Iguana b&w text 178 IGUANA • VOLUME 13, NUMBER 3 • SEPTEMBER 2006 ARIANO-SÁNCHEZ Guatemalan Beaded Lizards (Heloderma horridum charlesbogerti) are endemic to the semiarid Motagua Valley in Guatemala. TO M M Y O W EN S, S A N D IE G O Z O O Iguana 13.3 b&w text.QX6 9/17/06 3:02 PM Page 178 The semiarid Motagua Valley in Guatemala is one of the most endangered and unique ecosystems in the world. This region receives the lowest average rainfall in Central America (ca. 500 mm) and is characterized by many endemic species. This region once occupied about 200,000 ha, most of which is now a heterogeneous landscape of crops, grasslands, thornscrub, and very dry deciduous forest remnants. The latter are home to the very rarely encountered endemic Guatemalan Beaded Lizard (Heloderma horridum charlesbogerti). Natural History The Guatemalan Beaded Lizard, which (in conjunction with H. h. alvarezi) may actually represent a distinct species, is restricted to forest remnants in the Motagua Valley. The Beaded Lizards and 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 not been studied until very recently. This species reduces its activity drastically during the dry season (December to May), when individuals remain almost constantly concealed in subterranean shelters that provide pro- tection from extreme temperatures and desiccation. Suitable shelters are limited resources in the remaining forests and may limit 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 in the wild. Only 24,000 ha of suitable habitat remain, and these are comprised of patches ranging in size from < 1 ha to around 1,500 ha. If only those patches of > 100 ha are considered, the potential distribution of these lizards is reduced to 17,000 ha. This area comprises the localities of Cabañas, Usumatlán, and Gualán in the Zacapa Department, and El Jicaro in the El Progreso Department, in the semiarid region of the Motagua Valley in Guatemala. Conservation Status The Guatemalan Beaded Lizard is almost certainly the most endangered species in Guatemala. It is listed in CITES Appendix II and as vulnerable in the IUCN Red List of Threatened 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 Ecosystem Daniel Ariano-Sánchez Director, Research & Conservation Projects Zootropic Organization Ciudad Guatemala, Guatemala dariano@zootropic.com Photographs by the author except where indicated. IGUANA • VOLUME 13, NUMBER 3 • SEPTEMBER 2006 179GUATEMALAN BEADED LIZARD � A 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 179 tion, illegal extraction for local and international collectors, and persecution 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 locality killed 11 lizards. Another factor that may have had a negative impact on wild populations of H. h. charlesbogerti was Hurricane Mitch in November 1998. Vast zones of the most arid portions of the Motagua Valley were flooded that year, causing considerable damage to the human population and to the wildlife of the region. Late October-early November is the beginning of the egg-laying season for Beaded Lizards, and the eggs are known to be very sensitive to humidity. A number of clutches may well have been lost or failed to hatch because of floods. Unfortunately, no baseline data existed at that time, so the impact on wild populations cannot be evaluated. Conservation Efforts Since the initiation of intensive studies in 2002, conservation efforts have increased, in part because of an increased public awareness regarding the threatened status of the species. These efforts 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. Research has focused on determining distribution, the nature and cause of 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 in coordination with local authorities and local partners of Zootropic. The habitat conservation component has two approaches: (1) conservation of private lands by commitment of owners to preserve forest remnants and (2) an official declara- tion of municipal, communal, and private natural reserves as 180 IGUANA • VOLUME 13, NUMBER 3 • SEPTEMBER 2006 ARIANO-SÁNCHEZ Guatemalan Beaded Lizards (Heloderma horridum charlesbogerti) emerging from and resting in subterranean shelters. L. M EL EN D EZ , Z O O TR O PI C Land-use changes within the distribution of Heloderma horridum charlesbogerti: Changes are primarily attributable to production of com- mercial crops like melon (top) and subsistence crops like corn (bottom). L. M EL EN D EZ , Z O O TR O PI C Iguana 13.3 b&w text.QX6 9/17/06 3:02 PM Page 180 IGUANA • VOLUME 13, NUMBER 3 • SEPTEMBER 2006 181GUATEMALAN BEADED LIZARD part of the Guatemalan protected areas system. Finally, Zootropic has promoted and coordinated the planning of a national strategy