American Beaver: Reflecting on the groundhog’s keystone cousin

Beaver in water with stick

There’s a lot of excitement this time of year about groundhogs and seeing shadows, but among the things water enthusiasts are excited to see any day of the year are signs of the largest living rodent in North America: the groundhog’s Rodentia cousin, the American Beaver (Castor canadensis).

Beavers may be far more likely to see their reflection than their shadow, but a shared trait of these two related species is their continuously growing incisors, which are worn down by use.

According to the Oregon Department of Fish and Wildlife: “Although beavers are nocturnal, they are occasionally active during the day. They do not hibernate but are less active during winter, spending most of their time in the lodge or den. Freshly cut trees and shrubs and prominent dams and lodges are sure indicators of beaver presence. Look for signs of beavers during the day; look for the animals themselves before sunset or after sunrise. Look for a V-shaped series of ripples on the surface of calm water. A closer view with binoculars may reveal the nostrils, eyes and ears of a beaver swimming.”

Beavers were trapped nearly to extinction in the 1800s, but thankfully they are making a comeback; as a keystone species, their activity indicates successful natural enhancement efforts. Because beavers are a native and beneficial species, we do not disturb them unless their activity is flooding a structure or damaging the public drainage system. If you observe beavers causing this type of activity, call our Field Operations staff at 503.547.8100.

Check out this short video to learn about how beavers positively impact their natural habitats:


Learn more about both the beneficial and the problem species living in our watershed:

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