Living with Beavers in Manitoba

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1 Living with Beavers in Manitoba A Bit About Beavers (Castor canadensis) lodges and dams, and they all share food with each other. Juvenile beavers leave their family units when they are about two years old to form new colonies - usually downstream. Beavers are herbivores (plant eaters) and their diet varies with the seasons. During the spring and summer, beavers prefer aquatic plants and other tender green plant shoots. As winter approaches, they become increasingly dependent on woody vegetation and will collect and stockpile green woody vegetation extensively. They store this vegetation in an underwater feed pile near their lodges, from which they will feed over the winter. Beavers prefer hardwood tree species such as poplar, birch, alder, maple, willows and their particular favourite, trembling aspen. Beavers are found throughout Manitoba, wherever suitable aquatic habitats exist. They are typically found in larger bodies of water, such as lakes, rivers, streams, ponds and wetlands. Often, they also live in roadside ditches, drainage ditches and sewage ponds. However, as semi-aquatic animals, beavers need a combination of wetland and upland habitats to survive. Water gives them a location for shelter (their lodges), protection from predators and a place to store food, while land gives them food and materials for building dams and lodges. Beavers are social animals. They usually live in family units, consisting of two to 12 animals, including the parents, kits and yearlings born the previous spring. All family members help to build and maintain Beavers are well-known for the structures they build. They create their own shelters, typically by constructing a lodge formed from a pile of branches, sticks and mud. Alternatively, they may create a bank den by digging holes in the banks of a lake, pond, river, creek or even ditch in which they live. The ability to build beaver dams is an instinctive survival skill for the species, which is stimulated by the sound of running water. The dam forms a pond and stabilizes the level of a flowing body of water to the beaver family s preference. This pond provides protection from predators, and because it usually doesn t freeze to the bottom during winter, provides access to the food supply they ve stored underwater.

2 Beaver Benefits Beavers provide many ecological, economic and aesthetic benefits. Beavers create significant riparian and wetland habitats that support a variety of wildlife. For example, resident wildlife use beaver ponds as a water source. Many migratory birds rely on these critical wetlands for nesting and foraging areas. Increased wildlife in the area means hunting and wildlife viewing opportunities increase. The deeper pools of water formed behind beaver dams can often support year-round fish populations, leading to food sources for many mammal and bird species and increased fishing opportunities for people. Beaver-created wetlands retain water for the area in which they re located. The storage area and resulting vegetation act as a filtration system that traps sediments and improves water quality. These wetlands can maintain more surface water over a longer period of time, which improves access to water for livestock and helps with drought resilience for farm production. The sediment left behind when the beavers abandon the area can increase the soil fertility in the resulting meadow. Human-Beaver Conflicts Conflicts with beavers can happen if their eating habits or dam/den building cause damage or flooding on people s property (ex: trees, fences, roads and crops) or when they transmit disease to people. How can I protect my trees? Several methods are available to protect your trees from beaver damage. These methods include tree wrapping, fencing and abrasive tree painting. Tree wrapping involves using wire mesh fencing to form a cylinder around the base of the tree. You can use an abrasive paint mixture (mason sand mixed with exterior latex paint) to keep beavers from gnawing on mature trees, not saplings. However, abrasive painting may not be as effective as the tree wrapping technique. If a number of trees need protection in a reasonably small area, it may be more cost-effective to fence around the stand of trees. Because beavers are good diggers, the entire fence must be installed in contact with the ground, so there are no gaps for the beavers to exploit. For uneven terrain, or a more pleasing look, you can build electrified fencing at a height of 10 centimetres above the ground. Abrasive Tree Paint Abrasive Tree Paint Close-up Tree Wrap Tree Wrap Close-up 2

