Ariano-Sánchez, Daniel

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178 IGUANA  •  VOLUME 13, NUMBER 3  •  SEPTEMBER 2006 ARIANO-SÁNCHEZGuatemalan Beaded Lizards (Heloderma horridum charlesbogerti) are endemic to the semiarid Motagua Valley in Guatemala.TOMMY OWENS, SAN DIEGO ZOOIguana 13.3 b&w text.QX6  9/17/06  3:02 PM  Page 178The semiarid Motagua Valley in Guatemala is one of themost endangered and unique ecosystems in the world. Thisregion receives the lowest average rainfall in Central America (ca.500 mm) and is characterized by many endemic species. Thisregion once occupied about 200,000 ha, most of which is nowa heterogeneous landscape of crops, grasslands, thornscrub, andvery dry deciduous forest remnants. The latter are home to thevery rarely encountered endemic Guatemalan Beaded Lizard(Heloderma horridum charlesbogerti).Natural HistoryThe Guatemalan Beaded Lizard, which (in conjunction with H.h. alvarezi) may actually represent a distinct species, is restrictedto forest remnants in the Motagua Valley. The Beaded Lizardsand Gila Monsters (H. suspectum) comprise the Helodermatidae,a unique family of lizards with venom glands. Although the sub-species H. h. charlesbogerti was described in 1988, it had notbeen studied until very recently.This species reduces its activity drastically during the dryseason (December to May), when individuals remain almostconstantly concealed in subterranean shelters that provide pro-tection from extreme temperatures and desiccation. Suitableshelters are limited resources in the remaining forests and maylimit population size. Recent estimates, based on average home-range sizes of this and other subspecies and on remaining avail-able habitat, suggest that only 200–250 individuals remain inthe wild.Only 24,000 ha of suitable habitat remain, and these arecomprised of patches ranging in size from < 1 ha to around1,500 ha. If only those patches of > 100 ha are considered, thepotential distribution of these lizards is reduced to 17,000 ha.This area comprises the localities of Cabañas, Usumatlán, andGualán in the Zacapa Department, and El Jicaro in the ElProgreso Department, in the semiarid region of the MotaguaValley in Guatemala.Conservation StatusThe Guatemalan Beaded Lizard is almost certainly the mostendangered species in Guatemala. It is listed in CITESAppendix II and as vulnerable in the IUCN Red List ofThreatened species. The greatest threats to its continued exis-tence are agricultural practices not compatible with conserva-The Guatemalan Beaded Lizard:Endangered Inhabitant of a Unique EcosystemDaniel Ariano-SánchezDirector, Research & Conservation ProjectsZootropic OrganizationCiudad Guatemala, Guatemaladariano@zootropic.comPhotographs by the author except where indicated.IGUANA  •  VOLUME 13, NUMBER 3  •  SEPTEMBER 2006 179GUATEMALAN BEADED LIZARDA female Guatemalan Beaded Lizard (Heloderma horridum charles-bogerti) in the wild.Iguana 13.3 b&w text.QX6  9/17/06  3:02 PM  Page 179tion, illegal extraction for local and international collectors, andpersecution by local people, who consider it to be dangerous.From 1994–2000, an estimated 30 animals were illegally col-lected, and, from 2000–2001, local people at only one localitykilled 11 lizards.Another factor that may have had a negative impact onwild populations of H. h. charlesbogerti was Hurricane Mitch inNovember 1998. Vast zones of the most arid portions of theMotagua Valley were flooded that year, causing considerabledamage to the human population and to the wildlife of theregion. Late October-early November is the beginning of theegg-laying season for Beaded Lizards, and the eggs are known tobe very sensitive to humidity. A number of clutches may wellhave been lost or failed to hatch because of floods.Unfortunately, no baseline data existed at that time, so theimpact on wild populations cannot be evaluated.Conservation EffortsSince the initiation of intensive studies in 2002, conservationefforts have increased, in part because of an