Q: Beavers are causing flooding on my property. Will trapping or other lethal means solve my problem?

A: Killing beavers and busting up the dam will, in the very short-term, solve problems with flooding and tree loss. But, since there is suitable habitat, more beavers will just move in and the problem will reoccur. It is well accepted that lethal control is a short-term solution. It simply creates an opening that a new colony will soon utilize. In addition, many people are looking for more progressive solutions to wildlife problems than the “just kill it approach”. The good news is that there are effective ways to coexist with beavers.

Q: If lethal controls do not work how can I solve beaver problems on my property?

A: There are many problems with the established approach of killing beavers. In addition to being short-term, it is costly, leads to the loss of vital wetlands and biodiversity and, therefore, the public is becoming increasingly opposed. For these reasons there have been on-going efforts by wildlife agencies and others to find alternative solutions to problems such as tree loss and flooding. Initially, flow devices proved inconsistent and often ineffective. However, recent design improvements have led to high success rates. Here are the major ways beavers can cause problems as well as ways to solve these problems:

1) Blocked culvert- In situations where beavers are blocking a culvert and preventing water to flow, a culvert protection device is a very effective, long-tern solution. By protecting the upstream culvert the beaver cannot dam it effectively, meaning water will continue to flow. The device involves securing posts in a trapezoidal shape around the culvert and then attaching 4 gauge, 6” steel mesh fencing (also called concrete reinforcing wire mesh). The 6” mesh size allows wildlife including fish to pass through the device. The fencing should be cleaned of debris. In some cases the round fence pond leveler is also attached upstream to further prevent damming of the culvert fencing.

Photo courtesy of the Humane Society of the United States

2) Flooding from beaver dam- In situations where flooding is caused by a beaver dam that is not attached to a man-made structure, a pond leveler device works best. The concept is that a long pipe is run through the dam to allow water to keep flowing and not flood the adjacent areas. It is important that the pipe be long enough to prevent the beaver from hearing the water running, as this is what stimulates the beaver to want to block the flow.

For detailed information about flow devices visit www.beaversolutions.com

3) Beavers chewing trees- If you have beavers on your property, or are near water, protecting your trees is the best way to ensure their survival. There are two ways of doing this:

A) Welded wire or galvanized (to prevent rust) 14 guage fencing wire (2"x4")- This wire is very sturdy and is perfect for making a tree guard that will protect a tree for many years. Since the wire can stand freely you should leave about 4-6" inches around the trunk to give it room to grow. Remember the guard must extend 2 feet higher than the highest snow level, typically a 4 foot high guard works in most winter climates. Cut the bottom of the wire to fit a sloping grade or to protect prominent roots from chewing.

Photo courtesy of the Humane Society of the United States

B) Tree Painting- A mixture of latex exterior paint and fine sand (30 mil or 70 mil) can be applied to tree trunks to discourage beavers from chewing. (Ratio = 5 oz of sand per quart of paint). This is visually discrete as the paint can be selected to match the tree trunk. It is also relatively quick to apply. Mix only the amount you will use as it does not store well and remember to stir the mixture often as the sand will settle. It is also suggested to leave some less desirable trees for food for the beaver. This method is not recommended for saplings less than six feet high, so protect them with wire fencing.