Biology and conservation of the Harpy Eagle in Venezuela and Panama

231 Pages·1996·7.8 MB·English

by  Alvarez-Cordero, Eduardo

BIOLOGYANDCONSERVATIONOFTHEHARPYEAGLE
INVENEZUELAANDPANAMA
BY
EDUARDOALVAREZ-CORDERO
ADISSERTATIONPRESENTEDTOTHEGRADUATESCHOOL
OFTHEUNIVERSITYOFFLORIDAINPARTIALFULFILLMENT
OFTHEREQUIREMENTSFORTHEDEGREEOF
DOCTOROFPHILOSOPHY
UNIVERSITYOFFLORIDA
1996
ACKNOWLEDGMENTS
Manyprivateandgovernmentinstitutionsandagreatnumberofindividuals
contributedtotherealizationofthisstudy. However,beforeanyandall,Iwishto
recognizeandthankLucieE.Zaugg,friendandwife,forthecommitmentandloving
supportanddedicationinvestedtoensurethatourfamilysurvivedtheselongyearsas
webecamestudentsagain.Webothknewthatitwouldbeaperiodfullofgrowth,
sacrifices,andtrials.LuciehasdonemorethanhershareeverytimethatIdisappeared
intothejungle(oncefor3months),andhastolerated(barely)havingmyworkofficeat
home.Ourtwosons,JorgeDavid(12)andJuanMichael(9),havegrownwiththe
projectandarewaitingandwonderingifthereisalifeafterthePh.D.
WecametoGainesville,Florida,thankstotheencouragementofPoly,Dr.
EleanorStorrs,whoconvincedDr.KentRedfordtogivemeanaudience.HeandDr.
JohnRobinsonprovidedmewiththeopportunitytobecomea"Gator,"aftera10year
sabbaticalfrombeingan"Aggie,"andIthankthemforit.Atvarioustimesduringthe
difficultadjustmenttouniversitylife,wordprocessors,andeconomicchallenges,their
ProgramforStudiesinTropicalConservation(PSTC)cametotherescue(evenwhen
theyknewthatIwasnotfromMexicoorBrazil).
Dr.MichaelW.Collopyperhapsdidnotdeservetogetstuckwithmeandthis
project,butsuchislife.Heapproachedthischallengewithhisalwayspositiveand
generousattitude.HerewasaLatino,withZEROexperienceworkingwithraptors,
sayingthathewouldtacklethebiggestoneofthemall.Hehasbeenapatientmentor,
answeringmyeveryquestion,carefullyeditingmydocuments,andkindlyrespectingmy
frequentignoranceabouthisfieldofexpertise.Hewasgenuinelycommittedtoseeme
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through,evenafterrealizingthatfundingwouldbeverydifficulttoobtain.Icannot
thankhimenoughfortrustingmetogetthejobdone,andfortheconstant
encouragementduringthemanymonthsittookmetoshapethisdissertation.Theone
thingIknowthatImustdotoshowhimmyrespectistoturnthisdocumentintopeer-
reviewedpublications.
Drs.MelvinE.Sunquist,SusanK.Jacobson,MarianneC.Schmink,andRichard
A.KiltieservedonmycommitteeandwereextremelysupportivewhileIpreparedthis
dissertation.Theyeachprovidedadifferentinsightandcarefuleditingtoimprovethis
document.Iappreciatetheirpatienceandinterestinthisprojectthatpotentiallyhad
many"looseends"andfewguaranteesofbeingattainable.Ienjoyedtheopportunityto
takeclassesfromDr.SchminkandDr.Jacobson;Ilearnedmuchfromthose
experiencesandbothofthesesuper-teachers.
IrecognizethesupportoftheUniversityofFlorida,anditsDepartmentof
WildlifeEcologyandConservationfortheopportunitytotrainandlearnonthiscampus,
fortheequipmentloans,thewonderfullibraries,andflawlessaccesstotheInternetso
thatIcouldtracktheHarpyEaglesfrommyPC.
In1988,1visitedThePeregrineFund(Boise,Idaho)andmetDr.BillBurnham,
Presidentofthatorganization.WediscussedmyplanstoworkwiththeHarpyEagle.
AfterImovedtoFlorida,hestayedintouchandoftenofferedhissupport.In1991,as
soonasIwasreadytogointothefield,itbecameevidentpromisedfundingwasnot
forthcoming posinganadditionalchallengeforthisproject.Througha"gentlemen"
,
agreementbetweenDr.CollopyandDr.Burnham,Iwaspresentedwiththeunique
opportunityofdevelopingthefieldprojectfortheHarpyEagleConservationProgramof
ThePeregrineFund.Theyemployedmeandsupportedalltheneedsoftheproject.