increased publicawareness regarding the threatened status of the species. Theseefforts have been led by a local NGO, “Zootropic.” The pro-gram is constituted of four basic elements: (1) education, (2)applied scientific research, (3) habitat conservation, and (4)development of conservation policies for this species. Researchhas focused on determining distribution, the nature and causeof threats, the basic biology of the species, movement patterns,shelter use and their availability as a limiting resource, and char-acterization of venom. The education program has been ongo-ing since mid-2003 in localities where this species occurs and incoordination with local authorities and local partners ofZootropic. The habitat conservation component has twoapproaches: (1) conservation of private lands by commitment ofowners to preserve forest remnants and (2) an official declara-tion of municipal, communal, and private natural reserves as180 IGUANA  •  VOLUME 13, NUMBER 3  •  SEPTEMBER 2006 ARIANO-SÁNCHEZGuatemalan Beaded Lizards (Heloderma horridum charlesbogerti)emerging from and resting in subterranean shelters.L. MELENDEZ, ZOOTROPICLand-use changes within the distribution of Heloderma horridumcharlesbogerti: Changes are primarily attributable to production of com-mercial crops like melon (top) and subsistence crops like corn (bottom).L. MELENDEZ, ZOOTROPICIguana 13.3 b&w text.QX6  9/17/06  3:02 PM  Page 180IGUANA  •  VOLUME 13, NUMBER 3  •  SEPTEMBER 2006 181GUATEMALAN BEADED LIZARDpart of the Guatemalan protected areas system. Finally,Zootropic has promoted and coordinated the planning of anational strategy for Guatemalan Beaded Lizard conservationwith the support of The Nature Conservancy. This conservationplan was generated in collaboration with local and internationalexperts representing 16 institutions, including the NationalCouncil of Protected Areas (CONAP), which is Guatemala’sofficial institution in charge of biodiversity conservation.Local People: Poachers and ConservationistsConsidering that two of the most serious threats to the speciesare illegal trade and extermination, environmental education hasbeen strongly emphasized. This program actively engages localpeople, some of whom were poachers of Heloderma in the past.Today, they are proud conservationists. Demonstrating theuniqueness and importance of conserving this species, locals havelearned that many of the myths associated with the species werenot true. Some individuals have learned to use the radioteleme-try equipment and implement basic research techniques. Theprincipal objective of this involvement is to incorporate membersof the community in the research in order to instill an apprecia-tion for this species. Only with a strong relationship betweenlocals and scientific researchers is an understanding of the impor-tance of the project possible. These people now function as pro-moters of the conservation plan within their own communities.Potential distribution of Heloderma horridum charlesbogerti in the semiarid Motagua Valley in Guatemala (indicated by the shaded area on themap). Determination of the potential distribution took into account historical and recent collection sites, land use patterns, rainfall and tempera-ture data, forest types, and distances to human settlements.Current research is using radiotelemetry to reveal movement patternsand shelter selection in the wildL. MELENDEZ, ZOOTROPICIguana 13.3 b&w text.QX6  9/17/06  3:02 PM  Page 181182 IGUANA  •  VOLUME 13, NUMBER 3  •  SEPTEMBER 2006 ARIANO-SÁNCHEZNext StepsIn spite of strong conservation efforts already implemented, gapsstill exist in the data. Very little is known, for instance, about thespecies’ ecology, characteristics of the nests, and which specific phys-ical factors affect shelter selection. Reproductive behavior has notbeen observed or documented in the wild. Such data are of greatimportance for implementing ex situ and in situ conservation strate-gies. Also, emphasis continues on strengthening environmental