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IRCFREPTILES&HIBIANS•20(1):20–22•MAR2013
Here I document copulation of Cottonmouths(Agkistrodon piscivorus)observedatapproximately1630hon27August2012inasmallinletofBlueCreek,CovingtonCounty,Alabama(31.14449N,86.67554W).Thepairwasdiscoveredwhileconductingsurveysofthesurroundingseep-agehabitat. Thesnakeswerediscoveredincopula(hemipeneintro-missionwasconfirmed),facingoppositedirections(Fig.1).Theyremainedmotionlessinthispositionfor15minuntil,inanattempttoobtainacloservantagepoint,Idisturbedthem.Onmyapproach,thefemalebecameagitatedandpro-ceededtodragthemaleawayfrommyposition.Atfirst,sheattemptedtodragherpartnertohigherground,butbeingsig-nificantlysmaller,theattemptwasunsuccessful.Afterseveralminutes,whilethemaleremainedpassive,thefemaledraggedthemaleroughly2mthroughthewaterandontotheoppo-sitebank(Fig.2).Thefemalethenclimbedontopofthemale,whilebothsnakeswerestillpartlysubmerged(Fig.3).
Currentinformationregardingthetimingofmatinginwildsnakesisalmostwhollyreliantontheanecdotal
evidenceofchanceencounters(AldridgeandDuvall2002).Also,implicitcorrelatesofmating,suchasmale-malecom-bat,oftenareusedtodeterminematingseasonsofviperids,largelybecauseencounterswithcopulatingpairsoccursoinfrequently(Wharton1966,Grahametal.2008,Siegeletal.2009).Recently,analysesusinghormonalandhistologi-calcorrelatesofreproductivecycleshavebeenemployedinattemptstoestimatematingperiods(Grahametal.2008).However,asGrahametal.(2008)noted,thesefactorscanbeinconsistentacrosssnakespeciesand,hence,directevidencefromwitnessedcopulationeventsremainsavaluablefoun-dationfromwhichtodrawreliableconclusionsaboutmat-ingseasons.Therefore,additionalreportsofmatingeventsinsnakes,includingthosespeciesforwhichinformationisalreadyavailable,willenhanceourunderstandingofmatinginthosespecies.
A Chance Encounter with Copulating Cottonmouths (Agkistrodon piscivorus)
GeorgeC.Brooks
DepartmentofAnimalandPlantSciences,UniversityofSheffield,SouthYorkshire,S102TN,UK([email protected])
Photographsbytheauthor.
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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
moditia erere nonsedis ma sectia-tur ma derrovitae voluptam, as
IRC
F
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
Copyright©2013.GeorgeC.Brooks.Allrightsreserved.
WWW.IRCF.ORG/REPTILESANDAMPHIBIANSJOURNAL
Fig. 1.TheoriginalpositionoftwocopulatingCottonmouths(Agkistrodon piscivorus)inCovingtonCounty,Alabamaon27August2012atapproxi-mately1630h.
Fig. 2.Thefemaleattemptstodragthemaleoutofthewaterontheoppositebank.
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IRCFREPTILES&HIBIANS•20(1):20–22•MAR2013
Duringthisentireperiod,thepairremainedlockedviathemale’shemipene(Fig4). Thefemalewasidentifiedbyitssmallsizeincomparisontoitspartnerandclosescrutinyofthepositionofthemale’shemipene.Male-biasedsexualsize-dimorphismhaspreviouslybeendocumentedinA. piscivorus(HillandBeaupre2008).Inaddition,thefemalewasintheprocessofecdysis(Fig5).Thepresenceofsloughononeindividualisconsistentwithpreviousobservationsofpitvipers;femalessheddingpriortomatingmightindicateafunctionallinkbetweenthesetwoprocesses(Kubieetal.1978,Ashton2003). Interestingly,Fitch(1975)notedasimilarcopulationencounterinDiadophis punctatus,inwhichonlythefemalebecameagitatedwhendisturbed,resortingtodragginghermalepartnerinanattempttoescape.Fitch(1975)offerednoexplanation for thisbehavioralpeculiarity,andtomyknowledge,nootherstudyhasmentionedsimilarpassive-nessincopulatingmalesnakes.Unfortunately,thepaucityofinformationregardingreproductiveandbehavioralecologyinsnakespreventsanassessmentofwhethertheseobservationsrepresentanythingmorethancoincidence. Clearlymoreworkisneededtoobtainabetterunder-standingofmatingbehavior in snakes,beginningwithamorepreciseestimateofwhenmatingoccurs.Histologicalandobservational evidenceprovidedbySiegel andSever(2007)suggestedthatA. piscivorusdisplaysbiennialbreeding,withmatingseasonsinthespringaswellasinlatesummer/earlyautumn.ThisobservationjoinsseveralothersthathavereportedmatingA. piscivorusinlatesummer/earlyautumn(summarizedinGrahametal.2008),whichcorrespondswiththepeakoftestosteroneproduction,aswellasspermatogen-esisandtheenlargementoftherenalsexsegment (Johnsonetal.1982,Zaidanetal.2003,Grahametal.2008).
