Snakes of Colorado

Colorado has large areas of varied natural habitat which is suitable for an array of snake species. The state is home to 29 different species that range in size from a few inches to several feet in length. The majority of the state's native species are constrictors and are not considered dangerous to humans. Two of Colorado's species are venomous and may pose a risk, if encountered.

  1. Large Snakes

    • Colorado is home to five snake species which regularly grow over 4 feet in length. The largest is the gopher, or bull snake, which grows between 71 and 100 inches in length. The striped whip and great plains rat snakes are also large snakes, both growing to over 70 inches in length. The coachwhip snake can grow to 80 inches in length, but in Colorado it generally grows no longer than 59 inches. The common garter snake can grow to a little over 4 feet on average.

    Medium-Sized Snakes

    • Most of the state's native snakes grow to between 2 and 4 feet long, on average. The western ribbon, eastern hognose and glossy snakes all grow to around 4 feet in length. Six of the state's snakes reach around 3 feet including the northern water, rubber boa, racer, plains garter, common king and western hognose varieties. The smooth green snake, black-neck garter snake, long-nose snake and the milk snake all grow to over 2 feet in length.

    Small Snakes

    • Colorado is home to eight smaller species of snake that do not grow much over 2 feet in length. The smallest native species is the Texas blind snake which grows to around 11 inches in length. The southern black-headed snake is close in size at just about 12 inches in length. The plains black-headed, ring-neck, lined and brown snakes all grow to just over a foot in length. The ground snake and night snake both grow to an average of almost 2 feet in length.

    Venomous Snakes

    • The massasauga is one of Colorado's venomous varieties which grows to between 15 and 16 inches, on average, and is smaller there than in some other areas of its range. It is a thick-bodied snake with a small rattle and potentially deadly venom. The western rattlesnake is the state's other venomous snake. It grows to between 26 and 39 inches in length and has a thick body with a prominent rattle. Both species can be potentially deadly if bites are not treated.