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HarryV.Strehlow
MarineRecrea*onalFisheries-DataCollec*onHarryV.Strehlow1&KieranHyder21ThünenIns*tuteofBal*cSeaFisheries2CefasLowesto?
Athens,06.10.2015
HarryV.Strehlow
Whyisrecrea>onalfisheriesimportant?
06.10.2015 MEDAC–Recrea*onalFisheriesPage2
• Highvalue–spendbillions€
• Largenumbers–usersofthemarineenvironment
• Removals–impactonachievingmanagementobjec*ves(MSY)
• Management&alloca*onofresourcesbetweensectors
Hyderetal.(2014).ICESINSIGHT51:8-15
HarryV.Strehlow
EuropeanRSF:numbers,par>cipa>on&effort
06.10.2015 MEDAC–Recrea*onalFisheriesPage3
Category Total Atlan*c MedNumbers(millions) 8.00(-) 6.02(+/-) 1.98(---)Par*cipa*on(%) 1.53 1.71 1.16Ac*vity(milliondays) 47.9(-) 39.5(+/-) 12.3(---)
HarryV.Strehlow
EuropeanRSF:directexpenditure
06.10.2015 MEDAC–Recrea*onalFisheriesPage4
Category Total Atlan*c MedExpenditure(billion€) 5.18(--)4.51(+/-) 0.67(---)Spendperangler(€) 654 755 344
HarryV.Strehlow
Legisla>on
06.10.2015 MEDAC–Recrea*onalFisheriesPage5
EuropeanMemberStatesobligedtocollectrecrea*onalfisheriesdata:
- (EC)No1639/2001- (EC)2008/949- 2010/93/EU- C(2013)5243
Ø cod,salmon,bluefintuna,eel,sharks,seabass
Ø Recommeda*onsfromICESEGsWGRFSandWGBAST⇒seatrout,Europeanlobster,pollackgroupers,Sparidae,Cephalopods
HarryV.Strehlow
Terminology
06.10.2015 MEDAC–Recrea*onalFisheriesPage6
Defini*on:(ICESWGRFS)
Recrea&onalfishingisthecaptureora3emptedcaptureoflivingaqua&cresourcesmainlyforleisureand/orpersonalconsump1on.Thiscoversac1vefishingmethodsincludingline,spear,andhand–gathering,andpassivefishingmethodsincludingnets,traps,pots,andset–lines.
Recrea*onalfishingac*vi*esarecarriedoutfromdifferentplahorms:
- land-based- sea-based
Mediterranean:EC1967/2006Ar*cle17
Theuseofnets…shallbeprohibitedforleisurefisheries.
HarryV.Strehlow
Challengesfordatacollec>on
06.10.2015 MEDAC–Recrea*onalFisheriesPage7
Datagapsàrecrea>onalfisheriesdatapatchyand/orlackingcompletely!1. nocentralregistra*onofrecrea*onalfishers
2. recrea*onalcatchesnotdocumented
3. recrea*onalfishersfishinremoteandhardtoaccessareas
4. Surveysdifficult&expensive
5. Manycountriesexploitthesamestock
HarryV.Strehlow
Fishingsurveymethods
06.10.2015 MEDAC–Recrea*onalFisheriesPage8
• Challengingstats(design-basedprobabilitysampling)àneedanexpert
• Lowpar*cipa*onrateàdifficulttogetarepresenta*vesample
• Differentdesigns:
- List(e.g.licence)–sampleatrandom&recruitpanel,thenraisetopopula*on
- Nolist–separatesurveysofeffort&catchperuniteffort
HarryV.Strehlow
Surveydesignandbias
06.10.2015 MEDAC–Recrea*onalFisheriesPage9
• Coverage
• Self-selec*on
• Non-response
• Recall
• Avidity
• Speciesiden*fica*on(highvaluespecies)
• Inclusionprobability
• Rounding/digit
• Telescoping,Pres*ge
• Fluctua*on(drop-outs/drop-ins)
HarryV.Strehlow
Exkurs:surveydesignandbias
06.10.2015 MEDAC–Recrea*onalFisheriesSeite10
Biasmayoccuronmanylevels:
1.Surveydesign
• Doesmysamplingframecoverthetargetpopula*on?àcoverageerror,e.g.tourists,illegalfishersetc
• Ismysamplingprocedureprobabilitybased?àe.g.self-selec*onbias,over-andunderes*ma*on
HarryV.Strehlow
Exkurs:surveydesignandbias
06.10.2015 MEDAC–Recrea*onalFisheriesSeite11
Biasmayoccuronmanylevels:
2.Implementa>on
• Arethereprotocolsfortheselec*onofsubsamples?àSelec*onerror,e.g.individuals,*mes,boatsetc
• Areresponseratesrecordedandevaluated?ànonresponsebias
• Istherecallperiodappropriate?àrecallbias;e.g.doesrecallperiodmatchfishingseason
