Download SNAPPER Preparing.fisheries.for.climate.change

South.East.Australian.Program
Preparing.fisheries.for.climate.change
SNAPPER fact sheet
Temperatures.recorded.off.the.east.coast.of.Tasmania.over.the.last.
7j.years.have.shown.that.this.region.is.warming.at.2V8.times.the.
global.averageV.
Over.the.next.centuryQ.the.marine.systems.of.southWeast.Australia.are.
expected.to.continue.exhibiting.some.of.the.largest.climateWdriven.
changes.in.the.Southern.HemisphereQ.with.substantial.changes.to.
ecosystemsV.The.subsequent.flowWon.effects.to.communities.and.
businesses.will.dependQ.in.partQ.on.how.well.fishing.industries.and.
resource.managers.can.adapt.to.these.challengesV.
Snapper.was.one.of.four.case.study.fisheries.selected.to.identify.the.likely.effects.of.climate.change.on.
fisheries.in.southWeast.AustraliaQ.and.to.evaluate.how.well.fishery.assessment.and.management.
frameworks.may.perform.given.expected.future.environmental.changeV
.
The fishery
....Snapper.qChrysophrys auratusk.is.a.
largeQ.longWlivedQ.demersal.finfish.
species.that.is.distributed.throughout.
coastal.waters.around.the.southern.two.
thirds.of.the.Australian.mainlandV.The.
species.supports.significant.commercial.
and.recreational.fisheries.in.each.of.the.
mainland.states.of.QldQ.NSWQ.VicQ.SA.
and.WAV.
.
In.the.different.commercial.fisheries.and.
jurisdictionsQ.snapper.are.targeted.with.
a.number.of.different.gear.types.that.
include.handlinesQ.longlinesQ.haul.seinesQ.
fish.traps.and.demersal.trawlsV..In.
recent.yearsQ.the.national.annual.
commercial.catch.has.varied.from.1Q6jj.
to.6Qjjj.tV..The.commercial.sector.
dominates.catches.in.SA.and.NSWQ.and
the.recreational.sector.dominates.
catches.in.Queensland.and.VictoriaV...
The.various.StateWbased.fisheries.are.
managed.independently.of.each.other.
through.different.regulationsV
About the case study
....Snapper.was.selected.as.a.case.
study.species.to.examine.the.likely.
effects.of.climate.change.because.of.its.
high.commercial.value.and.recreational.
significanceQ.and.because.it.is.
distributed.over.a.broad.latitudinal.
rangeV..FurthermoreQ.it.was.considered.
that.this.case.study.would.provide.
useful.insight.into.how.fisheries.can.
adapt.to.change.when.there.are.
changes.in.the.distribution.of.speciesV
Two.significant.vulnerabilities.of.
snapper.to.climate.change.were.
identifiedV..FirstQ.the.number.of.new.
individuals.surviving.and.entering.the.
fishery.each.year.qnew.recruitsk.in.SA.
and.Vic.is.highly.variable.and.
ultimately.drives.population.biomass.
and.fishery.productivityV..ConsequentlyQ.
for.this.project.we.considered.
environmental.variables.that.are.likely.
to.be.influenced.by.climate.change.and.
that.might.impact.recruitment.dynamicsV..
The.second.potential.vulnerability.to.
climate.change.relates.to.the.
considerable.latitudinal.variation.in.the.
timing.of.the.reproductive.season.of.
snapper.for.which.the.environmental.
cues.remain.poorly.understoodV..