3 What can I do about beaver dams causing unwanted flooding damage to my property? You can consider two options for beaver dam management when beaver activities are flooding your property: installing a pond leveler or removing the dam. In both cases, you need authorization from Manitoba Sustainable Development before undertaking these activities. Contact your local Manitoba Sustainable Development district office to request authorization. You need to provide a legal land description of where the dam management activity is to occur. A pond leveler reduces and maintains pond water to a desired level. It can be inserted through a beaver dam or a culvert. The multiple holes on the pond lever intake end allow for the slow, quiet movement of water, and discourage damming behaviour by a beaver. Because beaver damming behaviour is stimulated by the sound of running water, studies have shown that by removing that sound, the beaver is not motivated to build or repair a dam. The screened intake area of the leveler keeps debris out and discourages plugging. However, the device may need some maintenance to ensure the screened intake area stays sufficiently clear of debris to allow adequate water-flow. Removing a beaver dam is generally a temporary solution and should only be considered after other techniques have been tried, or if they are unsuitable for the area. In most cases, removing a dam will also mean the beavers associated with the dam will need to be removed. If dam removal is necessary, it is important to exercise extreme caution to prevent downstream flooding, damage to natural habitats and property damage. If you remove a dam, you may be held liable for any property damage that occurs downstream because of your actions. You will need a permit to remove a dam. Further, if activities are to be conducted on Crown land, a Crown Land Work Permit may also be required. Consult your local Manitoba Sustainable Development district office to find out what permits and conditions apply. Federal laws require that projects do not cause serious harm to fish. If you are considering beaver dam management activities on fish-bearing waters, consult with the federal Department of Fisheries, Oceans and Canadian Coast Guard to ensure you are complying with all federal regulations: Installed Leveler 3

4 What can I do to prevent or clear beaver blockage in a culvert? In Manitoba, clearing beaver debris from a culvert does not require prior authorization. Once cleared, or for culverts with a high potential for beaver blockage, installation of a beaver deceiver or pond leveler is recommended. Numerous design options for both devices are available. Where site conditions allow, the most effective beaver deceiver is the trapezoidal (four-sided) fencing system, with a minimum total length of 14 metres, plus a top and bottom side. You should also think about the substrate on which the deceiver will be installed. If it s on uneven ground, leveling the ground will allow for easier installation. This type of beaver deceiver is generally built on-site and adjusted as needed to meet the site s requirements. WATER FLOW CULVERT Diagram of a trapezoidal (four-sided) Beaver Deceiver showing the fencing above the water line. 4

5 Why not live trap and relocate beavers? Relocating trapped beavers can create a new set of problems for the beavers, other wildlife and people: Beavers may be released in an area where other beavers already live.the resident beavers may attack and seriously injure or kill the relocated beavers. Relocated beavers may carry diseases to wildlife in the release area. Trapping and relocating animals late in the season may not leave them enough time to build their lodges and store enough food to survive the winter, leaving them vulnerable to death by starvation or exposure. The relocated beavers may cause conflicts with new, surrounding landowners. For more information about managing human-beaver conflicts, please visit and click on Beaver. What is the Growing Assurance Farmland Beaver Damage Control Program? This program provides funds to rural municipalities, Northern Affairs Community Councils and First Nation Community Band Councils for assistance in preventing beaver flooding damage to agricultural land. Eligible program activities include beaver removal, beaver dam removal and the construction and installation of pond levelers and beaver deceivers. The Farmland Beaver Damage Control program is funded through Growing Forward 2, a federal-provincial-territorial initiative. For access to the program application, and for more information about the Growing Assurance Farmland Beaver Damage Control Program, please visit and click on Growing Forward 2. What can I do to prevent transmission of disease from beavers to people? Beavers may carry parasites and diseases such as tularemia and giardia (commonly known as beaver fever) that can be transmitted to humans. It is recommended that you take proper precautions when you re in contact with beavers or the waters in which they may be found. Use good quality rubber gloves when you re handling beavers and thoroughly wash your hands with soap and water after handling beavers or coming into contact with water where they may be present. Do not consume water in which beavers may be found, without having first boiled it for a minimum of one minute or ensuring it has been adequately filtered or chemically treated. If you suspect you may have become infected, see your doctor or health care provider. For more information on communicable disease control, please visit: 5