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IRCFREPTILES&AMPHIBIANS•19(1):64–66•MARCH2012

I N T R O D U C E D S P E C I E S

IRCF REPTILES & AMPHIBIANS • VOL15, NO 4 • DEC 2008 189TABLE OF CONTENTS

T A B L E O F C O N T E N T S

F E A T U R E A R T I C L E S

Chasing Bullsnakes (Pituophis catenifer sayi) in Wisconsin: On the Road to Understanding the Ecology and Conservation of the Midwest’s Giant Serpent ...................... Joshua M. Kapfer 190

The Shared History of Treeboas (Corallus grenadensis) and Humans on Grenada: A Hypothetical Excursion ............................................................................................................................Robert W. Henderson 198

R E S E A R C H A R T I C L E S

The Texas Horned Lizard in Central and Western Texas ....................... Emily Henry, Jason Brewer, Krista Mougey, and Gad Perry 204 The Knight Anole (Anolis equestris) in Florida

.............................................Brian J. Camposano, Kenneth L. Krysko, Kevin M. Enge, Ellen M. Donlan, and Michael Granatosky 212

C O N S E R V A T I O N A L E R T

World’s Mammals in Crisis ............................................................................................................................................................. 220 More Than Mammals ...................................................................................................................................................................... 223 The “Dow Jones Index” of Biodiversity ........................................................................................................................................... 225

H U S B A N D R Y

Captive Care of the Central Netted Dragon ....................................................................................................... Shannon Plummer 226

P R O F I L E

Kraig Adler: A Lifetime Promoting Herpetology ................................................................................................ Michael L. Treglia 234

C O M M E N T A R Y

The Turtles Have Been Watching Me ........................................................................................................................ Eric Gangloff 238

B O O K R E V I E W

Threatened Amphibians of the World edited by S.N. Stuart, M. Hoffmann, J.S. Chanson, N.A. Cox, R. Berridge, P. Ramani, and B.E. Young .............................................................................................................. Robert Powell 243

CONSERVATION RESEARCH REPORTS: Summaries of Published Conservation Research Reports ................................. 245 NATURAL HISTORY RESEARCH REPORTS: Summaries of Published Reports on Natural History ................................. 247 NEWBRIEFS ...................................................................................................................................................................................... 248 EDITORIAL INFORMATION ..................................................................................................................................................... 251 FOCUS ON CONSERVATION: A Project You Can Support ............................................................................................... 252

Front Cover. Shannon Plummer.Totat et velleseque audant mo estibus inveliquo velique rerchil erspienimus, quos accullabo. Ilibus aut dolor apicto invere pe dolum fugiatis maionsequat eumque moditia erere nonsedis ma sectiatur ma derrovitae voluptam, as quos accullabo.

Back Cover. Michael KernTotat et velleseque audant mo

estibus inveliquo velique rerchil erspienimus, quos accullabo. Ilibus

aut dolor apicto invere pe dolum fugiatis maionsequat eumque

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IRC

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REPTILES & AMPHIBIANSC O N S E R V AT I O N A N D N AT U R A L H I S T O R Y

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BurmesePythons(Python molurus bivittatus orP. bivitta-tus)havebeenreportedtoconsume25speciesofadult

