche chrysostoma

X Near Threat-ened

Black-browedalbatross

Birds Diomedidae Thalassarche melanophrys

X Endangered

White-cappedalbatross

Birds Diomedidae Thalassarche steadi X Vulnerable

Unidentifiedalbatrosses

Birds Diomedidae X

Unidentifiedgannets&boobys

Birds Procellariidae X

Unidentifiedpetrels

Birds Procellariidae X

Finwhale Cetaceans Balaenopteridae Balaenoptera physalus

X X -

Commondolphin

Cetaceans Dephinidae Delphinus capensis X Endangered

Pygmykillerwhale

Cetaceans Delphinidae Feresa attenuata X

Risso'sdolphin

Cetaceans Delphinidae Grampus griseus X

Falsekillerwhale

Cetaceans Globicephalidae Pseudorcacrassidens X - X - LeastCon-cern

Spinnerdolphin

Cetaceans Delphinidae Stenella longirostris X

Others nei

X


Speciesgroup

Family Species name


Red list

LIST OF PUBLICATIONS – LISTE DES PUBLICATIONSSmartFishProgramme

1. ReportoftheInception/FocalPointMeetingoftheSmartFishProgramme–FlicenFlac,Mauritius,15th-16thJune2011.REPORT/RAPPORT:SF/2011/01.August/Août2011.SmartFishProgramme.IndianOceanCommission.

2. ReportoftheFirstSteeringCommitteeMeetingoftheSmartFishProgramme–FlicenFlac,Mauritius,17thJune2011.REPORT/RAPPORT:SF/2011/02.August/Août2011.SmartFishProgrammeIndianOceanCommission.

3. RapportdelaréuniondeprésentationduprogrammeSmartFishauxpointsfocaux–FlicenFlac,IleMaurice,15-16juin2011.REPORT/RAPPORT:SF/2011/03.August/Août2011.SmartFishProgramme.IndianOceanCommission.

4. Eco-CertificationfortheTunaIndustry,TechnicalAssistanceforImplementationofaRegionalFisheriesStrategyforESA-IO(IRFS).REPORT/RAPPORT:SF/2011/04.May2011.SmartFishProgramme.IndianOceanCommission.

5. RegionalMarketAssessment(SupplyandDemand).REPORT/RAPPORT:SF/2012/05.March/Mars2012.SmartFishProgramme.IndianOceanCommission.

6. TradeAssessmentStudy.REPORT/RAPPORT:SF/2012/06.March/Mars2012.SmartFishProgramme.IndianOceanCommission.

7. GouvernancedesPêchesMaritimesdansl’Ouestdel’OcéanIndien.REPORT/RAPPORT:SF/2012/07.June/Juin2012.SmartFishProgramme.IndianOceanCommission.

8. ValueChainAssessmentoftheArtisanalFisheries–Mauritius.REPORT/RAPPORT:SF/2012/08.June/Juin2012.SmartFishProgramme.IndianOceanCommission.

9. KenyaFisheriesGovernance.REPORT/RAPPORT:SF/2012/09.June/Juin2012.SmartFishProgramme.IndianOceanCommission.

10. TrainingNeedsAnalysis–QualityandHygiene:REPORT/RAPPORT:SF/2012/10.June/Juin2012.SmartFishProgramme.IndianOceanCommission.

11. AReviewofSomalia’s&(Semi-AutonomousRegions)FisheriesLegislationandManagement. REPORTRAPPORT:SF/2012/11.June/Juin2012SmartFishProgramme.IndianOceanCommission.

12. AssessmentofIUUActivitiesOnLakeVictoria.REPORT/RAPPORT:SF/2012/12.June/Juin2012SmartFishProgramme.IndianOceanCommission.

13. ReviewOfTheLegalFrameworkfortheESA-IORegion.REPORT/RAPPORT:SF/2012/13.June/Juin2012SmartFishProgramme.IndianOceanCommission.

