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IRCF REPTILES & AMPHIBIANS • 21(2):73–79 • JUN 2014 73 IRCF REPTILES & AMPHIBIANS CONSERVATION AND NATURAL HISTORY Copyright © 2014. Hayden D. Hedman. All rights reserved. WWW.IRCF.ORG/REPTILESANDAMPHIBIANSJOURNAL T he Gobabeb Research and Training Centre (Fig. 1) is an internationally recognized research station and pre- miere site for training and research in arid-land biology. The station is located in the Namib Naukluft National Park (23°33’42.61”S, 15°2’30.15”E) in Namibia. The research center is approximately 100 km southeast of Walvis Bay (the nearest small town) and 60 km from the Atlantic Ocean (Schulze 1969). The Namib Desert is an expansive land- scape (2,000 x 200 km) with Gobabeb situated at the center of three habitats: Dune, gravel plains, and the Kuiseb River corridor. The region’s monthly average temperature range is 26−32 ºC and daily temperatures sometimes vary by over 10 ºC between day and night. Southern Africa exhibits one of the highest concentrations of endemic species in the world, with more than 80% endemism for some groups of organ- isms (Goldblatt and Manning 2002), and an estimated 92% of the more than 300 species of lizards in southern Africa are indigenous (Branch 1999). Among African nations, Namibia ranks second in lizard diversity (125 species), trailing only South Africa (Bauer 1999). At Gobabeb, faunal and floral surveys have been conducted for the last 50 years, providing an extensive database of its rich biodiversity, with 199 known species of plants, 44 mammals (Fig. 2), 195 birds, and 43 reptiles (Henschel et al. 2006). Gobabeb was founded in 1962 (www.gobabebtrc.org) by the Southern African Museums Association. Since 1998, the Ministry of Environment and Tourism and the Desert Research Foundation Namibia have jointly managed the sta- tion. The station supports a vast array of fields of inquiry, ranging from climate and ecology to geomorphology, con- servation and restoration, and anthropology and archeology. Gobabeb’s visitors include researchers, university groups, Reptiles of the Gobabeb Research and Training Centre Hayden D. Hedman 1 , Helina M. Alvarez 2 , Gustaf P.Kalifeni Hanghome 3 , Maria Eifler 4 , and Douglas Eifler 4 1 School of Natural Resources and Environment, Ann Arbor, Michigan 48109, USA 2 United States Fish and Wildlife Service, Sand Lake National Wildlife Refuge, Columbia, South Dakota 57433, USA 3 Department of Natural Conservation, Polytechnic of Namibia, Windhoek 9000, Namibia 4 Erell Institute, Lawrence, Kansas 66047, USA Photographs by Maria Eifler. Fig. 1. Gobabeb Research and Training Centre provides tier one resources, as evidenced from hosting over 80 Ph.D. and M.Sc. projects as partnerships both from within Namibia and worldwide. Gobabeb has a helpful staff, including two full-time research technicians and interns available to assist with data collection. Research facilities consist of laboratory space and equipment, rentable storage for long-term use, private and semi-private office space, and an arid ecology library with over 1,800 books, journals, and digitally archived items.
Transcript of Reptiles of Gobabeb Research and Training Centre
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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
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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
Copyright©2014.HaydenD.Hedman.Allrightsreserved.
