Flow Devices to Control Beaver Damming
Occasionally beavers build dams that can cause significant property, health or safety issues for people.
When conflicts do occur the flooding threat can often be resolved with well-designed water control flow devices. Flow devices are usually the most long-term, cost-effective, humane, and environmentally friendly beaver management tool available.
See the Flow Devices section for many different examples of successful flow devices, including Flexible Pond Levelers for freestanding beaver dams, and flow devices for man-made structures such as road culverts, dam spillways and retention ponds.
BDA Stream and Watershed Restoration
Vibrant ecosystems and healthy watersheds evolved over millennia in response to beaver damming. Following colonial beaver extirpation from the fur trade, many streams in North America eroded and became badly incised. Incision drops the level of the stream bed which also drops the surrounding water table. With severe channel incision the water table drops too low for the roots of nearby plants to reach. Then the native vegetation dies off, and a barren, arid watershed with a loss of biodiversity results. A once vibrant, lush area can become a desolate dust bowl due to stream incision.
Beaver dams reverse and heal incision by slowing water velocity and depositing suspended sediment. However, some streams are so badly incised and the vegetation is so degraded that they are inhospitable to beavers. In these situations man-made Beaver Dam Analogs (BDA) can be installed to slow stream flow and this quickly starts sediment deposition. As the sediment builds up the water table rises, native riparian vegetation returns, channel banks become less steep and eventually beavers can move in to build their own dams to continue the healing process. Scientific studies of BDA’s have proven their effectiveness to reverse stream incision and dramatically accelerate stream restoration, expanding wetlands that attract myriads of species.
Tree Protection from Beaver Chewing
Beavers chop down trees with their teeth for food and building dams and lodges. In addition, like all rodents their teeth never stop growing so chewing wood helps keep them sharp and prevents them from growing too long.
Protecting trees from beaver chewing is a very common concern for homeowners. Fortunately there are ways to protect selected trees without destroying the beaver and its wetland ecosystem.. Most of the following tree protection techniques are inexpensive, reliable, and relatively easy for nearly any person to do in a short period of time.
Commercial fur trapping by European colonists gave rise to the exploration of North America, but it nearly resulted in the extinction of the beavers (Castor Canadensis). In the 20th century as beavers began to return to their historic North American range, beaver-human conflicts sometimes arose and beaver trapping was typically used to resolve these conflicts. However, beaver trapping is usually a short term solution to beaver problems because new beavers will be attracted by the habitat and recolonize the trapped area.