Theyhavetreatedmeasaprofessionalandafriend, whilealsoallowingmethe
latitudeofbeingastudent.Icouldnothavehopedforanythingbetter,butthe
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Burnhamsalsohaveprovidedmyfamilywiththeconstantassurancethatevenifwe
werenotinBoise,webelonged.Thewholeheartedandongoingcommitmentofthe
"PeregrineFundFamily"tosupportthisprojectislargelycreditedforwhatwehave
beenabletoaccomplishsofar.Iextendmygratitudetoallmycolleagues,coworkers,
directors,andthemanymembersthatcontinuetosupportthiswork.
In1989,IbegantrainingayoungVenezuelanwhoclimbedthefirstactiveHarpy
EaglenestthatDr.CollopyandIfoundduringthepreliminaryfieldseason.Eladio
RafaelAlvarezwassponsoredin1992byThePeregrineFundasafull-timeField
Assistanttothisstudy.Hisdedicationandcontributiontoallaspectsofthefieldwork
haveinagreatmeasuremadethisstudypossible.Rafaelistheworldexpertonthis
species,havingseenandhandledmoreeagles,andhavingfoundandclimbedmoreof
theirneststhatanyoneelse;wheneverIwrite"I",pleaseread"RafaelandI".
IwishtomakespecialmentionoftheCenterfortheStudyforTropicalBirds,
Inc.,anditsDirector,JackClinton-Eitniear,whofundedmyfirstfieldtripin1989.Ithank
themforbelievingitcouldbedone!
InPanamaweworkedundera5-yearcooperationagreementestablishedin
1991betweenoursponsoringorganization,ThePeregrineFund,andtheProtected
AreasbranchoftheNaturalResourcesInstitute(InstitutodelosRecursosNaturales
Renovables-INRENARE).Wemadenumerousfriendsinthiscountry,wherewealways
feltathome.IndraS.Candanedowasaconstantcollaboratorandservedasthe
nationalcounterparttoourinvestigation.KarlaAparicioandBelkysJimenezalsogave
ussupport;Karlacollectedvaluableinformationduringherinternshipwiththeproject.
JacoboLacsprovidedmanyimportantinsightsandlogistics,andleadustoanestin
theAtlanticBasin.WealsothankourcollaboratorsinANCONfortheircooperation.Dr.
NathanGaleandhiswifealsodedicatedmanyhourstohelpusanddemonstratedtheir
commitmenttohelptheeagles.Wededicateaspecialmentionofgratitudetothe
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peopleoftheDarien,particularlytheparkrangersheadedby"SrChicho"whoadopted
usandtookuseverywhereinatimelyandsafefashion.
InVenezuelaourresearchprogramwasbackedbyCVG-EDELCAandthe
VenezuelanAudubonSociety(SCAV-SociedadConservacionistaAudubonde
Venezuela),andauthorizedthroughannuallyrenewedResearchPermits(Lisenciade
CacehaCientifica)issuedbyPROFAUNA,theWildlifeProgramsOfficeoftheMinistry
fortheEnvironment(MARNR-PROFAUNA.MinisteriodelAmbienteydelosRecursos
NaturalesRenovables,ServicioAutonomoProgramasdeFauna).Since1988,
EDELCA'sstaffhavesupportedthisinvestigationofHarpyEagles.Thiscompanyhas
providedahousingfacilitytobasetheproject,spaceforalargeflight-pentohold
captiveeagles,technicalandlogisticassistance,andeventheoccasionaluseof
helicopters.
ThemanagementoftheVenezuelangovernment'sregionaldevelopment
corporation(L.Camposinlitt.,November30,1995),CorporationVenezolanade
Guayana(CVG),grantedaccesstoanextensivedatabaseonregionalnatural
resourcesheldbyTECMIN(CVG-TecnicaMinera).Wethankthemforthisprivilege.
WeacknowledgethelogisticsupportreceivedfromCVG-FerromineradelOrinoco,
particularlyfromtheiraviationdepartment.
OurfriendsinGurideserveaspecialmention,fortheirconstantencouragement
andtimelyhelp--inparticularmycoworkersatEcologia.Teo,Martin,Asterio,Leon,AN,
whostilltreatmeasfamily.TheBalbasfamilywasourhotelduringthefirstyear,
providing5startreatmentforallthenumerousgueststhatgotinvolvedwiththisproject.
