Beavers are well-known critters across Canada. They are one of our national symbols and they played an important role in the expansion of this country. They are industrious, hearty, and can be found in all of Alberta’s natural regions with the exception of the alpine. They do, however, have a contentious relationship with humans as many people view them as a nuisance.
Beavers can live almost anywhere there is a permanent water supply and plenty of trees, particularly Aspens. Trees are a necessity in the life of a beaver and their use of them is twofold. First, trees make up a large part of a beaver’s diet. They will also eat willows, other shrubs, various grasses, and some aquatic plants. Secondly, trees are required in the construction of their dams and lodges. In addition to trees, other woody plants such as willows, and mud, are also used throughout the construction process. In this way, beavers are the engineers of the animal world. They modify the environment to make it more habitable for themselves and, as a result, many species of fish and other wildlife also find it especially suitable.
Beaver dams act as speed bumps, slowing the flow of water which eventually creates a pond upstream of the dam. The beavers will then use the newly ponded area as their home. They will build a lodge and maintain/expand the dam as needed to keep water levels at an acceptable depth. Sometimes they will even create a series of smaller dams up-or-downstream of the main dam to allow access to food, construction materials, and/or safety. There are many positive impacts to the environment that occur as a result of this process. The slowed water reduces erosion and allows for sediment deposition, resulting in improved water quality and stream habitat complexity. Their dams create wetland habitats that are utilized by birds and other wildlife. Fish species are able to navigate their way through streams with beaver dams while the deep ponds provide effective overwintering fish habitat. Beaver ponds are also effective at mitigating the effects of floods and storing water during periods of drought.
As beavers go about the development and maintenance of their habitat the number of trees in the area will be reduced, and the potential for excessive flooding is heightened. In wilderness areas this isn’t necessarily an issue, however when that flooding threatens infrastructure, roads, or trails peoples’ tolerance wears thin. Thankfully, us humans are also adept at engineering and have designed a device to reduce the risk of flooding. Enter the pond leveler.
Pond levelers are one beaver coexistence tool that can help mitigate flooding risks. Essentially, the pond leveler is a water regulation tool that allows for management of the depth of the pond upstream from a beaver dam with a strategically placed pipe at the dam. Pond levelers will allow beavers to remain at the site but will reduce the risk of flooding human-built infrastructure. If the leveler is placed in the home pond where the lodge is located, the pond will stay deep enough that it won’t freeze to the bottom during winter and the entrance to the lodge would remain submerged at all times. The West Bragg Creek pond leveler was installed at the dam downstream from the main pond where their lodge is located. This pond leveler was needed to help prevent Mountain Road from being flooded.
Pond levelers aren’t the only coexistence tool at our disposal either. Tree wrapping, the practice of placing wire mesh around the base of a tree, is another effective coexistence method that can protect specific trees from being felled by beavers. Another productive strategy employed in the West Bragg Creek area was to raise the low spot along Mountain Road that was of most concern for flooding. All of these strategies were used to mitigate flooding risks while allowing the beavers to, well, be beavers. As of this writing the methods that have been deployed are working as planned, making this project a success story in human-beaver coexistence. The project team continues to monitor the pond leveler on an ongoing basis to ensure its effectiveness.
Once prized for their pelts, the beaver was hunted to near extinction in North America. Conservation efforts have brought the species back from the brink. Now they are cherished for their abilities to store water and improve its quality. Due to recent research and modern engineering techniques we now know that coexistence with beavers is not only possible but beneficial to all of us.
This stewardship project was made possible through a grant from the Alberta Environment Watershed Resiliency and Restoration Program and the dedicated work of staff and volunteers from Bragg Creek Trails, Elbow River Watershed Partnership, Alberta Parks, and the Working With Beavers Collaborative (Cows and Fish and Miistakis Institute).
Photo Credit: Cows and Fish
