As highly adaptable omnivores the grizzly bears of Yellowstone National Park have a diverse diet ranging from succulent grasses and dandelions to ants and spawning cutthroat trout but from March through May, ungulates (mostly elk and bison) comprise a substantial portion of a grizzly bear’s calorie intake.
Bison are the largest land mammal in North America with bulls weighing up to 2,000 pounds and standing 6 feet tall and are a formidable and dangerous prey for a solitary grizzly bear. When grizzlies do hunt bison they usually target weakened or vulnerable individuals like those suffering from injury or young calves.
When a grizzly is faced with a full grown bison it is far from a forgone conclusion that the apex predator will have the upper hand in the exchange. Take for example this interaction in Yellowstone’s Lamar Valley where a grizzly bear is forced to flee from a charging bison.
While grizzly bears are natural predators of bison, they will often back down in the face of charging adult bison rather than risking injury. The wildlife observation opportunities at Yellowstone are unparalleled but its important to remember to stay safe in the presence of its majestic animals. The primary rule to keep tourists safe is always staying at least 100 yards away from bears and wolves and at least 25 yards away from all other animals, including bison and elk. Learn more about wildlife safety at Yellowstone below.
Yellowstone National Park Bear Safety Guidelines:
All of Yellowstone is bear country, from the trails in the park’s backcountry to the boardwalks and parking lots around Old Faithful. Your safety cannot be guaranteed, but you can play an active role in protecting yourself and the bears people come here to enjoy.
- Give bears space. Keep at least 100 yards (93 meters) from bears at all times and never approach a bear to take a photo.
- Carry bear spray and know how to use it. We recommend each person carry one can of bear spray in a readily accessible location like a quick-draw holster (not stowed away in your backpack).
- Hike in groups and make noise. Since 1970,91% of the people injured by bears in Yellowstone were hiking alone or with only one hiking partner. Only 9% of the people injured by bears were in groups of three or more people. While hiking on a trail, periodically yell “Hey bear!” to alert bears of your presence. Learn more about backcountry safety.
- Respect closures. Observe all closures and restrictions in active bear management areas.
- Never feed bears. Bears that become dependent on human food may become aggressive toward people and will be killed.
- Stay with your stuff. Do not leave packs or bags containing food unattended, even for a few minutes, as bears learn new food sources quickly.
- If a bear approaches or touches your car, honk your horn and drive away. We want to discourage this behavior for the bears’ safety and yours.
- Help us spread the word! Share posters from our “A Bear Doesn’t Care” campaign.
Yellowstone National Park Bison Safety Guidelines:
Bison have injured more people in Yellowstone than any other animal. Bison are unpredictable and can run three times faster than humans. Always stay at least 25 yards (23 m) away from bison.
- Give bison space when they are near a campsite, trail, boardwalk, parking lot, or in a developed area. If need be, turn around and go the other way to avoid interacting with a wild animal in close proximity.
- Approaching bison threatens them, and they may respond by bluff charging, head bobbing, pawing, bellowing, or snorting. These are warning signs that you are too close and that a charge is imminent.
- Do not stand your ground. Immediately walk or run away from the animal. Spray bear spray as you are moving away if the animal follows you.