WWW.IRCF.ORG/REPTILESANDAMPHIBIANSJOURNAL
TheGobabebResearchandTrainingCentre(Fig.1)isaninternationallyrecognizedresearchstationandpre-
miere site for trainingand research inarid-landbiology.ThestationislocatedintheNamibNaukluftNationalPark(23°33’42.61”S,15°2’30.15”E)inNamibia.Theresearchcenter is approximately100kmsoutheastofWalvisBay(thenearestsmalltown)and60kmfromtheAtlanticOcean(Schulze1969).TheNamibDesert isanexpansive land-scape(2,000x200km)withGobabebsituatedatthecenterofthreehabitats:Dune,gravelplains,andtheKuisebRivercorridor.Theregion’smonthlyaveragetemperaturerangeis26−32ºCanddailytemperaturessometimesvarybyover10ºCbetweendayandnight.SouthernAfricaexhibitsoneofthehighestconcentrationsofendemicspeciesintheworld,withmorethan80%endemismforsomegroupsoforgan-isms(GoldblattandManning2002),andanestimated92%
ofthemorethan300speciesoflizardsinsouthernAfricaareindigenous(Branch1999).AmongAfricannations,Namibiarankssecondinlizarddiversity(125species),trailingonlySouthAfrica(Bauer1999).AtGobabeb,faunalandfloralsurveyshavebeenconductedforthelast50years,providinganextensivedatabaseofitsrichbiodiversity,with199knownspeciesofplants,44mammals(Fig.2),195birds,and43reptiles(Henscheletal.2006). Gobabebwasfoundedin1962(www.gobabebtrc.org)bytheSouthernAfricanMuseumsAssociation.Since1998,theMinistryofEnvironmentandTourismandtheDesertResearchFoundationNamibiahavejointlymanagedthesta-tion.Thestationsupportsavastarrayoffieldsofinquiry,rangingfromclimateandecologytogeomorphology,con-servationandrestoration,andanthropologyandarcheology.Gobabeb’svisitors includeresearchers,universitygroups,
Reptiles of the Gobabeb Research and Training Centre
HaydenD.Hedman1, HelinaM.Alvarez2,GustafP.KalifeniHanghome3,MariaEifler4,andDouglasEifler4
1SchoolofNaturalResourcesandEnvironment,AnnArbor,Michigan48109,USA2UnitedStatesFishandWildlifeService,SandLakeNationalWildlifeRefuge,Columbia,SouthDakota57433,USA
3DepartmentofNaturalConservation,PolytechnicofNamibia,Windhoek9000,Namibia4ErellInstitute,Lawrence,Kansas66047,USA
PhotographsbyMariaEifler.
Fig. 1.GobabebResearchandTrainingCentreprovidestieroneresources,asevidencedfromhostingover80Ph.D.andM.Sc.projectsaspartnershipsbothfromwithinNamibiaandworldwide.Gobabebhasahelpfulstaff,includingtwofull-timeresearchtechniciansandinternsavailabletoassistwithdatacollection.Researchfacilitiesconsistoflaboratoryspaceandequipment,rentablestorageforlong-termuse,privateandsemi-privateofficespace,andanaridecologylibrarywithover1,800books,journals,anddigitallyarchiveditems.
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localschoolgroups,students,interns,andtourists,aswellasfilmcrews,journalists,andartists.Overall,Gobabebstrivestopromotepublicawarenessandknowledgeaboutdry-landecologyandenvironmentalissues. Our personal investigation was conducted throughErell Institute’s International Research Experience forUndergraduatesthatpairedNativeAmericanundergraduateswithuniversitystudentsfromNamibiaandBotswanainanintensive,hands-onfieldresearchexperiencefocusedonthebehavioralecologyofNamibDesertlizards.
Living Sustainably in a Fragile LandscapeWater is a precious commodity in desert environments;gettingenoughwaterisarealchallengefororganismsthatinhabittheNamibDesert,andthearrayofadaptationsseenthereisimpressive.Althoughvegetationisscarce,ararebutlocallycommonplantisWelwitschia mirabilis,whichgetsmostofitswaterfromtheregion’scharacteristicdewandfogbydirectlyabsorbingmoisturethroughthedenselypackedstomataonitsleaves(Middleton2009).Tenebrionidbeetles,asamechanismtoretainfluidsandreducetheneedtoobtainadditionalwaterformetabolicfunctioning,exhibitthelowesttranspirationratesofarthropodsintheregion(Edney1971). TheGobabebResearchCentreitselfiswelldesignedtoconservewater,notunlikethemanyendemicbeetleswiththeirrigidcarapacesandotherorganismsoftheregionthathaveevolvedadaptationsforlivinginhyperaridconditions.Minimizingwaterlossthoughwasteremovalrequiresintricatephysiologicaladaptationsbymosttaxonomicgroups,whichisanalogoustoGobabeb’sneedtomechanicallydecreaseexcessivewaterloss,accomplishedthroughwater-conservingtoiletsand
showers.Gobabebstrivestoprovideasustainableresearchenvi-ronment.Forbothefficiencyandawareness,Gobabebcloselymonitorsitstotalmonthlyresourceuse,includingelectricity,gas,andwater(www.gobabebtrc.org).Thedozensofsolarpan-elserectedonthestationoffice,researchcabins,andeveninopenterrain(Fig.3)harness100%ofthestation’selectricity.Intotal,thestationhas72lead-acidbatteriesthatarechargedthroughoutthedayandprovideelectricityduringtheevening.
