Reptiles can cause fear or fascination in people. While many assume that desert dunes must contain snakes, there are actually no snakes living in the dunes themselves, and no venomous snakes have never been found in the park or preserve. Relatively few reptiles live in this high-elevation park.
While there are no rattlesnakes in Great Sand Dunes National Park and Preserve, they have been observed in some rocky canyons and foothills in the San Luis Valley. Rattlesnakes are infrequently observed along the foothills south of the national park.
Complete List of Reptiles, Amphibians, Fish, and Mammals of Great Sand Dunes National Park and Preserve (Revised 2015, .pdf file)