Yellowstone National Park attracts millions of visitors each year with its stunning natural wonders including dramatic landscapes like the Grand Canyon of the Yellowstone and unique hydrothermal features. For many, the park’s greatest appeal lies in the chance to observe wildlife in a largely intact ecosystem.
Yellowstone National Park is home to the largest bison population on public land in the United States. It is the only place in the country where bison have lived continuously since prehistoric times, with thousands roaming freely across the park’s vast landscapes. The bison population in Yellowstone fluctuates from 3,500 to nearly 6,000 animals including two primary breeding herds.
American bison are the largest land mammals in North America with males reaching up to 2,000 pounds. They all have a protruding shoulder hump and large shoulder and neck muscles, allowing them to use their heads to clear snow from foraging patches. A full grown male bison can stand around 6 feet tall, as shown in the following video where the animal stands next to a full-size pickup truck.
The truck in video appears to be a Ford F-150, specifically a 12th generation. Depending on the year and model, those trucks typically ran no shorter than ~6.2 feet. It may be a bit of forced perspective, but that bison sure seems to stand near or at the same height as the truck.
Despite their impressive size, bison can be quick and agile. They’ve injured more people in Yellowstone National Park than any other animal and must be given at least 25 yards of space at all times. Read more on bison safety in Yellowstone National Park below.
Yellowstone National Park Bison Safety:
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.