Community at the StationTheGobabebResearchCentrecommunityconsistsof18professionals fromaround theworld.Themultinationalteam strives to accommodate researchers, school groups,professionalconferences,andvisitorsfromallbackgrounds.Thecommunitymembersholdpositions(i.e.,administra-tive,research,training,housekeeping,andmaintenance)toensurethatresearchandeducationcanproceedwhilestayingandstudyingatthecenter.ThemajorityofthehousekeepingandmaintenancestaffconsistsofindigenousAfricansfromtheadjacentTopnaarvillage.Thecenterprovidesservicesforresearchprojectsbutalsoconductsindependentprojectsandhostsconferencestopromoteknowledgeofthediversewild-lifeandhabitatsoftheNamibDesert.
The Gravel PlainsLessthan30mfromtheGobabebentrancegate,thegravelplainsextendforhundredsofkilometersandconsistofrocksub-stratesinvaryingdimensionsandtextures(WhartonandSeely1982).Fromadistance,thelandscapemayseemhomogeneous,butthevarietyofschists,granites,andmarblesformedfromthePrecambrianthroughthePaleozoicEras(Viles2005)sup-portshighreptilediversity,aswellasavarietyofotherAfricanfauna.Thetwo-hourdrivefromWalvisBaytoGobabebalmostalwaysincludessightingsofSpringbok(Antidorcas marsupialis)herds,Ostrich(Struthio camelus),andtheinquisitivestaresofBat-earedFoxes(Otocyon megalotis)ortheoccasionalglowing
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Fig. 2.NocturnallyactiveElephantShrews(Macroscelididae)canbeobservedthroughouttherockoutcropssurroundingthestation.Thesesmallmammalsarewelladaptedtotheextremeheatofthedesertterrain.
Fig. 3.Inaresource-limitedenvironment,sustainableenergyisgeneratedbysolarpanels.
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eyesofaBlack-backedJackal(Canis mesomelas)foragingduringtheevening.RareencountersincludeGemsbok(Oryx gazella),Hartman’sMountainZebra(Equus zebra hartmannae),ortheoccasionalAardvark(Orycteropus afer).
Serpents of GobabebSnakesof theNamibDesertarewelladapted forglidingacrossdunesorcompactlyfittingintosmallrockcrevices.Fortunately, no deadly venomous snakes occur near thestation.Theonlymildlyvenomoussnakesareadders;theHornedAdder(Bitis caudalis;Fig.4)maybeencounteredthroughoutthegravelplains,whereastheSouthernNamibSandAdder(Bitis peringueyi)maybeseenglidingonthedunes.Nohumanfatalitiesareyetrecordedfromtheirbites.Bothmedium-sizedsnakesspendmostoftheirdiurnalactiv-ityhiddenincrevicesorundershrubs,waitingtoambushpreysuchasrodentsorlizards(Branch1999).TheHornedAdder iscommonlyseeninitsdarkredcolormorph,butoccasionalindividualsarelighterred.Inaddition,severalspeciesofsmallto large-bodiedSandandGrassSnakes (Psammophis sp.)occurnearthestation.Thesecomprisealargegenusof23speciesfoundthroughoutAfrica(Branch1999).SandSnakesareveryfast-moving,activesnakesthataredifficulttocaptureandhandle.Sometimes,stressedindividualstruncatetheirtailsasadefensemechanism(Branch1999).
Lizards of the Plains GobabebCentrehasahighlizardspeciesdiversity.Inpar-ticular,SandLizards(Pedioplanisspp.),including NamaquaSandLizards (P. namaquensis) andSpottedSandLizards (P. lineoocellata)arecommonlyobservedsprintingrapidlybetweenloosestonesintheflatrockyveld.Whenapproach-ingtheminopenterrain,theyoftenfleetothenearestrockorburrow.SandLizardscanbeidentifiedlargelybytheirlong,slenderbodies,longtailsrelativetooverallbodylength,and
lightbrowncoloration.SpottedSandLizards mayactivelyforagethroughouttheyear,includingwarmwinterdays.Incontrast,P. namaquensis burrowsintodormancyduringthewinter(Branch1999).Underexperimentalconditions,P. namaquensiswasabletorecognizetheinherentdistributionofdifferentkindsofpreyinsects(Eifleretal.2012). We commonly encounteredWestern Three-StripedSkinks(Mabuya occidentalis;Fig.5)outsidethesparsevegeta-tionsurroundingtheresearchlibraryandoccasionallyevensprintingthroughourownvilla!Thesehardyskinksvaryincolorationfromblacktored-brownandolive-brown.Theyhibernatethroughthewinter,butlittleisknownabouttheirreproductive biology (Branch 1999).Unfortunately, weneverfoundaNamaquaChameleon(Chameleo namaquen-sis),althoughothers,includinglocalworkers,haveseenthemnearGobabeb.Thislarge-mouthedchameleonisprimarilyinsectivorous,consumingupto200beetlesdaily(Branch1999).Unlikeotherchameleons,itstailismuchshorterthantheoverallbodylengthandhardlyprehensile.
