The Great Outdoors: Seeing Beavers in Action a Rare Treat

dreamstime_xs_46337435I find all types of wildlife interesting in their own individual ways, but the beaver is perhaps the most remarkable critter in nature.

They are exceptional engineers, using their upper and lower incisors to cut down hundreds of trees, which they use to build dams and lodges. Actually, beavers have to cut continually because their teeth never stop growing. Constantly gnawing on wood offsets the growth.

Typically, beavers cut trees that are less than 100 yards off a waterway’s edge, so they can drag them without being exposed for a long time to predators such as bobcats, coyotes, or bears. In some instances, beavers will dig a canal from the pond inland to aid in floating the logs back to the dam. Beavers typically build their dams on streams and creeks rather than rivers because of the volume of water.

Wildlife experts believe dam building is instinctive rather than learned.

Wood cuttings packed with mud and rocks form the dam. Most of the stream flow seeps through, but the dam backs up a barrier of water around the home lodge where the beavers spend their time when not at work and raising their young.

According to the Pa. Game Commission’s Field Note by Chuck Fergus about beavers, the lodges are dome-shaped islands of sticks and logs plastered with mud. A lodge’s interior compartment (the den) may be up to five feet high, with a small air hole at the top. The mud freezes in winter, making the lodge impregnable to predators that might visit.

Along fast, turbulent streams — or creeks and rivers too wide to dam — beavers either burrow deep into the bank or build lodges at the water’s edge. The entrance to a lodge (whether it’s on the bank or in the middle of a pond) is always below water level, while the den is dry and above water.

According to the PGC’s Field Note, the thick pelt and deposits of body fat insulate the animal and allow it to remain in the water many hours at a time.

A beaver’s tail is trowel-shaped, eight to 12 inches long and five or six inches wide. It has a scaly, leathery covering. When the animal swims, it uses its tail as a propeller and a rudder; the tail also supports a beaver when it sits erect or gnaws a tree on dry land. A sharp slap of the tail on water is a signal warning other beavers of danger.

A beaver’s front feet are remarkably dexterous. They have long claws and are used for digging, handling food, and working on dams. The thumb is small and weak, but the little finger is strong and has taken over the thumb’s role.

The hind feet, broad and webbed between the toes, propel the animal through the water. The second claw from the outside on each hind foot is double (or split) and is used for grooming.

A beaver’s vision is weak, but its hearing and sense of smell are acute. Most food is located by smell.

Beavers are slow on dry land but quite mobile in the water. A beaver can stay submerged up to 15 minutes; membrane valves seal the ears and nostrils while it’s submerged.

Beavers do well in environments that have maple, aspen, and willow trees. They may cut up to 300 trees a year. Most trees are less than three inches in diameter.

Experts say in average conditions, an acre of aspen can support a five- or six-member colony for 1 to 2 1/2 years.

Dam building has positive and negative effects.

Water that covers the base of a tree will eventually kill it because the tree’s roots cannot get oxygen. The dead trees become homes for various cavity-nesting birds.

The ponds are a good habitat for ducks, geese, shorebirds, fish, reptiles. and amphibians. Otters, raccoons, mink, herons, ospreys, hawks, owls, and other predators are attracted by the rich variety of life and food. After the beavers exhaust the supply of winter food in the area — this may take 10 or more years — they move on. But, that doesn’t mean life withers in the area.

When a dam does give way, the water drains off, leaving an open area where grass grows in the rich soil. Later, berry bushes and shrubs spring up. Insects and small rodents thrive in the new habitat. Deer, bear, grouse, turkeys, songbirds, and insectivorous birds come to these beaver meadows, which provide edge and openings in the forest. The stream continues to flow through the meadow among standing dead trees.

Seeing beavers in action is a rare treat. They are active after dark, but a good bet to see one would be to stake out a pond at first light or near sundown.

In our region, we are fortunate to have a good beaver population, so seeing one or more is possible.


“The Great Outdoors,” sponsored by the Pennsylvania Great Outdoors, is a weekly blog by’s Scott Shindledecker. Plan your next outdoor adventure at or call (814) 849-5197 for more information.

Copyright © 2021 EYT Media Group, Inc. All rights reserved. Any copying, redistribution or retransmission of the contents of this service without the express written consent of EYT Media Group, Inc. is expressly prohibited.

Comments are temporarily closed. A new and improved comments section will be added soon.