birdsinEvergladesNationalPark,Florida(Doveetal.2011),butuntilnownorecordsdocumentedthisspecieseatingbirdeggs.Herewereportthreerecentcasesofbird-eggconsump-tionbyBurmesePythonsanddiscussegg-eating inbasalsnakes. On8January2011,anadult(2.78msnout-ventlength[SVL],3.14mtotallength[TL],13.9kg)femaleBurmesePythonwascapturedonacanalbank(L-29)adjacenttoU.S.Highway41,nearEvergladesNationalPark,Miami-DadeCounty,Florida(25.76200°N,80.78211°W;WGS84).ThelowerGItractincludedasmallamountofdecomposedfeath-ers,smallheavilydigestedbones,andthecrushed,butintact,remainsoftwobirdeggs.Theseeggremainsweredeposited(EVER44949)intheSouthFloridaCollectionsManagementCenter,EvergladesNationalPark,Homestead,Florida.Manysmallpiecesofeggshellfragmentswereattachedtothewhiteeggmembranes(Fig.1)makingspeciesidentificationpos-sible.WeusedtechniquesdescribedinDoveetal.(2008)toobtainDNAsequencesforcytochromecoxidasesubunit1(CO1)fromtheintacteggmembranes.DNAsequenceswerecomparedtotheBarcodeofLifeDatabase(www.boldsystems.org/views/login.php)toobtain100%matchestoLimpkin(Aramus guarauna).Thecoloroftheeggshellfragmentscon-sistedofgrayishwhitegroundcolorwithfaintpinkish-brown,buffsplotchesontheoutside,andtheinnershellwaswhite(notblueasinotherbirdspecies),whichiscongruentwithanaccountforthisspecies(Bryan2002).FollowingDNAiden-tification,theeggshellfragmentswerecomparedtoreferencespecimensofLimpkineggsattheSmithsonianInstitutionforverification.Pigmentationoftheeggshellsisevidencethattheeggswerelaidandnotpartofaconsumedadultbird.Pigmentationissecretedintheuterusofmostbirdsjustpriortolayingandisthefinalstepineggproduction(Proctorand

Lynch1993).WedidnotfindassociatedwiththissampleanyevidenceofembryosorblackdownyfeatherstypicalofLimpkinchicks. On themorningof21May2011, theMiami-DadeFireRescueVenomResponseUnitrespondedtoaruralresi-denceinsouthwesternMiami-DadeCounty(25.54646°N,80.54573°W;WGS84)followingareportthatapythonwasseennearthenestofafree-rangingGuineafowl(Numida

Consumption of Bird Eggs by Invasive Burmese Pythons in Florida

CarlaJ.Dove1,RobertN.Reed2,andRayW.Snow3

1SmithsonianInstitution,DivisionofBirds,NHBE-600,MRC116,Washington,DistrictofColumbia20560,USA([email protected])2U.S.GeologicalSurvey,FortCollinsScienceCenter,2150CentreAve,BldgC,FortCollins,Colorado80526,USA([email protected])

3NationalParkService,EvergladesNationalPark,40001StateRoad9336,Homestead,Florida33034,USA([email protected])

Fig. 1.TwoLimpkin(Aramus guarauna)crushedbutintacteggs(top;EVER44949)recoveredfromaBurmesePythondigestivetractandcom-paredtoareferenceLimpkinspecimen(below;USNM25786)forsizeandcolorpatterns.Thearrowshowsfragmentsofeggshellsfromthepythonsampleplacedonthemuseumspecimenforcolorcomparison.PhotographbyDonHurlbert,SmithsonianInstitution.

http://www.ircf.org/journal/

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meleagris domesticus)with10eggsthathadrecentlydisap-peared.TheVenomUnitcapturedanadult(2.27mSVL,2.61mTL,6.73kg)maleBurmesePythonattheresidenceat11:00AMthesameday.Duringtransport,thesnakeregur-gitatedaGuineafowlhen(928g)and10intacteggs(fiveofthesearedepictedinFig.2).ThelandownerclaimedthatthiswasthesecondtimeshehadnotedthedisappearanceofaGuineafowlanditseggs,butshehadnotpreviouslyobservedasnake.Thepythonisnowcatalogued(USNM558849)intheherpetologicalcollectionsattheSmithsonianInstitution.TheregurgitatedGuineafowleggsmeasured45.6–49.0x35.3–37.8mmandweighed30–36g,suchthateacheggrepresentedapproximately0.5%ofthepython’sbodymass.Limpkineggsaverage55–64x41–47mm(Walters1994).Theserepresentexceptionallysmallindividualpreyitemsforsnakesofthissize. Inadditiontothetwoexamplesdescribedabove,birdeggfragmentswerefoundintheintestineofathirdBurmesePythonfromU.S.Highway41nearEvergladesNationalPark,butevidencewasinsufficienttoidentifythespeciesofbird. Durophagy(consumptionofhard-shelledobjects)isrela-tivelyuncommonamongsnakes(Savitsky1983).Specializedegg-eaters(e.g.,Dasypeltis)exhibitasuiteofmorphologicalandbehavioraltraitsallowingthemtoingesteggsthatareverylargeinrelationtothesizeofthesnake’shead(Gans1952,GartnerandGreene2008),butfewsnakesaresohighlyspe-cialized.CundallandGreene(2000:326)statedthatonlytheColubroideahavemorphologicalspecializationsforhandling