Key effects of climate change
qqqqRecruitmentqvariabilityqofqsnapperqisqnowqthoughtqtoqbeqdrivenqbyq
variableqsurvivorshipqofqtheqearlyqstageqlarvaeNqqInterQannualq
variabilityqofqsuchqsurvivorshipqisqhoweverqnotqaqsimpleqrelationshipq
withqphysicalqfactorsNqqVariousqenvironmentalqfactorsqincludingqwaterq
temperature0qriverqflow0qassociatedqnutrientqinputqregimesqandq
planktonqfoodqchainqdynamicsqinteractqtoqdetermineqtheqoptimalqtimeq
periodsqforqlarvalqsurvivalqandqsurvivalqratesNqTheqcomplexityqofqthisq
systemqcomplicatesqtheqpossibilityqofqdevelopingqsufficientq
understandingqtoqpredictqtheqconsequencesqofqclimateqchangeqonq
recruitmentqdynamicsN
q
Ourqreviewqofqsnapperqspawningqbehaviourqinqrelationqtoqseaqsurfaceq
temperatureq°SSTCqshowedqthatqsnapperqgenerallyqspawnqwhenqSSTqisq
betweenqF8qtoqPP°CNqqThisqtemperatureqrangeqlargelyqcorrespondsqtoq
theqexperimentallyqdeterminedqrangeqofqphysiologicalqtolerancesqforq
survivalqofqsnapperqeggsqandqlarvaeNq
Wequsedqforecastqmodelingqtoqassessqhowqtheqtemporalqwindowqforq
thisqoptimalqspawningqtemperatureqregimeqmayqchangeqatqdifferentq
placesqoverqtheqnextq5HqyearsNqqTheqresultsqindicatedqthatqinqtheqfutureq
forqregionsqsuchqasqQld0qnorthernqNSW0qandqtheqnorthernqgulfsqofqSA0q
thereqmayqbeqnoqperiodqduringqtheqyearqwhenqtheqSSTqfallsqwithinqtheq
toleratedqtemperatureqrangeNqqThisqmayqmeanqthatqsnapperqcannotq
maintainqviable0qselfQrecruitingqpopulationsqinqtheseqregionsNq
q
Inqcontrast0qSSTqregimesqinqnorthernqandqeasternqTasmaniaqareq
predictedqtoqbecomeqmoreqsuitableqforqsnapperqspawningqasqtheseq
regionsqcontinueqtoqwarmNqqConsequently0qinqtheqfutureqtheqbroadQ
scaleqpatternsqofqdistributionqandqabundanceqofqsnapperqdownqtheq
eastqcoastqofqAustraliaqmayqwellqchangeqdueqtoqtheqchangesqinqSSTq
regimes0qasqaqdirectqconsequenceqofqtheqphysiologicalqtoleranceq
rangesqofqtheqeggsqandqlarvaeNqq
Key unknowns in regard to climate change
qqqqCommercialqfisheryqmonitoringqprogramsqareqestablishedqinqeachq
ofqtheqmainlandqstates0qcollectingqcommercialqcatchqandqeffortqdataNqq
Ifqmaintained0qtheseqshouldqbeqsufficientqtoqdetectqsignificantqchangesq
inqtheqdistributionqandqabundanceqofqsnapperqthatqmayqresultqfromq
temporalqorqspatialqchangesqinqspawningqsuccessN
qq
However0qmonitoringqwouldqneedqtoqbeqintroducedqtoqdetectq
predictedqincreasesqinqabundanceqinqTasmanianqwatersNqFurthermore0q
thereqisqlimitedqdataqonqreproductionqofqsnapperqalongqtheqcentralq
andqsouthernqNSWqcoast0qanqareaqwhereqsnapperqreproduction0q
biomassqandqfishingqopportunitiesqcouldqpotentiallyqincreaseqinqtheq
futureqdueqtoqchangesqinqSSTqregimesN
Inqtheqbayqandqgulfqspawningqstocksq°iNeNqSAqandqwesternqVictoriaQ
PortqPhillipCqenhancedqcollectionqofqdataqrelatingqtoqtheqdynamicsqinq
nutrientqsupply0qplanktonqassemblagesqandqsnapperqrecruitmentqareq
necessaryqforqtheqmonitoringqofqeffectsqofqclimateqchangeqonq
recruitmentqvariabilityqandqultimatelyqstockqproductivityNqItqisqlikelyqqq
thatjmorejadvancedjapproachesj
includingjecosystemjorjbiophysicalj
modelsjwilljbejrequiredjtojmakej
predictionsjonjclimatejeffectsjonj
snapperjrecruitmentjregimesjinj
thesejshelteredjwaterjspawningj
andjnurseryjareas.j
Responding to change
Existingjcapacityjforjthejfisheryj
tojadapt
jjjjjThejmostjlikelyjeffectsjofjclimatej
changejarejchangesjinjdistributionjandj
abundancejofjadultjsnapperjthatjwillj
affectjfisheryjproductivityjatjjlocaljasj
welljasjlargerjspatialjscales.jjThej
tractablejadaptationsjtojsuchjchangesj
arejlimitedjbutjinclude:jshiftingjfishingj
operationsjtojnewjtimesjorjplaces;j
increasejorjdecreasejtargetjeffortj
appropriately;jorjifjoperatingjinjaj
multi-speciesjfishery,jshiftjeffortjontoj
otherjspecies.jAjbarrierjtojadaptionj
mayjincludejmulti-jurisdictionalj
management,jforjexamplejifjfishersj
cannotjfollowjshiftsjinjsnapperj
distributionjacrossjStatejborders.jjj
Optionsjforjimprovingjfisheryj
assessmentjframeworks
Therejarejajnumberjofjoptionsjforj
improvingjassessmentjframeworksjforj
snapper.jjThesejinclude:
establishingjajmeansjbyjwhichj
monitoring,jassessmentjandj
managementjofjcrossjurisdictionaljsnapperjstocksjcanj
bejachieved
establishingjfisheryjindependentj
measuresjofjfishablejbiomass,j
andjthereforejmovingjawayjfromj
indicatorsjthatjarejsubjectjtojthej
influencejofjfisherjbehavior,jandj
changesjinjfishjbehaviorjandj
distribution
betterjmonitoringjofjthejcatchjandj
effortjbyjthejrecreationaljsector
j
developingjharvestjstrategiesjthatj
involvejbothjthejrecreationaljandj
commercialjsectorsjandjtakejintoj
accountjsocio-economicjobjectivesj
asjwelljasjbiologicaljsustainabilityj
andjenvironmentaljeffectsjonj
productivity.