AcknowledgementsFundingforthisresearchwasprovidedbyIOS-1051367toT.Langkilde.SpecialthanksgotoSeanGrahamforhisconstructivecommentsonanearlierdraftthatgreatlyimprovedthemanuscript.
Literature CitedAldridge,R.D.andD.Duvall.2002.Theevolutionofthematingseasoninthe
pitvipersofNorthAmerica.Herpetological Monographs16:1–25.
Ashton,K.G.2003.MovementsandmatingbehaviorofadultmaleMidgetFadedRattlesnakes,Crotalus oreganus concolor,inWyoming.Copeia2003:190–194.
Fitch,H.S.1975.AdemographicstudyoftheRingneckSnake(Diadophis puncta-tus)inKansas.University of Kansas Museum of Natural History Miscellaneous Publications62:1–53.
Graham,S.P.,R.L.Earley,S.K.Hoss,G.W.Schuett,andM.S.Grober.2008.ThereproductivebiologyofmaleCottonmouths(Agkistrodon piscivorus):Doplasmasteroidhormonespredictthematingseason?General and Comparative Endocrinology159:226–235.
Hill,J.andS.Beaupre.2008.Bodysize,growth,andreproductioninapopulationofWesternCottonmouths(Agkistrodon piscivorus leucostoma)intheOzarkMountainsofnorthwestArkansas.Copeia2008:105–114.
Johnson,L.F.,J.S.Jacob,andP.Torrance.1982.AnnualtesticularandandrogeniccyclesoftheCottonmouth(Agkistrodon piscivorus)inAlabama.Herpetologica38:16–25.
BROOKS
Fig. 3.Thefemaleclimbsontopofthemalewhilebothsnakesarestillpartlysubmerged.
Fig. 4.Themalehemipene;thetwosnakesremainedlockedforthedura-tionoftheobservation(~40min).
Fig. 5.Remnantsofecdysisarestillvisiblenearthetailofthefemaleobscuringthehemipene.
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BROOKS IRCFREPTILES&HIBIANS•20(1):20–22•MAR2013
Kubie,J.L.,J.Cohen,andM.Halpern.1978.Sheddingenhancesthesexualattrac-tivenessofoestradioltreatedgartersnakesandtheiruntreatedpenmates.Animal Behaviour26:562–570.
Schuett,G.W.1992.Islong-termspermstorageanimportantcomponentofthereproductivebiologyoftemperatepitvipers?,pp.169–184.In:J.A.CampbellandE.D.Brodie(eds.),Biology of the Pitvipers.Selva,Tyler,Texas.
Siegel,D.S.andD.M.Sever.2007.Spermaggregations infemaleAgkistrodon piscivorus(Reptilia:Squamata):Ahistologicalandultrastructuralinvestiga-tion.Journal of Morphology269:189–206.
Siegel,D.S.,D.M.Sever,J.L.Rheubert,andK.M.Gribbins.2009.ReproductivebiologyofAgkistrodon piscivorusLacépède(Squamata,Serpentes,Viperidae,Crotalinae).Herpetological Monographs23:74–107.
Wharton,C.H.1966.ReproductionandgrowthintheCottonmouth,Agkistrodon piscivorusLacépède,ofCedarKeys,Florida.Copeia1966:149–161.
Zaidan,F.,III,D.L.Kreider,andS.J.Beaupre.2003.Testosteronecyclesandrepro-ductiveenergetics:ImplicationsfornorthernrangelimitsoftheCottonmouth(Agkistrodon piscivorus leucostoma).Copeia2003:231–240.