Beavers have found an inviting home in Calgary, with its two rivers, abundant green space, and lack of predators. In recent years, their population has grown, with lodges in various locations along the Bow and Elbow rivers, in storm water ponds and wetlands.
Beavers are good for our environment
Beavers play an important ecological role in Calgary’s waterways. Their dams can create ponds that provide habitat for other wildlife and help surrounding vegetation to flourish. The ponds and wetlands are very good at storing water, and can help reduce the effects of smaller floods and hold water during droughts.
Water flowing through dammed areas is naturally purified, and after a dam has broken, fertilizer created from the decomposing material in the dam will spread downstream.
Beavers also present some challenges
Because conditions are so good, Calgary’s beaver population has grown in recent years. This can cause problems for our forested areas, infrastructure and property, and the beavers themselves.
A single adult beaver can cut down about 200 trees in a year. With each lodge housing four to six beavers, wooded areas can be devastated in a short period of time. This is harmful to other wildlife that rely on the trees for habitat. Beaver dams can also cause flooding that affects property, and in some cases, can damage storm drains and weirs that can be very expensive to repair.
Without natural predators, beaver populations can grow to be unsustainable.
The City's approach to beaver management
The City’s practice is to try and strike a balance between health of the surrounding areas and the wellbeing of the beavers.
When required, The City uses different measures to protect trees and property to make our river parks unappealing to beavers. Depending on the situation, we may use a combination of the following:
- Placing metal wiring around tree trunks.
- Planting varieties of trees along the shore that are less palatable.
- Placing under-dam drains to control water levels.
We consider all other options before turning to trapping. However, in some cases it is required. When we do remove beavers, we use traps that are designed to kill instantly. The traps are placed under water for the protection of dogs, park users and other wildlife, and are checked daily.
Unfortunately, relocation of beavers to another area is not an option. Alberta Environment and Parks does not support moving beavers. There is a low rate of beaver survival, and an increased risk of the transfer of diseases. Relocation can also upset the balance of ecological functions, and can potentially create future human-beaver conflicts.
How you can get involved
Let us know when you see beaver activity. Though we are conducting our own monitoring, we appreciate updates from park users on what they have observed. If you are concerned about beaver activity, please contact 311 to let us know.
Wire trees on your property
If you own or manage property along a river, you may want to wire your trees to protect them. This how-to video demonstrates what you will need and how to make your trees beaver-proof.