Download - Oral presentation at National Conference on Beach Preservation Technology (2012)

Examiningdifferentbeachnourishmentdesignstounderstandchangesinmarineturtlenesting

AllisonHaysandLlewellynEhrhartUniversityofCentralFlorida

Marineturtles

LoggerheadFederallythreatened

73,702nests

GreenturtleFederallyendangered

13,225nests

Marineturtles

DataandmapcopyrightSTC

Marineturtles

Marineturtles

GeneticallydistinctregionalrookerygroupingsShamblinetal2011

Loop Bodypit Eggchamber

Non‐nestingemergence(Falsecrawl)

Marineturtles

Marineturtles

•  Capitalbreeders– Storednutrients

•  Unexpectedfalsecrawls?

Marineturtles

Photo:KellyMartin

Beachnourishment

•  Temporaryinloggerheadnestingsuccessrates(#nests/total#emergences)

•  1greenturtlestudy•  Nonewithalternatetemplatedesigns

BrevardCounty,FL

DDR

ArchieCarrNWR

Nourishmentdesigns

Full‐scalerestoration(FSR)

DDR

2005,2010

ArchieCarrNWR

Photo:TownofLongboatKey

FSR

Nourishmentdesigns

Full‐scalerestoration(FSR)

2005,2010 2005,2006,2008,2009

Dunerestoration(DR)

Photo:TownofLongboatKey

Methods

•  Before‐After‐Control‐ImpactPairedSeriesModel

•  Pairedt‐test•  Holm’stest

CONTROL IMPACT DELTA

BEFOREDAY1

(1997‐2001average)

60% 60% 0%

AFTERDAY1

(2005)60% 10% 50%

DRResultsLoggerhead Greenturtle

YOC=yearofconstructionErrorbars=SE*significance<0.05,**<0.01,and***<0.001

Nestin

gsuccessrate

Nestin

gsuccessrate

FullScaleRestorationResultsLoggerhead Greenturtle

Nestin

gsuccessrate

Nestin

gsuccessrate

Nestin

gsuccessrate

Nestin

gsuccessrate

YOC=yearofconstructionErrorbars=SE*significance<0.05,**<0.01,and***<0.001

Loggerheadeffectsizes

YOC 1YEARPOSTEffectsize

p‐value Effectsize

p‐value

DR ‐0.11 >0.05 ‐0.05 <0.001*FSR ‐0.13 ‐0.16

Greenturtleeffectsizes

YOC 1YEARPOSTEffectsize

p‐value Effectsize

p‐value

DR ‐0.15 0.002* ‐0.08 <0.001*FSR ‐0.29 ‐0.32

Objectives

•  Objective1:Determinebeachcharacteristicsthatserveasnestingcues

•  Objective2:Determineifalteringkeycharacteristicsthroughbeachrestorationaffectstheirroleasnestingcues

Studysites

•  photos

•  6studysites(3treatments)–  Natural–  DR–  FSR:flat

Studysites

•  photos

•  6studysites(3treatments)–  Natural–  DR–  FSR:sloped

Photo:EcologicalAssociates,Inc

Methods•  Loggerheads•  Nests•  Unobstructedloopingfalsecrawls

Methods

Objective1:StatisticsNestingcues

•  Logisticregressionmodelselection– Beachspecific:

•  Beachslope•  Beachwidth•  Moisturecontent•  Grainsize

– Turtlespecific:•  Slopewhereturtlestopped•  Distancetraveled

– Createmodelstopredictifturtlenests

Objective1:ResultsNestingcues

•  R2=0.75•  Beachslopeandwidth•  Sandmoisturecontentandgrainsize

•  Distanceturtletraveled•  Slopewhereturtlestopped

Objectives

•  Objective1:Determinebeachcharacteristicsthatserveasnestingcues– Beachslopeandwidth– Sandmoisturecontentandgrainsize

Objectives

•  Objective1:Determinebeachcharacteristicsthatserveasnestingcues– Beachslopeandwidth– Sandmoisturecontentandgrainsize

•  Objective2:Determinehowalteringkeycharacteristicsthroughbeachrestorationaffectsnesting

1

4

3

2

Objective2:MethodsAlteringbeachcharacteristics

•  Dividedcrawlintoquarters

•  Averageddataforeachquarter

•  Slope,moisturecontent,grainsize

CrawlQuarter

Elevation(m

)Objective2:Results

Alteringbeachcharacteristics

Allfalsecrawls(n=25)

Allnests(n=49)

Objective2:ResultsAlteringbeachcharacteristics

CrawlQuarter

Elevation(m

)

Naturalnests(n=19)

Naturalfalsecrawls(n=7)

FSR:flatnests(n=8)

FSR:flatfalsecrawls(n=4)


CrawldistancesonFSR:flat

CrawlType

Distancefrom

water(m

)

Falsecrawln=4Nestn=8


CrawlQuarter

Elevation(m

)

Naturalnests(n=19)Naturalfalsecrawls(n=7)FSR:flatnests(n=8)FSR:flatfalsecrawls(n=4)

FSR:slopednests(n=5)FSR:slopedfalsecrawls(n=8)

Objective2:MethodsAlteringbeachcharacteristics

•  Referencepoint•  Rateofchange(change/1.5m)

•  Profile,moisturecontent,grainsize


•  Differenceinnestsandfalsecrawls1.5mfromhead

Nests Falsecrawls

Distancefromhead(m) Distancefromhead(m)

Changeperunit(m)

Changeperunit(m)

•  Objective2:Determineifalteringkeycharacteristicsthroughbeachnourishmentaffectstheirroleasnestingcues– Slope– Tooflat/toosloped=morefalsecrawls– Affectsitsabilitytofunctionasaneffectivenestingcue

Objective2:ConclusionAlteringbeachcharacteristics

Summary

•  Biggereffectsizeafterfull‐scalerestoration•  Beachslope/widthandsandmoisturecontent/grainsize=loggerheadnestingcues

•  Alteringbeachslopeaffectsitsabilitytofunctionasanestingcue

Whyisthisimportant?

•  1stdatatoshowtheimportanceofslope•  Laysgroundworkforfurtherresearch•  Experimentwithalternatetemplatedesigns

Acknowledgments

•  Committee:Drs.LlewellynEhrhart,RossHinkle,MarioMota,JohnWeishampel

•  Fieldcrew:MeredithHickman,SarahKrieg,RobynLee,GregNorris

•  Labmates:SimonaCeriani,JenniferElliot,ChrisLong,CherylSanchez,JenniferSolis,AndrewSterner,TerryWilliamson

•  UCFMarineTurtleResearchGroup•  EcologicalAssociates,Inc.,RickHerren,KristenKneifl,MikeMcGarry

•  UCFDepartmentofEngineering

Download - Oral presentation at National Conference on Beach Preservation Technology (2012)

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