LuisA.Balbasasbeenaconstantcompanioninthiswork,basicallysolvingany
problems.Iregretthathehasnotbeenabletoseemuchofthewildeagles,buthehas
doneanexcellentjobcaringforthelivebirdswehaverescuedandbroughttoGuri.I
alsoowehimforallthetimehehasspentadministratingtheprojectandproviding
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guidancetoRafael. OrlandoBorromeintroducedmetotheuseofGPSandprovided
criticalsupporttoourfieldsurveyinVenezuela.
Fromthestartofthisstudy,cooperationwithagroupofForestryManagement
UnitswascrucialtotheinvestigationofHarpyEagles.AlongtheImatacaRangewe
workedwithSOMAGUA,CODEFORSA,MaderasNuriaI,INTECMACA,Aserradero
HermanosHernandez,andMADERORCA.IntheSupamoRiverBasinourresearch
wassupportedbyAserraderoMatamoros,AserraderoElManteco,andAserradero
Yocoima.LuisMatamoros,andhiswifeVerenice(mysister),wereamongthefirstto
enlistonourbadwagonandhaveprovidedallsortsofsupport.
TheFuerzasArmadasdeCooperation(FAC),theNationalGuardinVenezuela
deservespecialmentionfortrackingdownthehuntersthatshottwooftheeaglesthat
weweremonitoring,andmoreimportantly,forretrievingNASA'ssatellitetrasmittersso
thatwecouldusethemagain.Misioncumplida!
Numerousprivateranchesallowedustoconductresearchandprovidedlogistic
supportandimportantbackgroundinformationonthenestswithintheirproperties. We
aregratefulforthecooperationandsupportreceivedfromalloftheseentitiesandtheir
representatives.
TocompileandupdatetheexistingrecordsfortheHarpyEagleweworkedin
MexicowithEduardoInigo-EliasandGuidoRhar;inCostaRicawithSusanWilsonand
BelkysJimenez;inColombiawithCesarMarquez;andinEcuadorwithPeterJennyand
MauricioGuerrero.WebeganworkinPeruwithRenzoPiana.FernandoAntonini,
anotherstudentfromthatcountry,embarkedunderourguidanceonapreliminaryfield
surveyoftheTambopataregionin1996.InGuayana,wecollaboratedcloselywithNeil
Rettigwhohadalreadyaccomplishedanimpressivefieldsurveyandproducedfilmson
theHarpyEaglesinthatcountry.SaraGilbertagreedtocollectrecordsforSuriname
duringherstayinthatcountry.SteveMcGehee,arespectedfriendandcolleaguehas
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providedanendlessstreamofpricelessreferencesthatonlyhecanlocate.Mike
McMillianvisitedthefieldprojectinVenezuelatodeliverneededequipmentandprovide
additionaltelemetrytrainingtoRafael.
WeweretrainedtoworkwiththeeaglesbyDr.DavidEllis(NBS,Patuxent,MA),
oneofthepioneeringexpertsinthefieldofsatellitetelemetryappliedtolargeavian
species.Heprovidedvaluableadviseandencouragement,servingastheinvisible
committeememberthateverygradstudentshouldhave.Between1992-96,Dr.Ellis
arrangedthesupplyofARGOS-TIROSsatellitesystemtransmitterstoourproject
throughaworldwideeffortfundedbyNASA;fouradditionaltransmitterswere
purchasedbyThePeregrineFund(1993-95).Dr.PaulHowie,ofMicrowaveTelemetry,
notonlyprovidedthebestsatellitetransmittersavailable,butalsogaveusthebest
personalizedattentionandadvise.Irecognizethelargecontributionof NASAin
supplying10satellitetransmitterstodate,andtheconstantandreliablesupportofthe
peoplethathandletheincomingdata,particularlyCharlieandJon.
Weacknowledgethesupportofthefollowingcompanies:TrimbleNavigation
loanedtopofthelineGPSsurveyingequipmentforthecollectionofdatalayersusedin
ourGeographicalInformationSystem.OursGISwasdevelopusingARCVIEW(verion
2.1byESRI)donatedtoThePeregrineFundbyEnvironmentalSystemsResearch
Institute(Redlands,CA). HortonManufacturingCompany,Inc.,(Tallmadge,Ohio)
donatedacrossbowusedtogetourclimbingropesoverthenesttrees;thisavoided
thedamagedonetotreeswhenclimbingwithspikesandallowedustousesaferrope
climbingmethods.AVINETrecentlydonatedPesolascalestotheproject.
Dr.StefanGorzulaandGlendaMedinadeservecreditforgivingmethefirst
trainingIeverreceivedinFieldBiology.Stefanhasbeenavaluableandsupportive
colleaguesinceImethimintheearly1980s.Glendaintroducedmetotheworldof
birdsandfieldtechniques.Dr.LeeHarperalsocontributedtomyearlytraining.
