Coleman M. Sheehy III

• PhD
• Manager at Florida Museum of Natural History

We quantified drinking behavior in three species of North American watersnakes: Nerodia clarkii , which is a marine or brackish water amphibious species, and Nerodia fasciata and Nerodia taxispilota , both freshwater amphibious species. All three species have relatively small and similar thresholds of dehydration (TH, approximately −4% loss of body...

The complex and successful evolutionary history of snakes produced variation in the position and structure of internal organs. Gravity strongly influences hemodynamics, and the impact on structure and function of the cardiovascular system, including pulmonary circulation, is well established. Therefore, we hypothesized that interspecific variation...

Acquisition of fresh water (FW) is problematic for FW-dependent animals living in marine environments that are distant from sources of FW associated with land. Knowledge of how marine vertebrates respond to oceanic rainfall, and indeed the drinking responses of vertebrates generally following drought, is extremely scant. The Yellow-bellied Sea Snak...

Marine snakes represent the most speciose group of marine reptiles and are a significant component of reef and coastal ecosystems in tropical oceans. Research on this group has historically been challenging due to the difficulty in capturing, handling, and keeping these animals for field- and lab-based research. Inexplicable declines in marine snak...

The Yellow‐bellied sea snake ( Hydrophis platurus ) is the only pelagic species of marine snake and ranges from southern Africa across the Indo‐Pacific to the Pacific coast of Central America. It is subject to long‐range movements by drifting with gyres and currents, and it is the only species of sea snake to have reached the Americas. Like other s...

Roughly 70 species of sea snakes inhabit the Indo-Pacific but are absent from the Atlantic Ocean. Paleoclimatic conditions in the Coral Triangle were favorable for evolutionary transitions to the sea, while those in the Caribbean region and coastlines bordering the Atlantic Ocean were less favorable. The dispersal of sea snakes from the Indian to A...

The pelagic sea snake, Hydrophis (Pelamis) platurus is the only truly pelagic species to traverse both the Indian and Pacific oceans. Despite this extensive distribution, little is known about the interconnectivity between populations. We are gathering tissue samples for DNA analyses (ddRADseq) to conduct population genetic analyses in this species...

Observations of Florida Cottonmouth snakes (Agkistrodon conanti) at Seahorse Key, Florida, USA, provide strong evidence for synchrony of ecdysis among individuals of this insular population which live in relatively close social contact. Laboratory observations suggest that these and other snakes may also synchronize shedding cycles when individuals...

Gravity imposes potentially significant constraints on blood circulation in tall or elongate animals during upright posture or climbing. Intravascular pressures increase in the lower limbs or body during upright posture in tall and erect animals, which potentially reduces blood flow to the head because of edema and pooling of blood in dependent, di...

We quantified the abundance of pelagic sea snakes, Hydrophis (= Pelamis) platurus, while following slicks that formed drift lines during 3 yr of research in the Golfo de Papagayo, Costa Rica. The number of snakes we observed floating on slicks varied greatly and ranged from 0 to 1,029 per hour. The largest number we observed was highly unusual in r...

Cottonmouth snakes residing on certain Gulf coastal islands of Florida feed largely by scavenging fish that are dropped or regurgitated by colonial nesting birds. Because of the relative isolation of these snakes and their long association with bird rookeries, it is of interest to inquire whether snakes exhibit any dietary preference, or whether co...

Gravity imposes potentially important constraints on blood circulation in tall or elongate animals during upright posture or climbing. Upright postures create vertical gradients of gravitational (=hydrostatic) pressures within circulatory vessels. In terrestrial animals, this pressure potentially induces blood pooling and oedema in dependent (infer...

Water is an essential resource affecting behavior and the acquisition of energy, especially in environments where water is spatially or temporally restricted or unavailable. Recent investigations have shown that several species of marine snakes dehydrate at sea and are dependent on environmental sources of fresh water to maintain water balance. How...

Range expansion for Anolis sagrei.

We describe a new species of Siphlophis from the Amazonian slopes of the Ecuadorian Andes, in the provinces of Azuay, Tungurahua, and Zamora Chinchipe. This is the third species of Siphlophis known from Ecuador and the seventh species in the genus. The new species of Siphlophis is distinguished from all other Siphlophis by characters of external mo...

Gravity imposes potentially important constraints on blood circulation in elongate animals during upright posture or climbing. We test the hypothesis that arboreal snakes have longer tails than non-scansorial species and interpret the results in context of adaptation to gravity stress. Length data for 226 species in 15 snake families were divided a...

Gravity imposes potentially important constraints on blood circulation in elongate animals during upright posture or climbing. We test the hypothesis that arboreal snakes have longer tails than non‐scansorial species and interpret the results in context of adaptation to gravity stress. Length data for 226 species in 15 snake families were divided a...

Secondarily marine vertebrates are thought to live independently of fresh water. However, some species of sea snakes require sources of fresh water even though they possess extrarenal salt glands. Here we tested the hypothesis, and demonstrate, that the only pelagic sea snake, Pelamis platurus , dehydrates at sea and spends a significant part of it...

Secondarily marine vertebrates are thought to live independently of fresh water. Here, we demonstrate a paradigm shift for the widely distributed pelagic sea snake, Hydrophis (Pelamis) platurus, which dehydrates at sea and spends a significant part of its life in a dehydrated state corresponding to seasonal drought. Snakes that are captured followi...

Dehydration and drinking behaviors were investigated in the little file snake (Acrochordus granulatus) collected from marine populations in the Philippines and in Australia. File snakes dehydrate in seawater and do not drink seawater when dehydrated in air and offered seawater to drink. Dehydrated file snakes drink freshwater, and the threshold of...