for Guatemalan Beaded Lizard conservation with the support of The Nature Conservancy. This conservation plan was generated in collaboration with local and international experts representing 16 institutions, including the National Council of Protected Areas (CONAP), which is Guatemala’s official institution in charge of biodiversity conservation. Local People: Poachers and Conservationists Considering that two of the most serious threats to the species are illegal trade and extermination, environmental education has been strongly emphasized. This program actively engages local people, some of whom were poachers of Heloderma in the past. Today, they are proud conservationists. Demonstrating the uniqueness and importance of conserving this species, locals have learned that many of the myths associated with the species were not true. Some individuals have learned to use the radioteleme- try equipment and implement basic research techniques. The principal objective of this involvement is to incorporate members of the community in the research in order to instill an apprecia- tion for this species. Only with a strong relationship between locals 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 the map). 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 patterns and shelter selection in the wild L. M EL EN D EZ , Z O O TR O PI C Iguana 13.3 b&w text.QX6 9/17/06 3:02 PM Page 181 182 IGUANA • VOLUME 13, NUMBER 3 • SEPTEMBER 2006 ARIANO-SÁNCHEZ Next Steps In spite of strong conservation efforts already implemented, gaps still exist in the data. Very little is known, for instance, about the species’ ecology, characteristics of the nests, and which specific phys- ical factors affect shelter selection. Reproductive behavior has not been observed or documented in the wild. Such data are of great importance 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 this species to official environmental agencies. A captive-breeding pro- gram has been initiated. Within the year, genetic analyses of wild and captive populations are slated to begin. A group of local and international experts (representing 16 institutions) are collectively responsible for the National Strategy for Guatemalan Beaded Lizard Conservation. L. M EL EN D EZ , Z O O TR O PI C The environmental education program addresses local farmers (top) and school children (bottom). A . G O N ZA LE S, Z O O TR O PI C A 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 182 IGUANA • VOLUME 13, NUMBER 3 • SEPTEMBER 2006 183GUATEMALAN BEADED LIZARD Acknowledgements I thank Daniel Beck, Brad Lock, and John Binns for information and suggestions that improved this paper. I thank Lester Melendez for the use of some photographs, and all the institutions and persons that supported this project at different times: Craig Ivanyi (Arizona- Sonora Desert Museum), Atlanta Zoo, Idea Wild, German Academic Exchange Service, The Nature Conservancy, National Fund for Nature Conservation (FONACON), National Council of Protected Areas (CONAP), Nature Defenders Foundation (FDN), University of the Valley of Guatemala (UVG), University of Costa Rica (UCR), and especially Gilberto Salazar, Luis Alvarado, Antonio Urbina, Rodrigo Botrán, and Alejandro Gonzalez from from Zootropic for supporting, participating, and believing in this project. References Ariano, D. 2003. Distribución e Historia Natural del Escorpión Heloderma hor- ridum charlesbogerti Campbell y Vannini (Sauria: Helodermatidae) en Zacapa, Guatemala y caracterización de su veneno. Licenciatura Thesis, Universidad del Valle de Guatemala, Guatemala. Ariano, D. In prep. Distribucion potencial, uso de refugios y comportamiento del lagarto Escorpión, Heloderma horridum charlesbogerti. MSc. Thesis, Universidad de Costa Rica, San José. Ariano, D. and L. Masaya. 2005. Estado poblacional actual e historia natural del Escorpión, Heloderma horridum charlesbogerti Campbell y Vannini, (Sauria: Helodermatidae) en Cabañas, Zacapa, Guatemala: Informe Final de Consultoría. Zootropic y The Nature Conservancy, Guatemala. Beck, D.D. 2005. Biology of Gila Monsters and Beaded Lizards. University of California Press, Berkley and Los Angeles. Beck, D.D. and R.D. Jennings. 2003. Habitat use by Gila monsters: The importance of shelters. Herpetological Monographs 17: 112–130. Bulova, S. 1994. Patterns of burrow use by Desert Tortoises: Gender differences and 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 of Herpetology 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 de Conservación 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 microhabitat utilization. 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 Beaded Lizards. Iguana 13.3 b&w text.QX6 9/17/06 3:02 PM Page 183