Of the roughly 30 species of snakes in the state, only three are venomous and only one of those occurs throughout much of the state.
In Colorado, rattlesnakes may be legally killed if they pose a threat. All other snakes are classified as nongame wildlife and are protected by law, according to Colorado Parks and Wildlife.
Colorado is home to a diverse array of habitats, from alpine tundra to high-desert canyonlands This varied terrain supports around 30 different snake species, only three of which are venomous
In this article, we’ll explore everything you need to know about Colorado’s snakes, including:
- An overview of venomous and nonvenomous species
- Identification tips and facts about the most common snakes
- Safety precautions for avoiding bites
- How to peacefully coexist with these beneficial reptiles
Venomous Snakes in Colorado
Colorado has three venomous snake species:
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Prairie Rattlesnake – The most common and widespread rattlesnake. Populations statewide up to 9500 feet.
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Western Massasauga – Small rattlesnake limited to the southeast corner. Prefers dry grasslands.
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Midget Faded Rattlesnake – Tiny but highly venomous species only in west-central Colorado.
These pit vipers all have broad, triangular heads and rattles on the tip of their tails. Bites require immediate medical attention but are rarely fatal.
Venomous snakes are not aggressive and prefer to avoid humans. Most bites happen when people try to kill or handle the snakes.
How to Identify Colorado’s Snakes
Here are some key identification features for all snakes:
- Scales – Smooth or keeled (rough)
- Size – Length and girth
- Eyes – Round or elliptical pupils
- Pattern – Blotches, bands, stripes, or solid color
- Body Shape – Stocky or slender
- Head Shape – Round, triangular, pointed, or upturned snout
Many harmless species mimic venomous snakes, so positively identifying them can be tricky. When in doubt, treat them as potentially dangerous and keep your distance.
Most Common Nonvenomous Snakes
While Colorado has around 30 snake species, these five harmless snakes are encountered most frequently:
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Bullsnake – Heavy-bodied with yellow blotches. Up to 6 feet long. Found east of the Rockies.
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Gopher Snake – Lookalike species on the Western Slope. Excellent climber and burrower.
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Garter Snake – Slender with stripes. Mildly venomous but harmless to humans. Near water statewide.
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Coachwhip – Tan and long as 5 feet. The fastest snake in North America. Prefers the southeast.
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Western Terrestrial Garter Snake – Brown or gray with yellow stripes. Abundant below 9,500 feet.
Other Harmless Species to Know
Here are some additional nonvenomous snakes that call Colorado home:
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Rat Snakes – Agile climbers that eat rodents. Two species in Colorado.
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Racers – Speedy, nervous snakes that flee when approached. Two yellow-bellied species.
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Kingsnake – Immune to rattlesnake venom. Eats other snakes.
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Milk Snake – Constrictor with banded red, black and white pattern.
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Night Snake – Rear-fanged with mildly toxic saliva. Nocturnal.
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Ringneck Snake – Tiny reptile with bright yellow ring on its neck.
Snake Safety Tips
Follow these precautions to safely coexist with Colorado’s snakes:
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Leave snakes alone if encountered. Do not try to kill or harass them.
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When hiking, stick to designated trails and wear sturdy boots and long pants. Avoid reaching where you can’t see clearly.
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Supervise children and keep dogs leashed when exploring snake habitat like prairies and woodlands.
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Baby rattlesnakes can’t control their venom usage, making their bites more dangerous, so give all snakes extra space.
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If bitten, note the snake’s appearance if safely possible and seek immediate medical treatment.
Peacefully Coexisting with Snakes
Snakes play a valuable ecological role by controlling pest populations and as a food source for predators. By giving them space and respect, we can safely enjoy Colorado’s outdoor spaces together.
With knowledge and caution, harmful encounters can be avoided. Snakes only bite in self-defense as a last resort when threatened or harassed. Their intricate colors and behaviors are fascinating to observe from a distance.
So next time you see a snake slither by, appreciate its presence as an integral part of Colorado’s diverse ecosystems that are worth protecting.
Prairie rattlesnake is the most common venomous snake in Colorado
Here are facts about our venomous snakes, courtesy of the University of Colorado Museum of Natural History and other sources:
- Prairie rattlesnake: By far the most common venomous snake in the state. It can be found about anywhere below 9,000 feet but prefers rocky canyons in the foothills and the prairies. They eat small mammals, lizards, frogs, birds and insects. They typically are not aggressive and will usually only strike if threatened. They typically grow from 2 1/2 to 4 feet. To identify and what to do if bitten, read here.
- Western massasauga rattlesnake: Mostly found in the southeast quadrant of the state in dry, sandy soil. They eat rodents. Smaller than a prairie rattlesnake at 18 to 30 inches.
- Midget-faded rattlesnakes: Only found in far west-central Colorado. Smaller than prairie rattlesnakes, typically 2 feet long or less, but their venom is far more toxic than prairie rattlesnakes.
Prairie Rattlesnakes at a Mega-den in Colorado
FAQ
Are snakes a problem in Colorado?
Most Colorado snakes are nonvenomous (nonpoisonous), harmless and beneficial to people. Nonvenomous and venomous species can be easily distinguished from each other. Discourage snakes from entering buildings by sealing all holes in foundations. Reduce cover and food supplies to discourage them from living in backyards.
What months are snakes most active in Colorado?
When You Are Likely To Encounter Rattlesnakes. Rattlesnakes are active from early spring through mid fall. They hibernate in winter. Rattlesnakes are more active and more aggressive in spring, shortly after emerging from hibernation.
What part of Colorado has the most rattlesnakes?
- North Table Mountain Park. West trailhead in North Table Mountain Park with snow on the ground and a colorful sky. …
- Greater Fort Collins. …
- Garden of the Gods. …
- Ute Valley. …
- Rio Grande River.
Are there snakes in Colorado?
Yes, snakes can be found throughout Colorado. There are 28 different species of snakes in Colorado, with 3 of them being venomous.
What is the only abundant venomous snake in Colorado?
Only one of Colorado’s three venomous species is abundant throughout most of the state: the Prairie Rattlesnake. Texas Night Snakes still lack the heavy-bodied build, triangular head shape, and tail rattle of Colorado’s venomous snakes.
What does a venomous snake look like in Colorado?
All variations have dark blotches on the body that turn into rings near the tail. Broad triangular head, elliptical pupils, heat-sensing pits between the eyes and nostrils, and a tail rattle. These venomous snakes can be found in Colorado in open prairies, grasslands, semi-desert shrublands, and forested environments.
What is the largest snake in Colorado?
Bull snake or gopher snake: One of the most widespread and largest snakes in Colorado, growing up to 6 feet. They are often mistaken for rattlesnakes because of their appearance and behavior of rattling dry leaves or ground litter with their tale as a defense mechanism when threatened.
Are there garter snakes in Colorado?
There’s a diverse array of harmless snakes in Colorado, and almost all of them belong to the colubrid family of snakes. This Western Terrestrial Garter Snake is likely from the Southeastern region of Colorado because of its distinct dorsal stripe.
How do you know if a snake is in Colorado?
Look for a distinctive yellow or red neckband. The snake’s head color is usually slightly darker than the rest of the body, tending towards black rather than gray or olive. Adults are usually between 25-38 cm (10-15 in) long. It can be hard to find these snakes in Colorado!