The Day and Night ShiftsGekkonidlizardscompriseoneofthelargestcomponentsoftheendemicsouthernAfricanherpetofauna,andtheNamibDesert isoneof theworld’shotspots for geckodiversity(Bauer1999).Thevaryingterrainfacilitateshabitatcomplex-ity.Peculiaramonggeckos,CommonNamibDayGeckos(Rhoptropus afer;Fig.6)sprintacrosslargerocksandseekshel-teramonglooserocksorcrevicesthroughouttheday.Duringmale-male interactions, individuals commonly performpush-upsandhead-bobbingwhilecompetingforterritories.Individualswereactiveonrocksubstrateswhentemperatureswereover30°C.Occupyingmanyofthesamerocksarenoc-turnallyactiveTurner’sThick-ToedGeckos(Chondrodactylus turneri),whichhavereducedbutuniquefootpadsthatarewelladaptedforclimbingverticalcrevices.ItslargerbodyanddarkerscaleseasilydistinguishitfromR. afer.
Scorpion SpecialistWithmorethan130knownspecies(Leeming2003),south-ernAfricaisoneoftheworld’sscorpionhotspots.Notsur-
Fig. 4.HornedAdders (Bitis caudalis)are small,heavy-bodiedviperswidelydistributedacrosssouthernAfrica.Addersfeedlargelyonvertebratepreyitemssuchaslizardsandshrews.ThedietofB. caudalisvariesdis-tinctlywithsize,sex,andgeographicdistribution(Shineetal.1998).
Fig. 5.TheWesternThree-StripedSkink(Mabuya occidentalis)canbeseennearmostrockyoutcrops,whereitactivelyforagesbetweencrevicesforarthropodandgekkonidprey.
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prisingly,Namibiahasvertebratesthatspecializeincaptur-ingandeatingthesewilyanddangerousarachnids(Leeming2003).Weadvisevisitingresearcherstoalwayswearclose-toedfootwearintheeveningandwalkwithaflashlighttopreventunexpectedencounterswith scorpionsand tobeonthealert,evenintheshower!TheGiantGroundGecko(Chondrodactylus anguilifer;Fig.7),anunusuallylarge,cylin-dricalgecko,isprimarilynocturnalandmaybefoundrest-inginoldscorpionburrowsduringtheday(Branch1999).Thesegekkonidtitansarebelievedtopreyheavilyonscor-pions.Althoughweobservedonlyafewindividuals,GiantGroundGeckosarehighlyconspicuouswiththeirlargebodysizes,vibrantcoloration,andstationarydefenseposture—withtailtipsslightlybentandlimbsraised,theyresemblescor-pions.Subspeciesvaryconsiderablyincoloration(browntopalepink)andevenbehavioralresponses(agonisticbitingtoratherdocile)dependingonthelocality(Branch1999).
