Living with urban wildlife
Beaver are a species that have gotten a bad reputation over the years. In spite of being resented by some farmers and homeowners because of the damage beavers may do to trees and because of the flooding sometimes caused by their dams, beaver can be extremely beneficial to the environment by producing wetlands.
To prevent damage to trees, wrap the trunks with hardware cloth or metal flashing to a height of at least four feet, or in areas where flooding is common, at least two feet above the high-water mark. Securely fasten the wire to the bottom of the tree and check it every year or so to make sure it does not inhibit tree growth.
Some people have successfully protected areas from beaver by using field fencing or a single strand of electric fence placed one-foot high around the area.
Removing beaver dams is a waste of time, for beaver will quickly rebuild. Trapping and killing these animals is only a short-term solution, as other beavers will move into an area.
Beaver only need for the water to be deep enough to allow underwater access to their den entrance. You can modify a beaver dam to avoid flooding and still allow the beaver access to its home. A 12-inch diameter culvert pipe can be placed through the dam at the level you want the water to remain. Extending beyond the dam and protected by a wire barrier covering its end, the culvert allows water to flow through the dam but provides enough depth so that the beaver still has access to its den.
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