Bison seem to be very bony in the spring; how many die during the winter?
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.