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Dr.OmarLinaresopenedthedoorsofhislaboratoryattheUniversidadSimon
Bolivartohelpprocessandidentifythepreyremainscollectedfromnests.Oneofhis
studentsassistedinthistask.
NeilRettig,theotherworldexpertonthespecies,hasdemonstratedaLatino
likeheartandwillingnesstoshare.Heprovidedmanyimportantsuppliesandthe
crossbowtoshootlinesthatenabledustoclimbthenests.Healsowaskindenoughto
guidemeintoGuyanaandshowmehisnests.Thesupportofhispartner,KimHayesis
alsorecognized,aswellasthefundsprovidedtotheprojectbyNeilRettigProductions.
WeoweourlivestoLuisEnriqueArnal,Kike,masterfulclimberwhotrainedus
toreachthenests.ALWAYSonrope!SAFETYfirst!IrememberwhenIwasfirstgiven
enoughclimbingropeandnotraining,andtoldtojustdoit!Also,Kikehasbeenthe
project'sphotographersinceImethimonaCuipointheDarienin1993.
Imustmentionagroupoflong-timefriendswhoadoptedthecauseofthe
eaglesandpouredtheirheartsintomakingthisprojectareality.PeterE.Kung,for
gettingmehookedonfieldbiology>20yrago,teachingmetoworkwithbirds,andfor
histotaldedicationtotheproject'ssuccess.HealonedeservescreditfortheGPS
surveys,anenormousaccomplishment,andforbelievingthatwecouldcreateaGISon
ashoestringbudget.ZanMerrillprovidedusefuladviseandunendingsupport
throughoutthestudy,alwayssharingthevision.GustavoA.MartinezG.dedicatedhis
alltotheneedsoftheproject,servingasthein-countryclearinghouseforthe
PeregrineFundduringmanyofourtrips.GusandElba,hiswife,pouredtheirkindness
andhumoronmyriadsofpeopletomakesurethattheysupportedourgoals.Guswas
instrumentalinsecuringtheGISinformationandbasemapsforthestudy.Hearranged
planeandhelicopterrides,providedofficesupport,andevengaveourpresentationat
ascientificmeetingwhenwecouldnotbethere.Milardosdegracias!!Gusalso
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traveledmanytimestoFlorida,spending nightsanddaysmakingmyPCrunflawlessly
sothatIcouldcompletethisportionofthestudy.
MyfamiliesinVenezuelaandCanadawerealwaysbehindmeduringthis
endeavor. InCaracas,myparentsMargotandFelipe,andmysisterBelen,havebeen
aconstanthelpandhaverunmanyerrandstohelpmeaccomplishthiswork.My
motherbasicallydonatedherusedcarfortheuseoftheproject.Her1962FordFalcon
madeinnumerabletripsintotheloggingtrailsintherainforestuntilitwastotaledinan
unfortunateaccident.MybrotherCesarAlvarezhasbeenextemelysupportive, and
alsoarrangedimportantlogisticcooperationfromCVGaffiliatedcompaniesinthe
GuayanaRegion.RuthandFerriesinAlbertaalsosupportedthisaccomplishmentin
everywaypossible.
Finally,IacknowledgethewonderfuleffortsofM.J.Schaerinformattingand
pullingtogetherthedraftsandfinalversionofthisdissertation,alwayswithapositive,
friendly,andprofessionalattitude.
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TABLEOFCONTENTS
page
ACKNOWLEDGMENTS »
LISTOFTABLES xiii
LISTOFFIGURES xiv
ABSTRACT xvi
CHAPTERS 1
1 GENERALINTRODUCTION 1
Introduction 1
Background 2
WhyStudytheHarpyEagle? 3
RelatedResearch 6
FactVersusFolkloricNotions 8
InstitutionalSetting 9
OrganizationoftheDissertation 11
LimitationsofthisStudy 13
2 GEOGRAPHICANDECOLOGICALRANGEOFTHEHARPYEAGLE 14
Introduction 14
TheImportanceofHistoricalandRecentRecords 16
TheLandscapeApproachtoHabitatEvaluation 17
Methods 21
ProjectAreasandSiteSelection 21
SourcesandSearchforRecords 24
FieldSurveysinVenezuelaandPanama 27
HabitatEvaluation 30
ExplorationsinOtherCountries 31
Results 31
HistoricalandRecentRecordsinVenezuela 31
NestSurveyinVenezuela 36
HistoricalRecordsinPanama 39
NestSurveyinPanama 41
RecordsfromOtherCountries 42
Discussion 47
x