preyitemsthataredifficulttohandle(suchasverylargeeggs),andthatsuchprey“arecorrespondinglyrareorabsentfromthedietsofmorebasalsnakes.”Manycolubroidsnakesthatocca-sionallyconsumerelatively(tothesnake’shead)largebirdeggsexhibitpointedorbladelikehypapophyses(ventralprocesses)onanteriorvertebraethatservetobreaktheeggshellintheesophagus(Mullin1996),andthepresenceofhypapophyseshasbeendescribedasa“criticallimitingfactor”inconsumptionoflargebirdeggsbysnakes(CundallandGreene2000:320). BurmesePythonsexhibithypopophysesoncervicalverte-brae(Fig.3),buttheselackthesharpprojectionsorbladelikeventralsurfaces(cf.ratsnakes;Mullin1996)usuallyassociatedwithspecialistegg-eaters.Thehypapophysesareprominentinanteriorvertebrae(toapproximatelyvertebrum#48,atabouttheleveloftheheart),afterwhichtheyundergorapidreductioninsize.Theyendassmallventralridgesonvertebralcentrabyapproximatelyvertebrum#58,wellbeforethestomach(per-sonalobservation,basedonvertebraefromamaleTL265cmandSVL232.5cm[EVER66690]capturedintheEverglades).TheGuineafowleggsconsumedbythepythonwereentireatthetimeofregurgitation,suggestingthateitherthehypa-pophysesarenotusedtocrusheggsorthattheseeggsweretoosmalltobeengagedbythehypapophyses.Giventheabilityofpythonstodigestevenlargebones,wedoubtthataninabilitytophysicallybreakaneggshellduringingestionwouldimpedeapython’sabilitytoaccesstheegg’scontentsduringdigestion. Our observations of egg eating in Burmese Pythonsarenotuniqueamonglarge-bodiedbasalsnakes,asYellow

Fig. 2.FiveoftenentireGuineafowl(Numida meleagris domesticus)eggsregurgitatedbyaBurmesePython.PhotographbyR.W.Snow,EvergladesNationalPark.

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Anacondas(Eunectes notaeus)inSouthAmericaconsumebirdeggs(StrüssmannandSazima1991;T.Waller,pers.comm.,June2011).Interestingly,weareunawareofanyreportsofconsumptionofavianeggsamongGreenAnacondas(E. muri-nus),BoaConstrictors(Boa constrictor),ReticulatedPythons(Broghammerus reticulatus),orthelargeAfricanpythons(P. natalensisandP. sebae;ReedandRodda2009;T.Waller,J.Rivas,R.W.Henderson,pers.comms.,June2011). SeveralspeciesofcolubroidsnakesnativetoFloridaareknowntoconsumebirdeggs(ErnstandErnst2003).OurobservationsconfirmthatinvasiveBurmesePythonsconsumenotonlyadultbirdsbutalsoeggs,suggestingapreviouslyunrecognizedriskfromthisintroducedpredatortonestingbirds.Howfrequentlysuchpredationmightoccurorwhetheritrepresentsaconsiderableincreaseinthebaselinerateofpredationonbirdeggsbynativesnakesisdifficulttoassess,althoughpythonswouldbecapableofeatingeggstoolargeforconsumptionbymostnativesnakes.Overall,theimpactsofinvasivepythonpredationonnativebirdpreypopulationsremainpoorlyunderstood.

