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Busy Beaver at Mirror Lake

April 09, 2013 Posted by: BW - Volunteer Interpreter

Observant visitors to Mirror Lake over the past month may have noticed evidence of beaver (Castor canadensis) activity. Several cottonwood trees around the main reflection pool are showing the toothmarks of gnawing by beavers. The beaver is the largest rodent in our area and it lives in and around water. Master civil engineers of the animal world, a beaver will often construct a house, known as a lodge, or a dam out of logs and brush. These persistent fellows can have quite an impact on the immediate area around where they live. Of course, they will only stick around as long as there is food available. That food is mostly the inner bark, or cambium, of cottonwoods, aspens, and willows. In the Sierra, scarce food may force beavers to shift to a new territory every couple of years. The fate of the beaver at Mirror Lake is anything but certain. By most accounts, although beaver was common in the Central Valley, it was not historically present in the higher elevations of the Sierra. Park biologists are aware of the increase in activity in the park and are monitoring the progress. It remains to be decided whether this non-native species can be controlled, or we will have to tolerate its work.

Tree trunk gnawed on by beaver

.Beaver evidence at Mirror Lake.

 

Nature Scene, Yosemite Valley, BW




4 Comments Comments Icon

  1. Sherry Guzzi - Tahoe City, CA
    December 16, 2013 at 01:10

    Yes, the research cited by Dave shows beavers are native to the high Sierra, a their dams and ponds create wetlands valuable for all wildlife, as well as slowing erosion and replenishing the water table.

  2. Sherry Guzzi - Tahoe City, CA
    December 16, 2013 at 01:10

    Yes, the research cited by Dave shows beavers are native to the high Sierra, a their dams and ponds create wetlands valuable for all wildlife, as well as slowing erosion and replenishing the water table.

  3. Sherry Guzzi - Tahoe City, CA
    December 16, 2013 at 01:10

    Yes, the research cited by Dave shows beavers are native to the high Sierra, a their dams and ponds create wetlands valuable for all wildlife, as well as slowing erosion and replenishing the water table.

  4. Dave - Mariposa, CA
    December 14, 2013 at 11:27

    Beaver are actually native to the Sierra see link, their populations are expanding for the better, we need to stop perpetuating the non-native nuisance myth in the Sierra http://oaecwater.org/sites/oaecwater.org/files/Lanman-et.-al-2012.pdf

 

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Did You Know?

Tuolumne River

In 1984, 83 miles of the Tuolumne River were added to the Wild and Scenic Rivers System by Congress with an amendment to the Wild and Scenic Rivers Act. This included 54 miles of the river within Yosemite National Park.