edu-cation programs and continuing to promote the conservation of thisspecies to official environmental agencies. A captive-breeding pro-gram has been initiated. Within the year, genetic analyses of wildand captive populations are slated to begin.A group of local and international experts (representing 16 institutions)are collectively responsible for the National Strategy for GuatemalanBeaded Lizard Conservation.L. MELENDEZ, ZOOTROPICThe environmental education program addresses local farmers (top)and school children (bottom).A. GONZALES, ZOOTROPICA Heloderma horridum charlesbogerti with a radiotransmiter is entering a subterranean shelter.Iguana 13.3 b&w text.QX6  9/17/06  3:02 PM  Page 182IGUANA  •  VOLUME 13, NUMBER 3  •  SEPTEMBER 2006 183GUATEMALAN BEADED LIZARDAcknowledgementsI thank Daniel Beck, Brad Lock, and John Binns for information andsuggestions that improved this paper. I thank Lester Melendez for theuse of some photographs, and all the institutions and persons thatsupported this project at different times: Craig Ivanyi (Arizona-Sonora Desert Museum), Atlanta Zoo, Idea Wild, GermanAcademic Exchange Service, The Nature Conservancy, NationalFund for Nature Conservation (FONACON), National Council ofProtected Areas (CONAP), Nature Defenders Foundation (FDN),University of the Valley of Guatemala (UVG), University of CostaRica (UCR), and especially Gilberto Salazar, Luis Alvarado, AntonioUrbina, Rodrigo Botrán, and Alejandro Gonzalez from fromZootropic for supporting, participating, and believing in this project.ReferencesAriano, D. 2003. Distribución e Historia Natural del Escorpión Heloderma hor-ridum charlesbogerti Campbell y Vannini (Sauria: Helodermatidae) enZacapa, Guatemala y caracterización de su veneno. Licenciatura Thesis,Universidad del Valle de Guatemala, Guatemala.Ariano, D. In prep. Distribucion potencial, uso de refugios y comportamientodel lagarto Escorpión, Heloderma horridum charlesbogerti. MSc. Thesis,Universidad de Costa Rica, San José.Ariano, D. and L. Masaya. 2005. Estado poblacional actual e historia naturaldel Escorpión, Heloderma horridum charlesbogerti Campbell y Vannini,(Sauria: Helodermatidae) en Cabañas, Zacapa, Guatemala: Informe Finalde Consultoría. Zootropic y The Nature Conservancy, Guatemala.Beck, D.D. 2005. Biology of Gila Monsters and Beaded Lizards. University ofCalifornia Press, Berkley and Los Angeles.Beck, D.D. and R.D. Jennings. 2003. Habitat use by Gila monsters: Theimportance of shelters. Herpetological Monographs 17: 112–130.Bulova, S. 1994. Patterns of burrow use by Desert Tortoises: Gender differencesand seasonal trends. Herpetological Monographs 8: 133–143.Campbell, J. and J. Vannini. 1988. A new subspecies of Beaded Lizard,Heloderma horridum, from the Motagua Valley of Guatemala. Journal ofHerpetology 22: 457–468.Dinerstein, E., D.M. Olson, D.J. Graham, A.L. Webster, S.A. Primm, M.P.Bookbinder, and G. Ledec. 1995. Una Evaluación del Estado deConservación de las Ecoregiones Terrestres de América Latina y el Caribe.World Bank, WWF, Washington, D.C.Douglas, M., R. Douglas, G. Schuett, D. Beck, and B. Sullivan. 2003.Molecular biodiversity of Helodermatidae (Reptilia, Squamata). Abstract.Program, Joint Meeting of Ichthyologists and Herpetologists, Manaus,Amazonas, Brasil.Zimmerman, L., M. O’Conner, S. Bulova, J. Spotila, S. Kemp, and C. Salice.1994. Thermal ecology of Desert Tortoises in the eastern Mojave Desert:Seasonal patterns of operative and body temperatures, and microhabitatutilization. Herpetological Monographs 8: 45–59.Land owners have designated forest remnants on their farms for protection; this large remnant near El Arenal is inhabited by Guatemalan BeadedLizards.Iguana 13.3 b&w text.QX6  9/17/06  3:02 PM  Page 183

The Guatemalan Beaded Lizard: Endangered Inhabitant of a Unique Ecosystem

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The Guatemalan Beaded Lizard: Endangered Inhabitant of a Unique Ecosystem

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