Adult beavers can weigh between 35 and 60 pounds, making them the largest rodents in North America. When beavers are alarmed they slap their tails against the water to alert other beavers in the area, then dive into deep water for protection. Though excellent swimmers, they are slow and awkward on land, which makes them vulnerable to predators. Beavers will always head for water when they feel threatened. They can reach speeds of up to 6 mph.

Beaver are specially adapted to spending much of their time in the water. Their nostrils and ears are closable, the hind feet are webbed, their fur is kept waterproof from an oil gland, and their eyes have a transparent membrane so they are able to see under the water. Their large round tail is used as a rudder while swimming.

Males and females reach sexual maturity at about 21 months. Once mature, they will breed every year around February and they tend to mate for life. Gestation lasts from 105 to 107 days. In May they will have a litter of three to five kits. The kits are born fully furred with open eyes. Two weeks after birth they are ready to make their first venture outside the lodge. They are weaned within two months, but will not leave to seek out their own territory until they are two years old.

Beaver tracks are rarely seen in winter. They cut and anchor wood on the pond floor for winter food. A lodge in winter may contain a number of beavers. In winter, a family would contain two adults, two or more yearlings, and two or more kits born in the last spring. In the coming spring, the yearlings are driven from the area and must start a life on their own.

Indians used to harvest beavers in winter. After the lodge froze, the hunter would chop a hole in the top with an axe. The beaver family would be hiding inside. Another person would climb into the hole and remove the beavers one at a time, passing them out to the hunter. The biggest beaver was removed first, followed by the smaller ones, so that the big ones did not fear for the little ones. The hunters showed respect and no fear so that the beavers would allow themselves to be taken without biting the person removing them from the lodge. Also, the person who first went in the house would finish lifting all the beaver out; to change places would make the beavers scared of the hunters, and they could bite, scratch, or dive away to die a slow death under the ice without their lodge. After the beavers were caught, they were killed with a club, skinned, and cleaned.

Wild beavers live about 11 years, unless they are trapped or killed by predators. They are not so graceful or speedy on land, however, and there they are most vulnerable to predators. Beaver predators include bears, lynx, wolves, and wolverines.

The ponds, wetlands, and meadows formed by beaver dams increases bio-diversity and improves overall environmental quality. Beaver dams are the primary natural method of establishing wetlands. The increased “typical reserve” behind a beaver dam is of significant benefit to wildlife and fish during periods of drought. They reduce the amount of sediment loading in rivers and streams and provide a stable water supply for wildlife and vegetation.

Despite the many positive effects of beaver on water quality and the creation of wetland habitat, beavers can become a nuisance. When beavers begin constructing dams near homes, they can flood low lying areas and damage backyard trees. Other problems include flooded roads, redirected stream flows, loss of large specimen trees, and higher water temperatures.

Preventing Flooding: A trickle leveler is a perforated pipe placed through a dam which allows water levels to be stabilized. The beavers continue to maintain their dam while the leveler prevents flooding of adjacent roads or yards.

Preventing Damage to Trees: If beavers in the area are damaging trees on your property, a simple fence 3 to 4 feet high made of heavy wire mesh can prevent damage. The fence should be approximately 8 to10 inches from the plant, and can be supported by driving metal rods into the ground to which the fence can be tied. A low sturdy fence, three feet high, can keep beaver out of an area entirely.