AcknowledgmentsThisworkwas fundedbyEvergladesNationalPark.WethankA.Flanagan,J.Ketterlin,J.Fobb,E.Santiago,andM.Rochfordforassistanceinthefieldandlab.F.Dahlan(SmithsonianInstitution,FeatherIdentificationLab)pro-cessedDNAsamples.C.Ernst,H.W.Greene,C.Milensky,andG.H.Roddaprovidedcommentsonpreviousversionsofthemanuscript.AllresearchmetanimalcareguidelinesofEvergladesNationalPark.Anyuseoftrade,product,orfirmnamesisfordescriptivepurposesonlyanddoesnotimplyendorsementbytheU.S.Government.PhotographswereprovidedbyDonHurlbert(SmithsonianInstitution)andR.W.Snow(EvergladesNationalPark).

Literature CitedBryan,D.C.2002.Limpkin(Aramus guarauna),No.627.In:A.PooleandF.Gill

(eds.),The Birds of North America Online.TheBirdsofNorthAmerica,Inc.,Philadelphia,Pennsylvania.

Cundall, D. and H.W. Greene 2000. Feeding in snakes, pp. 293–33 In: K.Schwenk(ed.),Feeding.AcademicPress,SanDiego,California.

Dove,C.J.,N.C.Rotzel,M.Heacker,andL.Weigt.2008.UsingDNAbarcodesto identifybirds involved inbirdstrikes.Journal of Wildlife Management72:1231–1236.

Dove,C.J.,R.W.Snow,M.R.Rochford,andF.J.Mazzotti.2011.Birdsconsumedby the invasiveBurmesePythonPython molurus bivittatus inEvergladesNationalPark,Florida,USA.Wilson Journal of Ornithology123:126–131.

Ernst C.H. and E.M. Ernst. 2003. Snakes of the United States and Canada.SmithsonianBooks,Washington,D.C.

Gans,C.1952.Thefunctionalmorphologyoftheegg-eatingadaptationsofthesnakegenusDasypeltis.Zoologica37:209–244.

Gartner,G.E.A.andH.W.Greene 2008.AdaptationintheAfricanEgg-eatingSnake:Acomparativeapproachtoaclassicstudyinevolutionaryfunctionalmorphology.Journal of Zoology (London)275:368–374.

Mullin,S.J.1996.AdaptationsfacilitatingfacultativeoophagyintheGrayRatSnake,Elaphe obsoleta spiloides.Amphibia-Reptilia17:387–394.

Proctor,N.S.andP.J.Lynch.1993.Manual of Ornithology.YaleUniversityPress,Princeton,NewJersey.

Reed, R.N. and G.H. Rodda2009.Giant constrictors: Biological and Management Profiles and an Establishment Risk Assessment for Nine Large Species of Pythons, Anacondas, and the Boa Constrictor.U.S.GeologicalSurveyOpenFileReport2009-1202,FortCollins,Colorado.

Savitzky,A.H.1983.Coadapted character complexes in snakes: Fossoriality,piscivory,anddurophagy.American Zoologist23:397–409.

Strüssmann,C.andI.Sazima.1991.PredationonavianeggsbytheboidsnakeEunectes notaeus.Herpetological Review22:118–120.

Walters, M.1994.Birds’ Eggs.DoringKindersley,NewYork,NewYork.

Fig. 3.AnteriorvertebraefromaBurmesePython(Python molurus bivit-tatus orP. bivittatus)(267cmSVL;EVER66690),showinghypapophy-sesbelowthecentrumofeachvertebrum.PhotographbyR.W.Snow,EvergladesNationalPark.