American Beaver (Castor canadensis)

Description

A very large, bulky rodent, with rounded head and small, rounded ears. Dark brown fur is fine and soft. Scaly tail large, black, horizontally flattened, and paddle-shapped. Large, black, webbed hindfoot has 5 toes, with inner 2 nails cleft. Eyes and ears are small. Large, dark orange incisors. They can weight anywhere from 44 to 60 lbs, and as much as 86 lbs.

Food Habits

Beavers feed on the bark of poplar, aspen, willow, birch, and maple as well as succulent plants. In late summer and fall they store tree cuttings in an underwater food pile, to be eaten in winter.

Reproduction

Beavers mate in late January to late February and are believed to mate for life. After 4 months, kits are born. The litter usually contains 4 to 5 offspring, but may contain anywhere from 1 to 8 offspring. Kits are born well furred, with eyes open, and weighing about 1 pound. They may take to the water inside their lodge within a half hour and are skillful swimmers withing 1 week. The young remain with their parents for two years and are driven away just before the birth of a new litter.

Habitat

Beavers live in and along streams, rivers, marshes, and small lakes surrounded by the trees they typically feed on. Famed for their dam-building ability, they begin by making an underwater foundation of mud and stone. Then they gnaw down trees, leaving characteristic cone-shapped stumps, and drag or float cuttings to the dam site, where they are incorporated into the foundation with more mud. As a pond forms behind the dam, the pair of Beavers build a stick-and-mud lodge with underwater entrances and an inside platform raised above the water. Here they remain much of the day, emerging at dusk to forage.

Beavers had been hunted extensively in the 19th century for their pelts. The fur was in constant demand for robes and coats, clothing trim, and top hats that were fashionable in European capitals and in urban areas of the eastern U.S. Some of America's great financial empires and real estate holdings were founded on profits from the trade in beaver fur. Unregulated trapping continued for so long--well into the 20th century in some areas-- that the American Beaver disappeared from much of its original range. Now restored as a population, the American Beaver has become an agricultural pest in some regions, and it kills many trees, most of little timber value. Its dams may block the upstream run of spawing salmon and flood stands of commercial timber, highways, and croplands, or change a farmer's pond or stream into a slough that will eventually become a medow. However, the dams also help reduce erosion, and the ponds formed by the dams may create favorable habitat for many forms of life.

Best viewing on campus

Beavers may be found in many of the bodies of water on campus and have been seen in Piles Fork creek bordering the east side of campus.