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Most Dangerous Animals in Wyoming

Home to Yellowstone National Park, the Grand Tetons, and Jackson Hole, the state of Wyoming is a prime destination for hikers, bikers, hunters, skiers, and outdoor enthusiasts from all walks of life. With its pristine landscapes and millions of acres of public land, however, comes an abundance of wildlife.
Wild animal attacks on humans are quite rare, but that doesn’t mean we should ever take safety for granted when recreating outdoors. We’ll cover some of the most dangerous Wyoming animals and how to stay safe when encountering them.

Grizzly Bear

The Rocky Mountain range is home to both black bears and grizzly bears. While both species can attack humans, grizzlies are larger and generally more dangerous. Grizzlies are powerful predators with the potential for aggression, especially when surprised or protecting their cubs.
When recreating in bear country, make noise as you move about to alert bears to your presence. It’s a good idea to carry bear spray just in case. If you do encounter a bear, stay at a safe distance. In the rare event of a bear attack, play dead and protect your neck and stomach.


There are several species of venomous snakes in Wyoming, including two types of rattlesnakes.
The prairie rattlesnake is most commonly found in northwest Wyoming and can grow to lengths of up to five feet. The endangered midget faded rattlesnake, on the other hand, can only be found in the southwestern corner of the state. 
Both types of rattlesnakes are venomous, and their bites can cause pain, swelling, and potentially serious health complications. These snakes will generally only attack if provoked or threatened, so the best way to avoid danger is to stay aware while in their habitat.
Stay on well-trodden paths, wear sturdy boots, and be cautious when stepping over rocks or logs. If you see or hear a rattlesnake, give it plenty of space. Do not attempt to touch, hurt, or kill the snake. If bitten, seek immediate medical attention.

Mountain Lion

Mountain lions, also called cougars, inhabit Wyoming‘s mountains and foothills. They generally avoid humans, although habitat encroachment has led to increased contact with the big cats in recent decades. 
If you live near a mountainous area of the state, keep mountain lions away by securing pets and livestock, especially at night. If a cougar cannot find food, water, or shelter on your property, they will move on.
Stay safe while hiking by traveling in a group when in areas frequented by mountain lions. Just like with bears, make noise to announce your presence. Most of the time, this will be enough to  keep the cat out of your path.
If you encounter a mountain lion, do not run away or turn your back on the animal. Maintain eye contact while slowly backing away. If attacked, fight back, especially if you can get ahold of rocks, sticks, or other large or heavy objects.


While moose may seem docile, they are among the largest and most powerful mammals in North America. If a moose feels threatened or is with its calves, it may become aggressive toward humans and other animals.
Moose can weigh more than 1,000 pounds and stand taller than many adult humans. They can run very quickly and may charge if provoked. Never approach a moose and do not allow your dogs to do so either.
During late September and October, bull moose may be aggressive toward humans, as this is their mating season. In the late spring and early summer, cow moose may have calves with them and will attack to protect their young. If a moose displays aggressive behavior, back away slowly and avoid direct eye contact.
A herd of Bison overlooking a river valley.


The American Bison, more commonly called buffalo, roam freely in Wyoming‘s national parks and grasslands. Despite their seemingly placid demeanor, bison can be unpredictable and charge when they feel threatened. 
Occasionally, tourists visiting one of the Cowboy state’s national or state parks will underestimate the potential danger of Wyoming wildlife. One woman was attacked in 2020 while attempting to take a selfie with a buffalo.
Maintain a safe distance—the National Park Service recommends at least 25 yards between you and the nearest buffalo. If one approaches you, back away slowly and find shelter.

Gray Wolf

The wolf was reintroduced to the Greater Yellowstone Ecosystem in the late ‘90s. Like most other wildlife, wolves are not generally a danger to humans—they will avoid you if they can. Yellowstone wolves have never caused a human fatality.
Wolves may, however, try to kill livestock or pets if they cannot find other prey. They can also become habituated to people, making them more likely to cause harm. 
A wolf can run up to 37 miles per hour at top speed. Single wolves have been known to kill larger prey such as bison using their sharp teeth and powerful jaws.
If you see a wolf, maintain at least 100 yards of distance. Always keep your dog on leash, especially in national parks.
If the wolf is getting too close and does not appear to be scared, do not run. If a wolf approaches you, make yourself as large and loud as possible—yell, wave your arms, and open your jacket. You may need to use your bear spray if all else fails. 


Dogs are obviously not categorized as wildlife, but they are responsible for more human injuries and deaths than many types of wild animals. This is mainly due to the fact that they are far more likely to interact with humans than other animals.
You should never approach a strange dog without its owner’s consent first. Some dogs are wary of strangers and will snap if they feel threatened. Always keep your own dog on leash when away from your private property or designated public off-leash areas.
Do not run from a dog that appears dangerous. This could cause the dog to chase you. Instead, stand tall and avoid eye contact. Back away slowly and use a calm but firm voice to try giving the dog commands (such as “sit,” or “no,”). 
If you are bitten by another person’s dog, seek medical attention and report the bite to animal control. The dog owner’s homeowners’ insurance may cover your medical expenses. Consider contacting a personal injury attorney with The Advocates to explore your legal options for financial recovery.