14. ComprehensivecapacityreviewtoimplementeffectiveMCSintheESA-IORegion.REPORT/RAPPORT:SF/2012/14.June/Juin2012SmartFishProgramme.IndianOceanCommission.

15. AssessmentofIUUFishinginLakeTanganyika.REPORT/RAPPORT:SF/2012/15.June/Juin

2012SmartFishProgramme.IndianOceanCommission.

16. Spirulina – A Livelihood and a Business Venture.REPORT/RAPPORT:SF/2012/16.SmartFishProgramme.June/Juin2012IndianOceanCommission.

17.DiversificationStudy(Eco-TourismandRecreationalFisheries).REPORT/RAPPORT:SF/2012/17.June/Juin2012SmartFishProgramme.IndianOceanCommission.

18. ValueChainAnalysisofFisheriesSectorforRodrigues.REPORT/RAPPORT:SF/2012/18.June/Juin2012SmartFishProgramme.IndianOceanCommission.

19. DagaaValueChainAnalysisandProposalforTradeDevelopment.REPORT/RAPPORT:SF/2012/19.June/Juin2012SmartFishProgramme.IndianOceanCommission.

20. OperationalizationofFishAuctionMarket.(FeasibilityStudy).REPORT/RAPPORT:SF/2011/20.December/Décembre2011SmartFishProgramme.IndianOceanCommission.

21. OptionstoReduceIUUFishinginKenya,Tanzania,UgandaandZanzibar:REPORT/RAPPORT:SF/2012/21.August/Août2012SmartFishProgramme.IndianOceanCommission.

22. RevitalizationofFisheriesResearchinMauritius.REPORT/RAPPORT:SF/2012/22.August/Août2012SmartFishProgramme.IndianOceanCommission.

23. PreparationofDraftKenyaFisheriesManagementandDevelopmentBill:REPORT/RAPPORT:SF/2012/23.August/Août2012SmartFishProgramme.IndianOceanCommission.

24. UneAnalyseGlobaledelaChaîneD’approvisionnementdelaPêcherieduCrabedeMangrove(Scyllaserrate)àMadagasar.REPORT/RAPPORT:SF/2012/24.August/Août2012SmartFishProgramme.IndianOceanCommission.

25. AnalyseGlobaledelaGouvernanceetdelachaîneD’approvisionnementdelaPêcherieduconcombredemeràMadagasar.REPORT/RAPPORT:SF/2012/25.August/Août2012SmartFishProgramme.IndianOceanCommission.

26. ProcessingandMarketingofSmall-SizedPelagicsinEasternandSouthernAfrica.REPORT/RAPPORT:SF/2012/26.August/Août2012SmartFishProgramme.IndianOceanCommission.

27.ReportoftheSecondSteeringCommitteeMeetingoftheSmartFishProgramme.REPORT/RAPPORT:SF/2011/27.August/Août2012.SmartFishProgrammeIndianOceanCommission.

28. TheFarmingofSeaweeds.REPORT/RAPPORT:SF/2011/28.August/Août2012.SmartFishProgrammeIndianOceanCommission.

29. Cultured’AlguesMarines.REPORT/RAPPORT:SF/2011/29.August/Août2012.SmartFishProgrammeIndianOceanCommission.

30. ReportoftheFocalPointMeetingoftheSmartFishProgramme–Livingstone,Zambia,28th–29thFebruary2012.REPORT/RAPPORT:SF/2011/30.August/Août2012SmartFishProgramme.IndianOceanCommission.

31. Appuial’Elaborationd’uneStrategieNationaledeBonneGouvernancedesPechesMaritimesaMadagascar.REPORT/RAPPORT:SF/2012/31.June/Juin2012SmartFishProgramme.IndianOceanCommission.

32. AReviewofBycatchandDiscardIssuesinIndianOceanTunaFisheries.REPORT/RAPPORT:SF/2013/32.2012SmartFishProgramme.IndianOceanCommission.

Documents

A review of bycatch and discard issues in Indian Ocean tuna fisheries