Possiblejplannedjadaptationsj
tojconsiderjinjthejfuture
Tojbetterjpreparejforjfuturej
changes,jitjmayjbejbeneficialjto:
implementjsingle-stock,jcrossjurisdictionaljassessmentsjforj
thejappropriatejstocks
increasejmonitoringjtojallowj
detectionjofjchangesjinjpatternsj
ofjdistributionjandjabundance,j
suchjasjinjTasmanianjwatersjandj
tojmanagejsuchjstocksj
appropriatelyjtojallowj
establishmentjofjbreedingj
populations.jMonitoringjofjthej
broaderjecosystemjshouldjalsoj
bejconsideredjtojallowj
understandingjofjhowjsnapperj
arejfittingjintojthejexistingj
ecosystem.
undertakejre-stockingjofjareasj
thatjhavejbeenjnegativelyj
impactedj)i.e.jprolongedjperiodsj
ofjrecruitmentjfailure)
implementjmeasuresjtojprotectjorj
enhancejparticularlyjsignificantj
areasjofjhabitatjorjenhancej
habitatsjwithjartificialjreefsjinj
otherjareasjwherejappropriate.
qqqqq
Barriers to change
qqqqEstablishingqcross-jurisdictionalqregulationsqwillqbeqdifficult,qstockingqorqrestockingqisqexpensiveqandqmayqalsoqcreateqissuesqwithqgeneticsqandqpossibleq
disease.qqAdditionalqmonitoringqorqintroducingqfisheryqindependentqmonitoringqisq
alsoqexpensiveqandqsoqanyqplannedqchangesqtoqassessmentqorqmonitoringq
frameworksqwillqneedqtoqbeqcarefullyqconsideredqbyqallqstakeholdersqinvolved.qqq
Knowledge/data requirements into the future
qqqqFurtherqinvestigationsqofqrecruitmentqvariabilityqareqrequiredqtoqenhanceqourq
understandingqofqtheqcomplexqinteractionsqbetweenqbiologicalqprocessesqandqtheq
biologicalqandqphysicalqenvironment.qqThen,qinqorderqtoqbetterqunderstandqtheq
effectsqofqclimateqchange,qweqwillqneedqbetterqpredictionsqofqrainfall,qandqriverq
flowqregimesqforqplacesqlikeqPortqPhillipqBay.qSuchqpredictionsqwouldqthenqbequsedq
asqinputqtoqbiophysicalqmodelsqthatqareqcurrentlyqunderqdevelopmentqtoqprovideq
betterqquantitativeqmeasuresqofqtheqeffectsqofqvariableqclimateqonqrecruitmentqandq
fisheryqproductivity.qForqtheqeastqcoastqstockq(withqoceanicqspawning),qimprovedq
oceanographicqforecastqmodellingqisqimportantqforqunderstandingqtheqimplicationsq
ofqchangesqinqtheqEastqAustralianqCurrentqtoqlarvalqdispersal,qsurvivalqandqregionalq
recruitmentqpatterns.qq
http:44frdc7com7au4environment4climate_change4I
Ensuring that the fisheries of south-east Australia adapt effectively to
climate change will require robust scientific understanding and the
development of management systems that will allow negative impacts to
be mitigated and opportunities that arise to be seized.
PaulIHamer8IDEPI
Paul7Hamer@depi7vic7gov7au
26fIMI5_58I/_88
http:44www7redmap7org7au4
AnthonyIFowler8IPIRSA0SARDI
Anthony7Fowler@sa7gov7au
26fI8I8_/7I54M_
GrettaIPecl8IIMAS
Gretta7Pecl@utas7edu7au
26fIMI6__7I7_77
PhotoIcredits:I
AnthonyIFowler8I
ElsaIGärtner8II
PaulIHamer8I
AndrewIPender8I
RickIStuart0
SmithIandI
SARDI