Secondarily marine vertebrates are thought to live independently of fresh water. Here, we demonstrate a paradigm shift for the widely distributed pelagic sea snake, Hydrophis (Pelamis) platurus, which dehydrates at sea and spends a significant part of its life in a dehydrated state corresponding to seasonal drought. Snakes that are captured followi...

The Indonesian parachuting frog Rhacophorus catamitus is endemic to the mountains of southern Sumatra. Herein, we describe the larval morphology of this species based on several developmental stages. Tadpoles were collected from localities that ranged in elevation from 1,068-1,680 m in montane primary and secondary growth rainforest habitats. We ma...

The Chiricahua Leopard Frog (Lithobates chiricahuensis) occurs in parts of the southwestern United States and northwestern Mexico. In the United States, it is listed as a federally threatened species. Although extensive research has been conducted on populations in the United States, the status of most Mexican populations is unknown. We used mitoch...

The yellow-bellied sea snake, Pelamis platurus (Elapidae, Hydrophiinae), has the largest distribution of any snake species, and patterns related to its distribution and regional color variation suggest there is population structuring in this species. Here, we use mitochondrial (ND4, Cyt-b) and nuclear (RAG-1) DNA to (1) test whether genetic variati...

The Trans-Mexican Volcanic Belt and surrounding areas contain substantial biological diversity. The mountains that make up the Trans-Mexican Volcanic Belt are a hypothesized biogeographic barrier for the terrestrial fauna found in the region. Several phylogeographic studies have provided genetic evidence in support of this historical narrative; how...

Recent investigations of water balance in sea snakes demonstrated that amphibious sea kraits (Laticauda spp.) dehydrate in seawater and require fresh water to restore deficits in body water. Here, we report similar findings for Pelamis platurus, a viviparous, pelagic, entirely marine species of hydrophiine (“true”) sea snake. We sampled snakes at G...

Under circumstances in which area for settlement is limited, the colonization of living substrata may become a highly valuable strategy for survival of marine invertebrates. This phenomenon, termed epibiosis, results in spatially close associations between two or more living organisms. Pelamis platurus, the yellow-bellied sea snake, is the only exc...

The Yellow-bellied sea snake, Pelamis platurus, inhabits warm tropical waters of the Pacific and Indian Oceans and is the only extant sea snake species to have colonized the New World. At present, intraspecific patterns of genetic diversity are unknown in these snakes. Although this species is morphologically conserved, two distinctly different col...

Physiological investigations of snakes have established the importance of heart position and pulmonary structure in contexts of gravity effects on blood circulation. Here we investigate morphological correlates of cardiopulmonary physiology in contexts related to ecology, behavior and evolution. We analyze data for heart position and length of vasc...

Evolutionary transitions between different environmental media such as air and water pose special problems with respect to skin permeability because of the dramatic changes in the driving gradients and nature of water exchange processes. Also, during the transitional periods prior to complete adaptation to a new medium, the skin is exposed to two v...

It is difficult for terrestrial vertebrates to invade the sea, and little is known about the transitional evolutionary processes that produce secondarily marine animals. The utilization of marine resources in the intertidal zone is likely to be an important first step for invasion. An example of this step is marine scavenging by the Florida cottonm...

Dehydration and procurement of water are key problems for vertebrates that have secondarily invaded marine environments. Sea snakes and other marine reptiles are thought to remain in water balance without consuming freshwater, owing to the ability of extrarenal salt glands to excrete excess salts obtained either from prey or from drinking seawater...

We studied transepithelial evaporative water loss (TEWL) and skin resistance (R s ) in three species of sea kraits differing in both terrestrial tendency and water permeability of skin. Laticauda colubrina is semi‐terrestrial and its mean TEWL is 0.118 ± 0.11 mg cm ⁻² h ⁻¹ ; L. laticaudata is relatively more aquatic and TEWL = 0.37 ± 0.20 mg cm ⁻²...

Florida cottonmouth snakes (Agkistrodon piscivorus conanti) exhibit significant variation of foraging behavior on a single island at Cedar Keys, Florida. Snakes in this population characteristically remain beneath avian rookeries where colonial nesting birds drop or regurgitate fish that are consumed (by snakes) as carrion. Observations and studies...

We describe a new species of Ischnocnema from upper montane rainforest in La Paz, Bolivia. Unlike its congeners, the new species possesses notched ungual flaps, a short dorsolateral fold, and a small axillary gland. The new species resembles I. sanctaecrucis and is the third species of Ischnocnema known from Bolivia. UNTIL the 1970's, the genus Isc...

A recent field survey in the Florida Keys, Monroe County, resulted in much noteworthy herpetological information. We confirm the exist-ence of the ocellated gecko (Sphaerodactylus argus argus) on Stock Island and Key West, a species that had not been found in 26 years. Additionally, we report range expansion in the common (Hemidacty-lus frenatus) a...

Abstract: During recent surveys between March and August 2002, we found established populations of the Madagascar giant day gecko (Phelsuma madagascariensis grandis) in the Florida Keys, Monroe County. We recorded 29 individuals on Little Torch Key and three individuals on Grassy Key. Additional records were obtained from Grassy Key, Big Pine Key,...

Florida is well known for its non–native herpetofauna (King and Krakauer 1966; Wilson and Porras 1983). The substantial trade in exotic plants and animals and the humid subtropical environment in Florida have been instrumental in perpetuating populations of exotics. From May 2000 through March 2001 we surveyed areas in Florida where introduced spec...