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side the third burrow and began a foot-drumming display (Kenagy1976. J. Mammal. 57:781–785; Randall and Matocq 1997. Behav.Ecol. 8:404–413.) in which she rapidly and repeatedly beat herfeet against the sand.The remaining pups inside the second burrow were squeaking,and the mother returned and moved quickly into the burrow withboth the remaining two visible pups and the H. suspectum. At 0807h, the mother emerged from the second burrow (without any pups)and moved over to the third burrow where she had left the rescuedpup. At 0820 h, the mother left the third burrow without her pupand moved out of sight. For 20 min, the H. suspectum remainedinside the second burrow. At 0840 h, squeaking noises emanatedfrom the third burrow where the Desert Kangaroo Rat mother hadplaced the rescued pup. The Gila Monster remained undergroundin the second burrow until 0923 h, and then emerged from theburrow (Fig. 2d) and walked to, and into, the third burrow, whereit presumably consumed the rescued pup. The H. suspectum remainedinside the third burrow for ca. 30 min and then emergedabove ground. After walking a few steps, the H. suspectum lickedits face and arched its back with snout pointed upward, a postureGila Monsters often assume after eating large meals (pers. obs.;Beck 2005, op. cit.). This arching posture may help force fooditems down into the stomach, especially when the stomach is alreadyfull.We were also able to verify nest predation by three other GilaMonsters on kangaroo rats at this Nevada site on four additionaloccasions. Each time, we were able to verify the genus of the prey(Dipodomys) by observing adults leaving the nest or pups attemptingto crawl out of the burrow. Most of the time we were not ableto identify Dipodomys to species, as the adults fled the nest once itwas discovered, and Gila Monsters immediately consumed thepups. The possible kangaroo rat species in this area include D.deserti and D. merriami (Hall 1946. Mammals of Nevada. Universityof California Press, Berkeley. 710 pp.), but because theseobservations were made as part of a larger natural history study ofNevada H. suspectum, we did not interfere with lizard foragingactivities to determine which of the two Dipodomys species wereinvolved. However, the observation of 19 June 2003 is undoubtedlya nest of D. deserti, as the kangaroo rat we observed waslarge and had white hairs on the terminal end of its tail (D. merriamiare smaller and have black terminal tail hairs).These six observations suggest that kangaroo rats can constitutean important part of the diet for certain populations of GilaMonsters. Our study site had a considerable amount of sand dunesand Creosote Bush (Larrea tridentata), both of which are appropriatehabitat elements for Dipodomys (Longland and Price 1991.Ecology 72:2261–2273; Schroder 1987. Ecology 68:1071–1083).Most previous ecological studies of Gila Monsters have been conductedat sites lacking sand dunes (Beck 2005, op. cit.), henceDipodomys might not be available prey to those populations. Additionally,our Nevada study site lacks conspicuous populationsof Desert Cottontail Rabbits (S. audubonii), which constitute themost common food item at other study populations of Gila Monsters(populations in Arizona and Utah; Beck 2005, op. cit.).We thank Ned Dochtermann and Kellie Kuhn for reading earlydrafts of the manuscript. The Clark County (Nevada) Multi-speciesHabitat Conservation Program and the Biological ResourcesResearch Center at UNR provided funding.Submitted by C. M. GIENGER and C. RICHARD TRACY,Program in Ecology, Evolution, and Conservation Biology, Departmentof Biology, University of Nevada, Reno, Reno, Nevada89557, USA (e-mail [CMG]: gienger@biodiversity.unr.edu).HEMIDACTYLUS MABOUIA (Tropical House Gecko). HU-MAN-INDUCED INTRODUCTION. Hemidactylus mabouiaoccurs in urban and other anthropogenic environments as well asvaried less disturbed habitats such as tropical rainforest, sand dunesand rock outcrops (Teixeira 2001. Atlântica 23:77–84). A smalllizard native to sub-Saharan Africa, it was accidentally introducedto and has colonized most of the South and Central America andFlorida (Butterfield et al. 1993. Herpetol. Rev. 24:111–112), Caribbeanislands (Townsend and Krysko 2003. Florida Scient.66:204–208), and Atlantic islands such as Cape Verde (Jesus et al.2001. J. Herpetol. 35:672–675), Madeira (Jesus et al. 2002.Herpetozoa 15:179–180), São Thomé and Príncipe (Jesus et al.2005. Mol. Phylogenet. Evol. 34:480–485), and the Abrolhos Archipelago,70 km off the Brazilian coast (Rocha et al. 2002. Braz.J. Biol. 62:285–291). Populations in the Gulf of Guinea andMacronesian islands are genetically homogenous likely as a resultof recent introductions (Jesus et al. 2005, op. cit.). Introductionto the Brazilian mainland likely occurred through slave shipsfrom Africa (Vanzolini 1968. Arq. Zool. São Paulo 17:1–84). Here,we describe the recent colonization of the oceanic Trindade Islandin the mid-Atlantic Ocean and discuss the likely introduction event.Trindade Island, located 1140 km off the Brazilian coast, is a smallvolcanic island (5 km × 2.5 km) with an area of 13.5 km 2 andelevations over 600 m (Almeida et al. 2001. In Schobbenhaus etal. [eds.], Sítios Geológicos e Paleontológicos do Brasil, pp. 369–377. DNPM, Brasília, Brazil). Originally covered by forests ofColubrina glandulosa, fire and domestic grazing (sheep and goats)drove this tree to extinction (Alves 1998. Ilha da Trindade &Arquipélago de Martin Vaz, um Ensaio Geobotânico. Serviço deDocumentação da Marinha, Rio de Janeiro, Brazil). Reforestationwas begun in 1994, and eradication of goats occurred over theinterval 1999–2005 (Alves 2006. In Alves and Castro [eds.], IlhasOceânicas Brasileiras, da Pesquisa ao Manejo, pp. 83–104. MMA,Brasília, Brazil). Both these domestic grazers are now eradicated,but despite its success, reforestation has ceased. Apart from humans,the only terrestrial vertebrate on Trindade Island is the exoticHouse Mouse, Mus musculus, which is now abundant throughoutthe island. Since 1957, a small number of Navy personnel (currently~25 people) who maintain a weather station live on TrindadeIsland. A boat transports food, equipment, and personnel to theisland every two months.We first observed H. mabouia at dusk on 31 December 2006 ona plateau above Príncipe Beach (20.5165°S, 29.3096°W; datum:Córrego Alegre; elev. 140 m) in rock outcrops bordered by thedense, tall (ca. 50 cm high) sedge, Cyperus atlanticus. The nextday, we captured one H. mabouia and found one semi-buried clutchof two eggs and a second clutch of three eggs, both under rocks.Because this species typically deposits two eggs, this may havebeen a communal nest (Rocha et al., op. cit.). After this initialdiscovery, we made several subsequent observations of adults andjuveniles. From January to April 2007, we found up to 10 individualsduring search sessions lasting about 1 h, with higher num-226 Herpetological Review 39(2), 2008