Celebrating a Wildlife Success Story – Learning to Live with Beavers (again)

April 9, 2025

By: Erin Parker, Interpretive Services Supervisor

Can you think of an animal that creates wildlife habitat for itself and other species, helps with flood control, and even develops new wetlands? If you immediately thought of the beaver, sometimes called nature’s engineer, you’re right! April 7 was World Beaver Day and their return to our parks and landscapes is something that should be celebrated…even though re-learning to live with beavers can provide some challenges, too.

North American beavers (scientific name Castor canadensis) are considered a keystone species, one that alters its ecosystem so much that other animals depend upon its presence and that its removal causes dramatic change. They spend their lives in, near, and even under water with thick, glossy fur that was once prized for clothing and hats. Hunting for this beautiful, warm, waterproof fur drove them to near-extinction in many parts of North America in the 1800 and 1900s. Their impacts on our landscapes were lost as development increased in places that beavers had once actively managed.

American beavers are large rodents that live in family groups. Young beavers, called kits, live with their parents and siblings for up to two years before dispersing and finding their own watery homes.

Diet and Disruption

Beavers are herbivores well known for their habit of cutting down trees with their strong, ever-growing teeth. But have you ever considered what they’re actually after? Beavers are big, sturdy animals with large, webbed back feet and a large, flat tail. They can’t climb, so when they want to reach the tender leaves, buds, inner bark, and young twigs that grow at the top of trees like willow, aspen, dogwood, and others, they must cut the tree down. They will also eat aquatic vegetation such as water lilies and even plants like ferns and sedges that grow along the water’s edge. But it is their habit of taking down people’s favorite trees and their seeming inability to ignore running water that get beavers in the most trouble with their human neighbors!

Beaver Dams

Beavers build lodges either on the banks of rivers or streams or in the middle of ponds and other larger bodies of water. This protects them from predators like coyotes (and wolves and large cats where they coexist). Beaver dams, built by the beavers of cut logs and mud, are designed to slow moving water into a spreading pond or pool, creating safe surroundings from their possible predators. Running water, including water moving through a culvert designed to keep water off of roads or property, must seem like a leak that needs to be repaired in the minds of the beaver builders.

While beaver ponds can increase the diversity of wildlife in an area as it provides new habitat as well as a water source, these can be less appealing to humans when they occur on roads, trails, or other private property. While the engineering feats of beavers may seem deeply frustrating to people, there are many ways to help humans and beavers to get along.

Beavers, like all rodents, have teeth that are constantly growing and have an iron-rich enamel that keeps them strong. These animals are always chewing, gnawing, biting, and even grinding their teeth to keep them short and strong- in fact “rodent” comes from the Latin words for “to gnaw”.

Beaver Deceivers and Protecting Beloved Trees

Beavers play such an important role in the landscape: from creating new habitats to helping with stormwater filtration through slowing water movement and even reducing wildfire risks by adding natural impoundments to contain and store rainwater. But their near eradication from our natural and built ecosystems for the last 150+ years means that they can aggravate us with their persistence and their creative engineering!

Luckily, many people are willing to live with beavers while simultaneously preventing the beavers from flooding out roads, trails, and structures. There are a variety of ways to create and install a “beaver deceiver” which is essentially a pipe under the water in a dam or culvert that allows the water to move through without the beavers noticing. Research suggests that beavers may try to plug perceived leaks when they hear water trickling at the surface, and the deceivers work by being entirely submerged. Beaver deceivers come in many shapes, sizes, and designs that are created for each site’s unique needs. Once a deceiver is installed, beavers may patch their dam or culvert, but the water in the deceiver can continue to flow unimpeded by the busy rodents’ hard work.

Another problem that beavers can cause is the destruction (and consumption) of beloved trees. Beavers prefer willow, aspen, cottonwood, and other leafy trees over conifers and they are capable of easily taking down fully grown trees. To protect trees from beavers, the use of fencing, paint mixed with sand, and wire cages can be used. Beavers are much larger than most people realize, and trees must be protected at least four feet up the trunk. A full-grown adult beaver can weigh up to 70 pounds and stand 1.5 feet tall.

Beavers patrol their ponds and waterways at dawn and desk, swimming loops around their dams and homes. If they feel threatened by predators or people, they’ll slap their broad, flat tails on the water and dive below to safety.

Viewing Beavers

Beavers are nocturnal so even as they’ve made a comeback into Michigan’s freshwater ecosystems, they can be difficult to find. If you see signs of beaver, including the tell-tale cut stumps along a lake or stream edge, look for beavers patrolling their watery homes at dawn and dusk where they’ll swim with their big, blocky heads out of the water. Many of our local parks, including Lake St Clair and Oakwoods Metroparks, have beaver dams and activity visible from shore.

Resources and more information

https://www.beaverinstitute.org/

https://www.illinoisbeaveralliance.org/2025-midwest-beaver-summit

https://www.illinoisbeaveralliance.org/

Share This