Despite an appreciation for beavers and our best intentions to live with them, beavers can become a problem if their eating habits, and dam or den building activity, flood or damage property.

Jenifer Rees

Before beginning any beaver control action, assess the beaver problem fairly and objectively. Are beaver really causing damage or creating hardship requiring control action? The very presence of beavers is often seen as a problem when, in fact, the beavers are causing no harm. You should also determine the type of damage or problem the animals are causing, and then match the most appropriate and cost-effective controls to the situation.

Once you have decided to control beaver damage, you have three control options: prevention, beaver translocation, or lethal control.

To prevent conflicts or remedy existing problems:

Choose and place plants carefully.

Jenifer Rees

Plant areas with Sitka spruce, elderberry, cascara, osoberry (Indian plum), ninebark, and twinberry, because they are not the beavers’ preferred food plants. Densely plant aspen, cottonwood, willow, spirea (hardhack), and red-twig dogwood because, once their roots are well established the upper parts of the plants often resprout after being eaten. Planting preferred plants away from known beaver trails will limit losses.

Note: Beavers do use plants as construction materials that they might not eat.

Install barriers.

The trunks of individual large trees can be loosely wrapped with 3 foot high, galvanized welded wire fencing, hardware cloth, or multiple layers of chicken wire. Barriers can be painted to make them less noticeable. Welded wire fencing coated with green vinyl that helps the fencing blend in is also available.

Lengths of corrugated plastic drainpipe can be attached around the trunks of narrow-diameter trees.

Figure 6. Various barriers can be used to protect plants from beaver damage. All plants should be protected to at least 3 feet above ground—or the snow line—and inspected regularly. Jenifer Rees

Note: Dark-colored pipe can burn trunks in full sun; wider diameter pipe or pipe with holes in it may prevent overheating problems.

Painting tree trunks with a sand and paint mix (2/3 cup masonry grade sand per quart of latex paint) has proven somewhat effective at protecting trees from beaver damage. The animals presumably don’t like the gritty texture.

Note: Preventing access to food sources may force beavers to eat other nearby plants, including roses and other ornamentals.

Surround groups of trees and shrubs with 3-foot high barriers made of galvanized, welded wire fencing or other sturdy material. (A beaver’s weight will pull down chicken wire and similar lightweight material.) Stake the barriers to prevent beavers from pushing them to the side or entering from underneath. An electric fence with two hot wires suspended 8 and 12 inches off the ground is also effective at protecting groups of plants.

Protect large areas that border beaver habitat by installing 4-foot high field fencing. Keep the bottom of the fence flush to the ground, or include an 18-inch wide skirt on the beaver side of the fence, to prevent beavers from entering underneath.

Groups of plants can be protected from beaver damage by surrounding them with wire fencing.

Apply repellents.

Commercial taste and odor repellents have provided mixed results, perhaps because they need to be reapplied often, particularly in moist weather. Taste and odor repellents are most effective when applied at the first sign of damage, when other food is available, and during the dry season.

Control the height of water behind a beaver dam to prevent flooding.

It may be possible to make a small change in the depth of a beaver pond by notching the beaver dam. Commonly this is completed by removing a one to three foot wide section (notch) out of the beaver dam at the intended depth using hand tools. This keeps the rise in the water level at a minimum by using one or more plastic pipes to continually drain the pond area (see “Flexible Leveler” below. Click to enlarge). For leveling systems to work properly, you will have to have at least 3 feet of water in the pond area for the beaver to stay.

The flow device can be constructed from plastic pipe measuring 4 to 12 inches in diameter, depending on the volume of water in the stream. The end extending upstream from the dam must be baffled to prevent beavers from damming or blocking the pipe.

Prevent beavers from plugging culverts.

To a beaver, a culvert probably looks like a hole in an otherwise fine dam. When they plug the hole, a flooded road can result. However, V-shaped, semicircular, or trapezoidal fences of woven wire mesh can prevent culverts from being plugged. Large flow-control devices that include a solid framework can be covered and used as a deck or wildlife viewing spot.

Note: Installation of flow control devices is complicated and generally requires a permit (see “Legal Status” for information on the Hydraulic Project Approval Permit (HPA) and your local WDFW habitat biologist contact information).

"Beaver deceiver"

Dam removal.

It is pointless to destroy a beaver dam because beavers (frequently many at one time) often begin rebuilding them immediately after they are removed. Furthermore, it may be illegal to remove a beaver dam without a permit.

Live trapping and moving beavers

Live trapping and moving beavers elsewhere (translocating or relocating) is risky. Beavers may not survive relocation and those that do may move large distances from the release site. However, when tolerance or mitigation are not an option, landowners may consider relocation as an alternative to lethal removal. Please note that pursuant to WAC 220-450-030, it is unlawful to take live wildlife, wild birds, or game fish from the wild without a permit issued by the director except as otherwise provided by department rule.

Beaver relocation may be an option pursuant to RCW 77.32.585. With a permit, beavers may be relocated where beaver damage mitigation efforts have failed or are infeasible, where beavers are posing a public health and safety risk, or other irresolvable factors exist. Permitted beaver relocators may move beavers to a site that is unoccupied by other beavers as long as there is cooperation among adjacent landowners and local wildlife officials. A cooperative evaluation of existing habitat quality and potential adverse beaver activity is required. There is no guarantee that beavers will stay where released. They may find attractive habitat and forage on nearby properties. Relocation of entire family units to new habitat is strongly advised over relocation of individuals in order to encourage the beavers to settle near the release site.