“Bark, Bark,” says the GeckoThreespeciesofBarkingGecko(Ptenopusspp.;Fig.8) calltheNamibDeserthome.Asthenameimplies,CommonBarking
Geckos(P. garrulous),Koch’sBarkingGeckos(P. kochi), and Carp’sBarkingGeckos(P. carpi)allhavedistinctbarkingcalls.Forthemostpart,callsareemittedattheentrancesofburrowswhilebodiesarepartiallyemerged.Maleshaveyellowthroatpatchesthattheyrapidlyexpandanddeflate(Haacke1964).CommonBarkingGeckos(P. garrulus)differfromtheothertwospeciesbybeingtermitespecialistsandinthatmaleshavelargerheadsthanfemales.Inaddition,P. garrulus digsburrowsinloose,deepsoilandusuallyaddsbranchesforstructuralsupport(Hibbitsetal.2005). Koch’sBarkingGecko(P. kochi) broadlyresemblesP. garrulusingeneralappearance.However,uponcloserinspec-tion,P. kochiisstouterandtheyellowpigmentationinmalescontinuesbeyondthethroat,overthemouthregion,anddownthesidesofthebody(Branch1999),althoughtheyel-lowisbrightonthethroatandpaleelsewhere(Fig8a).Koch’sBarkingGeckoisfoundintheinterduneplains(Henscheletal.2006).Incontrast,endemicCarp’sBarkingGeckos(P. carpi)reside northoftheriverinthegravelplains,wheretheyburrowinhardersoilsthatusuallyaremixedwithsmallpebbles(Henscheletal.2006,Haacke1964).Distinctfrom
Fig. 6.TheCommonNamibDayGecko(Rhoptropus afer; left) iswidelydistributedthroughoutthegravelplains.Turner’sThick-ToedGecko(Chondrodactylus turneri;right)caneasilybelocatedatnightbyitsbrighteyeshine.
Fig. 7.TheGiantGroundGecko(Chondrodactylus anguilifer;left) likelycapitalizesonthescorpion-richsystemforprey,althoughthecommonBlackHairyThick-tailedScorpion(Parabuthus villosus;right)isnearfatalforhumansandmaybeariskymealevenforGiantGroundGeckos.
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theothertwobarkinggeckos,P. carpihasthesimplestburrowstructure,arguablybecauseofitshabitat-specificrequirements(Haacke1964).
Living DunesFromadistancethedunes(Fig.9)appearasmoundsofsedi-ment,yetupclosetheyhostcommunitiesofplants,inverte-brates,lizards,snakes,andevensomemammalsandbirds.Beetlesandotherinvertebratesusethesmallpocketsofveg-etationasrefugiafrompredatorsandtheheat.Infact,amajorsourceofthesoilnitrogenarisesfromtheuricacidwastedepositsexcretedbybeetles(HadleyandSzarek1981).Evenmoreinterestingaretheherpetologicalfood-webdynamics.AsingledunemayhostatleastthreetofivedifferentspeciesoflizardsalongwiththeoccasionalPsammophissandsnakeand
adder.Forinstance,Brain’sBlindLeglessSkink(Typhlosaurus braini)isanocturnallizardthatspendsitsentirelifebur-rowinginsandwhereitpreysoninsectlarvaeandtermites(Branch1999).Despiteitscommonlyvisibletracksalongthesurfaceofthedunes,ourattemptstocaptureT. brainiwithpittrapswereunfruitful.Littleisknownaboutthisparticularskink,makingitagreattargetfornaturalhistoryorbehavioralresearch.
Web-footed GeckoTheNamibDuneGecko (Palmatogecko rangei; Fig. 10) standsoutforitsuniquelifehistoryandspecializedmor-phological adaptations.Even though their appearance isdistinct frommanyothergeckospecies, theyareactuallycloselyrelatedtotheThick-toedGeckos(Chondrodactylus spp.;Branch1999).Thesemitransparent,pink-tancolor-ationofP. rangeiblendswiththedunes.Perfectlyadaptedtoaridhabitats,theyacquirewaterthroughfogabsorptionandthefoodtheyconsume(Branch1999).Fogaccumulatesandthesandishighlycompactedfromwindandmoisture
Fig. 8.BoththeCommonBarkingGecko(Ptenopus garrulous;left)andKoch’sBarkingGecko(P. kochi;right)feedoninvertebratesandoccasionallyveg-etation.BarkingGeckosarethemostcommonnocturnalreptilesintheNamibDesert,wheretheyserveaspreyforpredatoryvertebratesaswellasWhiteLadySpiders(Leucorchestris arenicola;Cloudsley-Thompson1991).
Fig. 9.Strongdirectionalwindpatternsinsand-limitedenvironmentsformhalf-moonshapeddunesknownasbarchans.IntheNamibDesert,thesepanoramicdunescanrangefromafewhundredmeterstoalmost200kminlengthandfrom200to300minheight(Middleton2009).Ifyouareobservingdiurnallizardactivity,leaveearlyinthemorningandseekshadebeforethemiddleofthedaywhensubstratetemperaturescanreachwellover35°C.
Fig. 10.NamibDuneGeckos(Palmatogecko rangei)arefrequentlyencoun-teredalongthedunesintheevening.However,catchingthesegeckoscanberatherdifficultastheycansprintanddigrapidlythroughthesand;pursuingtheminsmallgroupsworkswell.
