Dirty Face
Bison at Yellowstone National Park. Male (bulls) bison have a height of 6 ft. weighing in at 2,000 lbs. as an adult while females (cows) weigh up to 1,000 lbs. and reach heights of 4-5 ft. Bison calves weigh 30-70 lbs. at birth. Bison have a life expectancy of 20 years.