The American Beaver (Castor canadensis) is the largest living rodent in North America. Once among the most widely distributed mammals in North America, beavers were trapped virtually to extinction in the 1800s to meet demand for beaver pelts. A subsequent decline in demand, coupled with proper wildlife management, allowed beavers to become reestablished in much of their former range, and they are now common in many areas, including urban settings.

Beavers are semi-aquatic and prefer to remain in the safety of the water as much as possible. They are fairly common in Colorado, including in urban areas. In Castle Rock, beavers are active along East Plum Creek and Sellars Gulch. However, you might not catch a glimpse of these animals as you walk along the creeks during the day, since beavers are active mostly at night.
Beaver in the Water

Cutting down trees and the benefits

Beavers use the trees they cut down for food, and they use the left-over branches for building materials for their dams and lodges.

Beavers are well-known for their tree felling and dam building, which creates deep water ponds for protection from predators, for access to their food supply and to provide underwater entrances to their lodges or bank dens.

Although the felling of these trees may appear destructive, such culling can result in more, bushier growth next spring. For example, each willow stump may re-sprout three to four new stems, while poplars tend to regrow from their roots. The wetlands and large ponds created by beaver dams can have great benefits such as water cleansing, erosion abatement, flood control and more biodiversity for other wildlife.

Painting trees

When concerned about the loss of native trees such as cottonwoods and willows along creeks, certain individual trees can be protected from beavers' chewing and girdling activity. An easy and more effective alternative to caging and wrapping trees is to coat tree trunks with a sand and paint mixture that may prevent gnawing, as beavers may dislike the gritty feel of the sand in their mouths.

This is a great work project for scouts or other volunteer groups that requires little oversight after target trees have been identified for protection. In the last few years, the Town has painted almost 200 native trees. If your group or troop is interested in helping paint trees in Castle Rock, please call the POST Partners Volunteer Coordinator Marcy Jones at 303-814-7456.