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Geckos are among the most diverse radiations of lizards; however, the lack of baseline natural history data on the reproductive biology for many species creates a challenge for predicting their long-term persistence. This study aims to fill a gap in our understanding of the reproductive biology of an enigmatic nocturnal gecko endemic to the islands of Curacao and Bonaire: Gonatodes antillensis. Using radiographs of specimens from natural history collections, we conduct the first investigation of the potential role of endolymphatic sacs in the reproduction of the species. We find that females have larger endolymphatic sacs than males, with further quantification of endolymphatic sac sizes between females with or without visible eggs supporting the hypothesis that calcium stores are built up in the early reproductive phase and depleted during the development of the egg. Additionally, we combined data on endolymphatic sacs sizes with examinations of gravidity to expand the known reproductive interval of the species into fall and winter months and suggest the possibility of year-round reproduction. Along with providing baseline data, our findings raise a new conservation concern for the species. The spread of the invasive gecko Hemidactylus mabouia has resulted in a notable decline in the abundance of Gonatodes antillensis across its native range. This decline has been attributed to Hemidactylus mabouia acting as both a competitor and possible predator of Gonatodes antillensis. However, stress can inhibit calcium uptake in endolymphatic sacs, and these findings raise the possibility that Hemidactylus mabouia may also be indirectly affecting the reproductive success of this species.

Predicting the response of endemic species to urbanization has emerged as a fundamental challenge in 21st century conservation biology. The factors that underlie population declines of reptiles are particularly nebulous, as these are often the least understood class of vertebrates in a given community. In this study, we assess correlations between feeding ecology and phenotypic traits of the Lesser Antillean endemic Dutch leaf-toed gecko, Phyllodactylus martini, along an urban gradient in the Caribbean island of Curacao. There has been a marked decline of this species in developed habitats associated with the invasive tropical house gecko Hemidactylus mabouia. We find a correlation between aspects of locomotor morphology and prey in undeveloped habitats that is absent in developed habitats. Analyses of stomach contents further suggest that Phyllodactylus martini alters primary prey items in developed areas. However, changes in prey promote the overlap in foraging niches between Phyllodactylus martini and Hemidactylus mabouia, suggesting that direct resource competition is contributing to the decline of Phyllodactylus martini. In addition to competitive exclusion, we suggest that the urban extirpation of Phyllodactylus martini could also be attributed to a top-down control on population growth by Hemidactylus mabouia. Colonizations of walls put Phyllodactylus martini in direct contact with Hemidactylus mabouia increasing the chances for predation events, as evidenced by our observation of a predation event on a Phyllodactylus martini juvenile by an adult Hemidactylus mabuoia. In total, our results add to a growing body of literature demonstrating the threat that invasive synanthropic reptiles pose to endemics that might otherwise be able to cope with increased urbanization pressures.

In July 2012, 22 people representing eight institutions from six countries conducted a six-day expedition to the submontane heath forest near Bukit Pagon in Brunei Darussalam. Base camp was located at an elevation of 862 masl about 200 m from the Brunei-Sarawak border and 9 km from the peak of Bukit Pagon. The herpetology and ichthyology portion of the survey resulted in the collection of 61 specimens, representing 30 species, with 4 additional species documented by photograph but not collected. One additional taxon, Tropidophorus brookei, was seen but neither collected nor photographed. Nearly half of the species found are endemic to Borneo. The findings of this brief expedition shed light on the distribution of many endemic taxa in one of the world's greatest biodiversity hot spots. Despite its small size, Brunei supports a rich vertebrate fauna that is understudied compared with neighboring Sarawak and nearby Sabah.

Instances of vertebrates supplementing their diets through the ingestion of gastroliths have been observed or documented in numerous organisms, including birds, crocodiles and dinosaurs. Although not uncommon, this behavior can be motivated by a wide range of factors that include endoparasite removal, stomach cleaning, or calcium supplementation during eggshell formation. As plant-based diets are often mineral deficient, the use of gastroliths as calcium supplements may play an important role in the reproductive biology of egg-laying herbivorous reptiles. Whereas gravid females of some species of herbivorous reptiles have been shown to seek out calcareous gastroliths, the occurrence or prevalence of gastroliths in gravid females remains unknown for many species. Using field observations and radiographs, we studied patterns of gastrolith ingestion by adult female gopher tortoises (Gopherus polyphemus), a herbivorous species of testudinoid turtles. Gastroliths documented included fossil seashells, calcareous stones and carnivore feces containing vertebrate bones. The prevalence of gastroliths was significantly different between gravid and non-gravid tortoises. We suggest this behavior is a means of supplementing calcium intake during eggshell formation and may play a part in the female reproductive biology of this species.