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atthelowerbasesofduneswheretheyoccur,(RussellandBauer1990).Theirdistinctivewebbedtoepads,whichlikelyemergedastheirclawswerereducedoverevolutionarytime,notonlyfunctionassnowshoe-likemorphologicalstructuresforglidingalongthesand,buttheycanalsoserveasshovelsforsiftingthroughsandduringburrowconstruction(RussellandBauer1990).Amazingly,thespanoftheirfeetcanreach236°,providingthemwiththegreatestdigitalspanofallrep-tilesknowntoman(RussellandBauer1990)!
Shovel versus WedgeThe Shovel-snouted Lizard (Meroles anchietae) and theWedge-snouted Lizard (Meroles cuneirostris) are closelyrelatedphylogeneticallybutvarydistinctly in theirmor-phology(Fig.11).Thecommonnamesreflecttheshapesoftheirheads.Additionally,M. anchiteae(SVL:M=49mmandF=44mm)areonaveragesmallerthanM. cuneirostris (SVL:M=54mmandF=49mm;GoldbergandRobinson1979).Theirsnoutsandlong,thinhindlegsallowthemtomaneuverquicklythroughsandtoescapedeadlyheatandabundantpredators(Branch1999).Wedge-snoutedLizards(M. cuneirostris;Fig.12)occupythelowerbasesofthesanddunes,frequentlyneartheKuisebriverbed.Theyoftenforageintheinterduneplains,wherethehabitatisflat,sandy,and
vegetated,andarehosttoavarietyofinsects(GoldbergandRobinson1979).Incontrast,M. anchietaeisprimarilyfoundonsteepslopesoftheduneswherevegetationisminimal.Theirdietconsistsmainlyoftwospeciesofarthropodsandseedsthataredispersedbythewind(GoldbergandRobinson1979).However,bothoftheselacertidsexhibithigh-speedlocomotionacrosssandviathefringedtoes,amechanismprovidingforboththermalregulationandpredatoravoid-ance(Branch1999).Apparently,theadvantageofashovel-orwedge-shapedsnoutreliesonthedistinctsandymicrohabitatsofthedunes.
DiscussionOverall,TheGobabebResearchandTrainingCentreisaprimeresearchfacilityforfieldworknotonlybecauseofitshighreptilediversity,butalsoduetoitsstrongemphasisoncollaborationand sustainability—conservingwater andexploitingsunlightforelectricityinafragilelandscape.WehighlyrecommendabriefvisittoGobabebtoviewandlearn
Fig. 11.BothWedge-snoutedDesertLizards(Meroles cunirostris;left)andShovel-snoutedLizards(M. anchietae;right)diveintosandtoescapepredators.Patchyvegetationonthedunesisanoasisforbiologicalactivity,aslizardsforageinthebrushforarthropodswhilesnakessearchforlizards.
Fig. 12.TheWedge-snoutedDesertLizard(Meroles cunirostris;left)isacommonpreyitemfortheCapeSandSnake(Psammophis leightoni)onthelowerstretchesofthedunes.Thecoloredbeadsarefromapreviousmark-recapturestudy.
Fig. 13.TheErellInstitutehostedamotleycrewofwildlifeenthusiasts,eagertolearnabouttheherpetofaunaoftheNamibDesert.Studentsrep-resentedmanynations:Botswana,Cherokee,Cheyenne,Chickasaw,Hopi,Namibia,ThreeAffiliatedTribes,andYaqui.“Educationisyourgreatestweapon.Idonotthinkthemeasureofacivilizationishowtallitsbuildingsofconcreteare,butratherhowwellitspeoplehavelearnedtorelatetotheirenvironmentandfellowman.”—SunBear(Chippewa).
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abouttheirprogressiveapproachtosustainability,experiencetheirwelcomingcommunity,andimmerseyourselfintheregion’suniquebiodiversity.
AcknowledgementsWearegrateful to theefficientandaccommodatingstaffandadministrationoftheGobabebResearchandTrainingCentre.TheNationalScienceFoundationprovidedfundingfortravel,researchsupplies,andstipends.TheErellInstituteorganizedthisundergraduateresearchexperiencewhilefoster-inglife-longconnectionsforindigenousstudentsfromtheUnitedStates,Namibia,andBotswana(Fig.13).
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