To help ensure the survival of beavers, the watercourse at the release site should have a low gradient and the site should have adequate food supply. Beavers should be moved during their principal dam-building period, August to October. This will allow them time to gather a food cache, but limit their time to explore before having to settle in for the coming of winter. It may be helpful to provide beavers with a pickup-truck load of aspen or other trees to use as forage and building material at the release site. This may encourage the beavers to stay nearby.

Click here for more information about beaver relocation or to find a permitted beaver relocator.

Lethal control

Lethal control may become necessary when all efforts to dissuade problem beavers fail. Removing beavers is rarely a lasting solution since survivors have larger litters, and others will resettle good habitats.

Lethal trapping has traditionally been the primary form of controlling beaver damage. If you feel you need to have a beaver trapped, invite a recreational trapper to harvest the beaver from your property. Beaver may be trapped for harvest only during an open furbearer trapping season and with a valid trapping license.

Alternatively, you can hire a private individual who works directly with property owners on a fee basis to resolve problem beaver situations. See "Legal Status" below and Hiring a Wildlife Control Operator for additional information. Note: State wildlife offices do not provide animal removal services.

You may have the option to lethally remove the beaver yourself – see “Legal Status” below. Resources for trapping wildlife that are causing damage are available on the Trapping nuisance wildlife page.

Hancock or Bailey suitcase-type traps are the most commonly used live trap. Due to the weight and dangers associated with suitcase traps, it is recommended that only people experienced with these traps use them. Some success has also come from using a 4 foot long cage trap set right at the water’s edge next to a beaver slide. Bait for live traps include freshly cut tree sprouts or branches of preferred foods, apples, and commercial scents and lures. Shooting beavers that are causing property damage requires skilled marksmanship and is not recommended. For safety considerations, shooting is generally limited to rural situations and is considered too hazardous in more populated areas, even if legal. See “Legal Status” below for more information

Public health concerns

Beavers can be infected with the bacterial disease tularemia. Tularemia is fatal to animals and is transmitted to them by ticks, biting flies, and via contaminated water. Animals with this disease may be sluggish, unable to run when disturbed, or appear tame.

Tularemia may be transmitted to humans if they drink contaminated water, eat undercooked, infected meat, or allow an open cut to contact an infected animal. The most common source of tularemia for humans is to be cut or nicked by a knife when skinning or gutting an infected animal. Humans can also get this disease via a tick bite, a biting fly, ingestion of contaminated water, or by inhaling dust from soil contaminated with the bacteria.

A human who contracts tularemia commonly has a high temperature, headache, body ache, nausea, and sweats. A mild case may be confused with the flu and ignored. Humans can be easily treated with antibiotics.

Beavers are among the few animals that regularly defecate in water, and their droppings (like those of humans and other mammals) may cause a flu-like infection when contaminated water is ingested. The technical name for this environmentally borne illness is “giardiasis.” It is more commonly referred to as “giardia”—derived from giardia, the single-cell protozoan that causes the disease. Another popular term, “beaver fever,” may be a misnomer. It has never been demonstrated that the type of giardia beavers carry causes giardiasis in humans. Giardia cysts persist in the environment to infect a number of mammal hosts through the fecal-oral route. In turn, these animals become infected and pass on more cysts to the environment, thus perpetuating the cycle. Giardia has been found in many animal species, including pets, wildlife, and livestock.

Legal Status

Because beavers’ legal status, trapping restrictions, and other information change, contact your local wildlife office for updates.

The beaver is classified as a furbearer (WAC 220-400-020). A trapping license and open season are required to trap and harvest a beaver. Visit the Furbearer trapping seasons and rules page for more information.

It is unlawful to release a beaver anywhere within the state, other than on the property where it was legally trapped, without a permit to do so (RCW 77.15.250; WAC 220-450-010). Click here for permitted beaver relocator information.

The owner, the owner’s immediate family, an employee, or a tenant of property may trap or kill a beaver on that property if the beaver is threatening human safety or causing property damage (RCW 77.36.030). In such cases, no special trapping permit is necessary for the use of live traps. However, a special trapping permit is required for the use of all traps other than live traps (RCW 77.15.192, 77.15.194; WAC 220-417-040). There are no exceptions for emergencies and no provisions for verbal approval. All special trapping permit applications must be in writing on a form available from WDFW.

To remove or modify a beaver dam or install a water leveling or flow device, you must have a Hydraulic Project Approval (HPA)—a permit issued by WDFW for work that will use, obstruct, change, or divert the bed or flow of state waters (RCW 77.55). A permit application can be obtained from your WDFW Regional Office or from the Hydraulic Project Approval (HPA) web page. For additional information on beaver dam modifications, please contact your local WDFW habitat biologist.

In emergency situations (when an immediate threat to property or life exists), verbal approval from WDFW can be obtained for work necessary to solve the problem. A 24-hour hotline 360-902-2537 is available for emergency calls during nonworking hours. During normal hours, contact your nearest WDFW Regional Office.