Discover the 2 Types of Rattlesnakes in Wyoming

rattlesnakes in Wyoming

Written by Kellianne Matthews

Updated: February 9, 2023

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Key Points:
  • The prairie rattlesnake is the only venomous snake residing in Yellowstone National Park. Its venom is deadly, a mixture of hemotoxins and neurotoxins.
  • Midget faded rattlesnakes, which only grow to about 25 inches in length, have an extremely toxic neurotoxic-myotoxic venom. Studies suggest that their venom is as toxic as a cobra.
  • Twelve other varieties of snakes reside in Wyoming, all non-venomous. Some include garter snakes, rubber boas, racer snakes, hognose snakes, and whip snakes.

Wyoming is home to at least 14 different species of snakes. However, of all the snakes in Wyoming, only two types are considered dangerous: the prairie rattlesnake and the midget faded rattlesnake. Let’s take a closer look at the two types of rattlesnakes in Wyoming.

1.      Prairie Rattlesnake

Prairie rattlesnakes spend most of their time slithering on the ground but they can also climb trees, navigate bushes, and are known to hide in rock crevices or small caves.

©Harris Motion Photo/

Prairie Rattlesnake
RangeAll of Wyoming, but most common in northwest Wyoming
Length34-45 inches

The Prairie Rattlesnake lives throughout most of Wyoming but is most common in the northwestern portions of the state. In fact, it is the only venomous snake found in Yellowstone National Park, usually in the lower regions of the park.

Prairie rattlesnakes are usually light brown, greenish-brown, greenish gray, or yellow, with white-bordered dark brown blotches along their backs to help them blend in with the prairie landscape. These snakes look like they have a texture. This is because their scales are keeled, with a ridge running down each scale. In Wyoming, these snakes can be more than 48 inches long.

Although it looks intimidating, the prairie rattlesnake is not very aggressive. It will defend itself if provoked, but generally, it attempts to avoid humans and other large animals. There have been only two recorded cases of a prairie rattlesnake bite in Yellowstone. The venom of prairie rattlesnakes is quite potent, a mix of hemotoxins and some neurotoxins. These snakes primarily eat small mammals, but have been known to hunt small reptiles and amphibians as well.

2.      Midget Faded Rattlesnake (Western Rattlesnake)

The Midget Faded Rattlesnake’s venom is one of the most potent in North America.

©Rusty Dodson/

Midget Faded Rattlesnake
RangeSouthern Wyoming
Length25 inches or less

The Midget Faded Rattlesnake is a subspecies of western rattlesnake that lives in southern Wyoming in rocky areas south of the Seedskadee National Wildlife Refuge. This snake is protected by Wyoming state laws.

This is a smaller rattlesnake, growing to be no more than 25 inches long, with a cream, yellow-brown, or light pinkish-brown body. Midget faded rattlesnakes have darkly outlined rectangular patterns along the length of their bodies. Younger snakes have bolder colors and more distinct patterns that fade as they get older. Older snakes can be hard to find, blending seamlessly into their rocky habitats with ease.

Midget faded rattlesnakes have an extremely toxic neurotoxic-myotoxic venom. Studies suggest that their venom is as toxic as a cobras is—it might even be more potent than cobra venom in some cases. Generally, these snakes eat cold-blooded animals like lizards.

Other Snakes in Wyoming

In addition to the prairie rattlesnake and the midget faded rattlesnake, there are at least 12 other kinds of non-venomous snakes that live in Wyoming. Take a look at just a few different types of Wyoming’s nonvenomous snakes.

Garter Snakes

common garter snake slithering in grass

All garter snakes have keeled scales, which means they have a ridge down the center.


Garter Snake
RangeAll of Wyoming
Length18-54 inches

Garter snakes are one of the most common types of snakes living in Wyoming. There are several different types of garter snakes found in Wyoming, like the wandering garter snake, common garter snake, red-sided garter snake, and plains garter snake. Garter snakes are harmless and come in a variety of different colors, often with long vertical stripes. These snakes are very adaptable but usually live near a water source. If a garter snake feels threatened, it will usually flail its tail, try to hide its head., or release a musk. Garter snakes are excellent pest controllers, eating insects, spiders, amphibians, slugs, and leeches.

Northern Rubber Boa

Rubber Boa

Rubber Boas are very docile snakes.

©Matt Jeppson/

Northern Rubber Boa
RangeThe northwestern corner of Wyoming
Length14-33 inches

The Northern Rubber Boa lives in the northwestern corner of Wyoming. This snake has a rather thick body that looks like rubber, covered in tiny scales. Northern rubber boas are secretive, non-aggressive snakes and only come out at night every few days. These snakes can climb, burrow, and swim. They eat small mammals, birds, lizards, reptile eggs, and salamanders.

