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Beaver
(Castor canadensis)
Photograph: U.S. Fish and Wildlife Service
Seasons in Walnut Creek: Year-round resident
Key Field Marks:
- Semi-aquatic rodent with webbed hind feet larger than front
- Second largest rodent in world, usually weighs 44 - 77 lbs
- Usually 2 feet long including tail, which is approximately 10 inches, large and wide
- Brown-black fur
Key Behaviors:
- Gnaws bases of trees until fallen, then gnaws limbs off the tree for food and shelter
- After eating will use peeled sticks to build "lodge" or "den"
- If startled, will dive under water and loudly slap the water with its tail to warn other beavers of danger
Habit and Range:
- Rivers, streams, and marshes throughout the U.S. and Canada; similar species in parts of Europe
- In a beaver dam, often free-standing in water, but sometimes built along banks in warmer climates
- Look for small to medium sized trees gnawed off cleanly at an angle or for tracks in soft sand near water
Walnut Creek Sighting: A beaver skull was found on the banks of Walnut Creek just east of Rock Quarry Road at the October Big Sweep cleanup.
This page prepared by 8th grader Lucas F.
Exploris Middle School - Spring 2008
