European bison

The European bison is the largest mammal on the continent. Large bulls can stand over 6 feet tall, be longer than 9 feet, and weigh over 2,000 lbs. Males are larger than the females, but both sexes have short horns (TUUP, 1999.). A thick shaggy mane covers the head and neck, and in the autumn the bison put on an extra thick coat of hair to ready themselves for the winter, where temperatures in January average 25 F, and snow cover persists, on average, 92 days a year (Falinski, 1999).
The female bison usually live in herds of around twenty to thirty animals (Burton & Pearson, 1987). Herd sizes vary due to their seasonal cycles – breeding, calving, and chance encounters with other groups determine the number in a group (Krasinski,1990). During the calving season, which usually lasts from May to July, cows leave the herds and give birth to one calf, sometimes two (Riccuiti, 1973). Gestation period for the cows last between 254-272 days (TUUP, 1999). Within days of the birth, calves are on their feet. Weaning lasts from four to six months. The female calves will reach sexual maturity in about two years, while the males at about eight years. Bison can live to be over twenty-five years old (TUUP, 1999).
During the winter months the cows and their calves congregate into larger herds, where they gather at two remote feeding stations. Although the bison gather in larger herds in the winter, each animal acts on its own, with little coordination in their activities. (Krasinski,1990). Some of the older bulls form small herds, but most bulls keep to themselves. In historical times, winter served as an aid in the natural selection process, as the scarcity of food and colder weather weeded out weaker animals. Some scientists also believe the bison...

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