North American or Eastern Racer

Snakes in Kansas - Eastern Racer Snake

The Eastern Racer gets its name because it is very fast and looks like it is racing.

©Matt Jeppson/

North American or Eastern Racer
RangeAll of Wyoming
Length36-60 inches

The North American or eastern racer is one of the most common types of snakes living in Wyoming. This snake is 36-60 inches long and is usually greenish-gray, blue, or brown in color. Its scales are very smooth, and it has a pale yellow belly. Eastern racer snakes’ eyes are quite large, although their heads are relatively small. The racer is non-venomous, but it is fast and very active (which is why it is called a “racer”). In fact, its been known to reach up to 4 miles an hour in speed.

North American and Eastern racer snakes are constrictors, but they don’t typically squeeze their prey to death, opting instead to overpower and mash the prey with their coils until it succumbs or dies. They are also great tree climbers and often feast on avian prey and their eggs.

Western Hognose Snake

The Western Hognose Snake has a thick body and is slightly smaller than the Eastern Hognose.

The Western Hognose Snake has a thick body and is slightly smaller than the Eastern Hognose.

© Morozova

Western Hognose Snake
RangeEastern Wyoming
Length15-20 inches

The Western Hognose Snake gets its name from its hog-like nose. The snake uses this upturned snout like a small shovel to burrow into the ground. Western hognose snakes are smaller, measuring between 15-20 inches long. People often mistake these snakes for rattlesnakes when seen from a distance, but the Western hognose snake does not have venom and is not dangerous. In fact, you can find these snakes in pet stores throughout the United States. Western hognose snakes come in many different colors. Commonly they are olive green or gray-brown with darker spots along their backs.

Desert Striped Whipsnake

Desert Striped Whipsnake

The Desert Striped Whipsnake lives in the western United States and northern Mexico.

©Randy Bjorklund/

Desert Striped Whipsnake
RangeSouthwestern Wyoming
Length30-72 inches

The Desert Striped Whipsnake lives in southwestern Wyoming near the southern part of Flaming Gorge. These snakes are 3-6 feet long with thin, whip-like bodies. Desert stiped whip snakes are usually black, dark brown, or gray with a blue or green colored sheen. They have light stripes with intersecting black lines patterned along their bodies. Desert striped whip snakes are savvy hunters that can quickly slip into cracks and holes and even climb trees.

How to Identify a Rattlesnake

Rattlesnakes can be identified by their triangular head shape and vertical pupil in the eye. They also have a rattle at the end of their tail that they use to make noise when threatened. You will often hear them long before you see them, so it is important to keep your ears open when hiking around Wyoming.

Other identifying features include heat-sensing pits between the eyes and nostrils, keeled scales (scales with a raised ridge down the center), and an overall pattern that consists of large blotches or bands on their back. In Wyoming, rattlesnakes are typically gray or yellowish-brown with wide black or dark brown blotches along its body. It’s important to note that not all rattlesnakes look identical. Some may have different colors, patterns, and sizes depending on location and species.

Rattlesnake Tail

Rattlesnakes are easy to identify by the rattle at the end of their tail. Listen carefully when hiking and you may hear it.

©Chase D’animulls/

Other Wildlife

Wyoming is home to some of the most beautiful and diverse wildlife in the United States. Visitors can expect to see elk, mule deer, pronghorn antelope, bison, moose, coyotes, wolves, black bears, and grizzly bears throughout the state. Up in Yellowstone National Park, you may even spot a mountain lion or two.

Wyoming also has many species of birds. The greatest diversity of birds can be found during migration when hawks soar overhead on their way south for winter while songbirds flit from bush to tree, singing up a chorus of calls. Whether it’s exploring high alpine meadows in search of wildflowers or just getting lost amongst herds of buffalo along rolling plains, witness firsthand why people come from all around the world just to experience Wyoming’s natural beauty!

American bison in the middle of the road
Wyoming is home to many amazing wild animals.

Summary of 2 Rattlesnakes and Some Others in Wyoming

1Prairie RattlesnakeX
2Midget Faded RattlesnakeX
3Garter Snake
4Northern Rubber Boa
5North American or Eastern Racer
6Western Hognose Snake
7Desert Striped Whipsnake

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About the Author

Kellianne Matthews is a writer at A-Z Animals where her primary focus is on anthrozoology, conservation, human-animal relationships, and animal behavior. Kellianne has been writing and researching animals for over ten years and has decades of hands-on experience working with a variety of different animals. She holds a Master’s Degree from Brigham Young University, which she earned in 2017. A resident of Utah, Kellianne enjoys creating, exploring and learning new things, analyzing movies, caring for animals, and playing with her cats.

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