• Speciesiden*fica*on,high-valuespecies
HarryV.Strehlow
Exkurs:surveydesignandbias
06.10.2015 MEDAC–Recrea*onalFisheriesSeite12
Biasmayoccuronmanylevels:
3.Analysis
• Doesthees*ma*onprocedurefollowthesurveydesign?àInclusionprobability,e.g.accesspointssampledwiththesameprobability
• Hasthedatabeenweighted?àcorrec*onfornonresponse/aviditybias
• Havedrop-insordrop-outsbeenconsidered?àfluctua*onbias
HarryV.Strehlow
Recrea>onalfisherydatause
06.10.2015 MEDAC–Recrea*onalFisheriesSeite13
Ø Inclusioninstockassessments
Ø Designandevalua*onofmanagementmeasures(e.g.baglimit)
Ø Designandevalua*onofmanagementplansandstrategies
Ø Marinespa*alplanning
⇒ Co-Management
(recrea*onal&commercialfishery)
HarryV.Strehlow
Managementparadox
06.10.2015 MEDAC–Recrea*onalFisheriesSeite14
MaximumTotalSa*sfac*on(MTS) MaximumSustainableYield(MSY)
VS
Compe*ngobjec*vesarenotalwayscompa*ble,somayrequiretrade-offsbetweensectors
HarryV.Strehlow
Endusersofrecrea>onalfisherydata
06.10.2015 MEDAC–Recrea*onalFisheriesSeite15
Ø ICESexpertgroups(WGRFS,WGNAS,WGBAST,WGBFAS,WGCSE,WGEEL)
Ø EUCommission(DGMARE,DGEnvironment)
Ø Na*onalGovernments
Ø Na*onalandinterna*onalrecrea*onalfishingbodies
Ø Na*onalandinterna*onalcommercialfisheriesbodies
Ø AdvisoryCouncils(e.g.MEDAC,Bal*cSeaAC,NorthSeaAC)
Ø …
HarryV.Strehlow
Whatrecrea>onalfisherydataisneeded...
06.10.2015 MEDAC–Recrea*onalFisheriesSeite16
…tosupporttheCFP?
Es&ma&onofrecrea&onalfisherycatches
• totalnumberofrecrea*onalfishers,charterboats,fishingtripsetc
• CPUE(orcatchperpersonorperboat)
• Biologicaldataoncatches–sizeoragecomposi*on
• Demographicandavidity(frequencyoffishing)data
Economicvalueofrecrea&onalfishing
• Directexpendituredatabyspendcategories
• Marginalvaluesassociatedwithachangeinstock
HarryV.Strehlow
Typesofsurveys
06.10.2015 MEDAC–Recrea*onalFisheriesPage17
Screeningsurvey
• samplefromabroadcoverageframelikeresiden*alhouseholds• Recruitfishingpar*cipantsàpanelsurvey
Off-site Pros Cons
RandomDigitDialing(RDD)
• Completecoveragepossible
• Accurateeffortdata
• Mobilephonesmaybeexcluded• Expensive• Poten*alnonresponse
Mailsurvey • Mostcompletecoveragepossible
• Cheap
• Inefficient• Highnonresponse
Online • Easy• Cheap
• Fishingbehaviourmaynotmatchgeneralpopula*on
HarryV.Strehlow
Typesofsurveys
06.10.2015 MEDAC–Recrea*onalFisheriesPage18
On-site Pros Cons
Accesspoint(fixedpoint)interceptsurvey
• Highpar*cipa*onrate• Norecallbias• Completedfishingday• Accuratecatchdata
• Possibleundercoveragebias
• Expensive
Roving(diffusedpoint)creelsurvey
• Highpar*cipa*onrates• Norecallbias
• Uncompletedfishingday• Expensive
Visual Pros Cons
Aerial/boatsurvey • Coverslargeareas• Usefullforheatmaps
• Veryexpensive• Onlyforeffort
Camerasurvey • Inexpensive• Coversen*refishingday
• Vandalism• Weather
HarryV.Strehlow
Recommenda>ons
06.10.2015 MEDAC–Recrea*onalFisheriesPage19
Ø Regionalcoopera*onbetweencountriesisneeded
Ø Adoptdefini*onforMediterranean
Ø Combina*onofon-siteandoff-siteapproaches
Ø Mul*speciesdatashouldbecollected
Ø Includeeconomicvalueandsocialbenefits(every5years)
Ø Datacollec*ondefinedoncase-by-casebasis
Ø Samplingwithcommercialsmall-scalefisheriessurveys
Ø SeekexpertadvicefromICES
HarryV.Strehlow06.10.2015 MEDAC–Recrea*onalFisheriesSeite20
Thankyou!
harry.strehlow@*.bund.de
WGRFSistheICESWorkingGrouponRecrea*onalFisheriesSurveys:
hsp://www.ices.dk/community/groups/Pages/WGRFS.aspx
WeareseekingnewmembersintheMediterranean!