Grand Teton National Park is home to a diverse array of wildlife including several species of reptiles. Reptiles are a highly successful group of animals with dry, scaly skin that either lay eggs or bear live young. Although reptiles cannot maintain a constant body temperature like mammals, they can regulate their body temperature behaviorally, such as moving into or out of sunlight. The park's cold mountain climate limits the diversity, distribution, and abundance of reptile species found here. There are currently four confirmed species of reptiles in Grand Teton National Park. Along with one species of lizard, there are three species of snakes. The most common reptile in the park is the wandering garter snake (Thamnophis elegans vagrans).
The valley garter snake (Thamnophis sirtalis fitchi) and the rubber boa (Charina bottae) are much less commonly encountered. All three species of snakes typically live near areas of water. There are no species of poisonous snakes in the park. The only confirmed species of lizard in Grand Teton National Park is the northern sagebrush lizard (Sceloporus graciosus graciosus). Amazingly, this lizard species, which lives in dry, rocky sagebrush habitat, was not confirmed to exist within the 310,000-acre park until 1992. Although Grand Teton is a heavily visited jewel of the National Park Service, and much is known about its larger mammal species, this recent "discovery" points to our deficiency of knowledge of smaller invertebrate and vertebrate species within the park, including reptiles. Since the possibility exists that other reptile species, including the Great Basin gopher snake (Pituophis catenifer deserticola), may someday be found in the park, further study on the reptiles of Grand Teton National Park is needed.