First report of the Southern Gulf Coast Toad (Incilius valliceps Wiegmann), Common House Gecko (Hemidactylus frenatus Duméril and Bibron), Schmidt’s Black-Striped Snake (Coniophanes schmidti Bailey), and Cozumel Whiptail (Aspidoscelis cozumela Gadow), on Turneffe Atoll, Belize

Each year from 2012 to 2019, during a 12-day period in November or December, we photographed common herpetofauna on Calabash Caye, a small mangrove-dominated island on the eastern edge of Turneffe Atoll, Belize. Turneffe Atoll is home to the newest, largest, and most biodiverse marine protected area in Belize. Calabash Caye exemplifies the islands on Turneffe’s eastern edge whose elevated beach ridges enable the development of coastal strand plain and littoral forest habitats, which are among the most threatened habitats in the world. As no herpetofaunal survey has been published for Turneffe in over twenty years, and as the herpetofauna is a conspicuous indicator of the health of terrestrial ecological communities on islands, we leveraged our annual field excursions to Calabash Caye to compile a photographic record of the island’s reptiles and amphibians. In multiple years, we documented the presence of five lizards (Anolis sagrei mayensis, Aspidoscelis cozumela, Ctenosaura similis, Phyllodactylus tuberculosus, and the invasive species Hemidactylus frenatus), three snakes (Boa imperator, Leptophis mexicanus hoeversi, and Coniophanes schmidti), and one amphibian (Incilius valliceps). This represents the first report of A. cozumela, H. frenatus, C. schmidti, and I. valliceps on Calabash Caye or on any island in Turneffe Atoll; H. frenatus, C. schmidti, and I. valliceps have never been reported on any of the Belizean cayes. We did not observe four species that have previously been reported on Calabash Caye: Brown Basilisk (Basiliscus vittatus), Mesoamerican Cane Toad (Rhinella horribilis), Mayan Skink (Marisora lineola; formerly Mabuya unimarginata), or a blindsnake, provisionally identified as Indotyphlops braminus. We also include photos of Anolis allisoni, Ctenosaura similis, and Anolis sagrei mayensis obtained during four single-day excursions to Half Moon Caye on Lighthouse Atoll; this represents three of four species reported from that location during the 1990s.

Changes in escape behaviour of black iguanas (Ctenosaura similis) over an anthropogenic disturbance gradient

Studies on the impact of human activity on animal behaviour are critical for understanding the extent to which humans affect ecological dynamics. Previous studies have found that human presence alters antipredator behaviours, which can be measured by flight initiation distance (FID). We investigated escape behaviour of 96 black iguanas (Ctenosaura similis) across a gradient of human disturbance in six sites inside a protected area in Costa Rica. We used a field experiment to test for effect of human disturbance on FID. We found that individuals from higher disturbance sites had shorter FIDs, meaning that black iguanas from disturbed areas allow closer approaches. This finding is consistent with the prediction that some animals become more habituated to human presence as the degree of human disturbance increases. We propose that black iguanas’ ability to alter their behaviour in response to humans’ presence could make them especially adept at invading new environments.

SEGREGACIÓN DE HÁBITAT DE INDIVIDUOS ADULTOS Y JUVENILES DEL GARROBO Ctenosaura similis EN EL PARQUE NACIONAL SANTA ROSA, GUANACASTE, COSTA RICA.

Analizamos la distribución del garrobo Ctenosaura similis en tres tipos de hábitat del Parque Nacional Santa Rosa, Costa Rica: área abierta, área boscosa y área administrativa (suburbana). Registramos 101 individuos de los que un 32.7% eran hembras, 19.8% machos y 47.5% de sexo indeterminado. Registramos 58 individuos adultos y 43 individuos juveniles. El número de individuos adultos fue diferente al número de individuos juveniles (X²=8.21, df=2, p=0.02). Igualmente, la distribución de individuos por edad y apertura del dosel fue diferente (X²=20.97, df=4, p= < 0.001). En contraste, la cantidad de individuos por edad y tipo de sustrato fue igual (X²=3.12, df=3, p=0.37), tanto los individuos juveniles como los adultos se encontraron mayoritariamente en el suelo. Concluimos que los garrobos se segregan por edad y tipos de hábitat. Es posible que esta segregación esté determinada por la disponibilidad de recursos alimentarios y características del hábitat.

NATURAL HISTORY OF THE BLACK IGUANA Ctenosaura similis (SQUAMATA: IGUANIDAE) IN ISLA CONTOY, QUINTANA ROO, MEXICO

The genera Iguanaand Ctenosaurabelong to the Iguanidae family, and populations of most species of these genera have decreased due to anthropogenic effects. The natural history of most species of this family is poorly known, including Ctenosaura similis. Therefore, this study documents some ecological aspects of the species, such as its feeding habits, and habitat and microhabitat use in a population on Isla Contoy in Quintana Roo, Mexico. The data showed that even though C. similisis distributed throughout the island, individuals more commonly use human construction (buildings) of Parque Nacional Isla Contoy (PNIC) and mangrove areas. Microhabitats most used by all age classes and sexes were rocks and trees. The diet of the species is omnivorous; however, the frequency of prey type consumed changes with the age of the individuals (hatchlings, juveniles, and adults), as well as with the season of the year. The practice of cannibalism by some individuals is also reported, as well as coprophagy and scavenging. This work provides general information on the life history of C. similis, complementing the scarce information that is currently available.

Conocimiento etnozoológico de la herpetofauna de la comunidad maya de Santa Elena, Yucatán, México

Los anfibios y reptiles son organismos indispensables para el buen funcionamiento de los ecosistemas naturales, pero en décadas recientes han declinado en número y distribución por varios factores, entre los que destacan los antropogénicos. Por otro lado, la pérdida de conocimiento biocultural puede modificar la percepción que se tiene de estos organismos y llevar a una difícil coexistencia. Este trabajo tiene como objetivo caracterizar el conocimiento etnozoológico sobre la herpetofauna que tienen los pobladores de la comunidad maya de Santa Elena, Yucatán. De junio a octubre de 2016 se aplicaron 145 cuestionarios mixtos y dos entrevistas semiestructuradas a informantes clave. Como resultado sabemos que los habitantes de la comunidad maya de Santa Elena reconocen 68 especies (12 anfibios y 56 reptiles), de las cuales 31 son consideradas como venenosas. Se recopilaron 44 relatos, en los cuales la serpiente cascabel, en maya tsab kan (Crotalus tzabcan) fue la especie que obtuvo el mayor número de menciones (23%). De las especies registradas en el trabajo, 13 presentan algún tipo de uso. El medicinal fue el más mencionado para la serpiente cascabel (C. tzabcan) (53.1%) y la tortuga de caja, en maya, Xkok ak (Terrapene yucatana) (25.5%) y el uso alimenticio para la iguana, en maya tolok, C (Ctenosaura similis) (42%). Estos resultados reflejan la importancia de incluir el conocimiento local para mejorar las medidas de conservación de este grupo biológico.