It is well known that reptiles can act as paratenic hosts for parasites that use mammals as their definitive hosts. However, studies of potential paratenic hosts in the Caribbean have been temporally restricted to only diurnal species of lizards, thereby neglecting a dominant component of the nocturnal reptilian community: geckos. Many gecko species are human commensals with activity periods that overlap temporally with those of domestic cats, making them prime candidates as potential transport hosts for cat parasites. However, no studies have reported geckos as paratenic hosts for felid parasites on any Caribbean island. Here we report the first records of subcutaneous oligacanthorhynchid cystacanths on the Venezuelan Coastal Clawed Gecko (Gonatodes antillensis) based on specimens collected in Curacao and Bonaire. The cysts were identified as belonging to the genus Oncicola, likely those of Oncicola venezuelensis. This study reports these geckos as a new host record for oligacanthorhynchid cystacanths, as well as Curacao and Bonaire as new geographic locales for these acanthocephalan parasites. We additionally provide a review of saurian cystacanths, comparing the restricted taxonomic focus of transport hosts in Caribbean islands to the distribution of paratenic squamate hosts both in the Neotropics and globally. We find evidence that the ability of squamate reptiles to act as transport hosts is a pervasive feature across their Tree of Life, suggesting that these animals may serve as important vectors for transporting parasites between intermediate and definitive hosts.

Despite increasing popularity of the island as an ecotourist destination, the ecology and natural history of many organisms native to the Lesser Antillean island of Curacao have remained enigmatic. We document multiple new observations of the behavioral ecology of several terrestrial and aquatic vertebrates that inhabit Curacao. We present the first report of avian predation on the endemic Curacao whiptail lizard, Cnemidophorus murinus, suggesting these lizards play a potentially important role in this island’s food web. We also document the first instance of predation by the introduced tropical house gecko, Hemidactylus mabouia, on the native Antilles gecko, Gonatodes antillensis. Tropical house geckos are thought to be displacing native geckos through a combination of niche displacement and competitive exclusion, and our finding suggests that predation on smaller native lizards may be another factor aiding the success of this introduced gecko on Curacao. We also present repeated observational evidence that juvenile bluehead wrasses (Thalassoma bifasciatum) seek refuge among the sessile and venomous giant Caribbean sea anemones (Condylactis gigantean).

The Yale University Prehistoric Expedition to Nubia collected zoological specimens and archeological artifacts from Egypt and the surrounding region from 1962 to 1965. A total of 2486 herpetological specimens were collected during this time, representing 51 species and 13 families. Among the herpetological specimens is a series of 1232 Chalcides ocellatus and a recently described species of spitting cobra (Naja nubiae). Because most of the collection sites are now under Lake Nasser, most specimens represent extirpated populations. Some specimens are of taxa now considered endangered species in Egypt. Although the primary purpose of the YUPEN expedition was to preserve the rich anthropological history south of Aswan, the herpetological specimens that were preserved provide a valuable temporal snapshot into the historical ecosystems that were present in Lower Egypt.

Despite more than 150 years of research, to date a concise summary of the spatial distribution of Connecticut's freshwater fish fauna is lacking. Here we compile the spatial data assigned to more than a century's worth of collection efforts. Our survey summarizes specimen data previously deposited within 10 museums, comprising a total of 1305 specimen lots for 84 species. We assigned each lot to the township where it was collected, the first detailed summary of the distribution of Connecticut's freshwater fishes, with the ultimate goal of providing a framework for further local studies of freshwater fish conservation biology, ecology, evolution and management. Our records also reveal several populations not yet documented, including previously overlooked stickleback records that could have broader evolutionary implications.

Zoological collections housing Egyptian specimens that pre-date the construction of the Aswan High Dam are of unique historical importance. Before the construction of the High Aswan Dam, Yale University organized three archeological salvage expeditions, between 1962 and 1965, to the Nile River Valley south of Aswan as part of an international UNESCO-organized salvage mission. Although the focus of these expeditions was the recovery of archeological artifacts, team leaders also included collection of zoological specimens in their operations. These efforts resulted in the collection of 448 species spanning 16 families of Egyptian mammals that were subsequently deposited in the Yale Peabody Museum of Natural History. Our re-survey of these collections revealed that almost two-thirds had been misidentified or only identified to “order” level taxonomic ranks. Many of the specimens collected were from sites now submerged beneath Lake Nasser and so provide a unique temporal snapshot of a region whose bi...