Bison in Winter
I am always amazed when I watch and photograph bison in Yellowstone National Park in the winter. They seem docile, slow moving, peaceful, unconcerned and focused on foraging. But we are not fooled – they are the most dangerous animal in the park. The bison’s temperament is often unpredictable, attacking without warning and can run at speeds up to 35 miles per hour. In Yellowstone, five times as many people are killed by bison than by bears every year.
Winter is particularly difficult for bison. On average, 9 out of 100 adult bison will die during the winter. Generally these animals entered winter in poor condition due to age, disease, or injuries. Young bison entering their first winter face a higher risk of dying: 20 to 40 of every 100 first-year animals may die from accidents, winter exposure, or predation.
Bison are vegetarians and feed on grasses and sedges. Snow covered vegetation force the bison to dig into the snow to forage for food. They use their massive heads like a snowplow to clear away snow to reach the grasses below. In heavy snow years, bison may become trapped in a foraging area and not be able to reach new food sources, contributing to starvation.
The snow plowed roads and snowmobile trails in Yellowstone have contributed to an improved survival rate of the bison. They are able to move to new foraging grounds by using the roads and trails.
One last point, the proper name is Bison, not Buffalo. Buffalo (water buffalo) are found in Africa, not America.
View this short video of bison foraging in the snow: