Beaver
Castor canadensis
Body Weight:5-40 kg
Body Size:70-90 cm
Species Status:Common / Least Concern
Legal Status:Furbearer
Natural History & Behaviour
Herbivore, Ecosystem engineer
Beavers are ubiquitous across Alberta and Canada, and can be found anywhere there is sufficient flowing water and food vegetation to support a colony. They live in colonies that may exceed 20 individuals, and breed in February with litter sizes averaging 4-5 kits.

An average beaver colony consumes roughly 100-150 trees/year, primarily deciduous trees with a preference for aspen and poplar. They build lodges and dig dens in banks along water courses, and cut down trees to construct their lodges as well as dams and other earthenworks aimed at cutting off drainage in an area. By winter, the beaver colony would have created a standing pond in which they stash green stems and branches under-ice as a food source protected form freezing and predators.
Beaver-caused Damage
High risk to property & infrastructure, low risk to public safety
The greatest threat beavers pose to human property and infrastructure is through flooding and water damage. Beavers are highly efficient and obligate dam builders compelled by instant to plug any flowing water features. They do not limit dam construction to streams and creeks; culverts, storm drains, pond inlets and outlets, and sometimes even sizable rivers can be partially obstructed if not fully dammed. Dams and blockages once in place can flood large areas in relatively short periods of time, especially following rainfall.

The flow-obstruction instinct of beavers also wreaks havoc with industrial water intakes and drains, sometimes in hard-to-reach areas, causing silt accumulation, machinery damage, and work stoppages until they can be removed and flow restored.

As tree herbivores, beavers can also damage and destroy significant trees in parks and subdevelopments with wetland and pond features, damage which can accumulate to tens of thousands of dollars for the costs and values provided by planted trees. A tree in the process of being cut down by a beaver is also a significant public safety hazard on windy days.

Beavers in general do not attack humans and avoid contact unless habituated. They are capable of carrying rabies, but actual rates of occurrence are very rare.
Damage Mitigation
Dam Breaching, Beaver Removal, Follow-up monitoring
Where there is an existing flood or blockage, ADC can breach the dam and open the channel regardless of its size and location. To keep costs and risks down, we typically break small dams by hand and larger dams with power machinery. In extraneous circumstances or with the largest, difficult-to-access dams, we can breach the dam using explosives. We are the only company with explosives safety certification and clearance for beaver dam blasting in Alberta.

When a dam has been breached, beavers will immediately begin to repair the damage and restore the obstruction. The resident beavers must thus be removed to remove the root of the flooding problem. ADC is the most highly respected and reputed firm in Alberta conducting beaver removal using effective, humane methods with a commitment to international ethical standards.

Even in an area without beavers, dispersing beavers can establish new colonies a long distance away from their original habitats, including in wetlands and ponds in the middle of suburban and urban developments. With the exception of removing their primary food sources (deciduous trees), there is no other way to deter them from settling in a new area. It is thus necessary to monitor water bodies and riparian areas where their establishment would pose a threat to human property and infrastructure, and remove them proactively at first sign in the summer before they establish and construct dams. Capture and release methods are considered less humane in the winter as beavers would suffer from exposure and predation in an unfamiliar area away from their constructed shelters.
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