Why is a rodent on our state flag?

The rodent on the Oregon State flag is an American Beaver. In 1969, the Legislature recognized the American Beaver by naming it Oregon’s state mammal. Beavers enhance habitat for many other fish and wildlife species through dam-building activities. Beaver ponds provide areas for people to fish, hunt and view wildlife.

How did beavers earn this honor?

During the 1800s, beavers and several other fur-bearing animals were trapped and killed for their pelts or fur. Pelts were shipped back east, to Europe, and China to make beaver hats and coats.

Beaver pelts and activities played a significant role in helping to get Oregon’s economy and growth started. Some say that Oregon’s early economy was built on beaver pelts.

Beaver swimming (courtesy ODFW)

Unregulated trapping virtually eliminated beavers from many landscapes. Other animals trapped included mink, otters, muskrats, martins, raccoons, red fox, grey fox, bobcats, and other furs.


With proper management the beaver has become re-established. Beavers can be found in many state waters where the habitat needs are met. Beaver habitat almost always include riparian habitats with trees such as cottonwood and aspen, willow, alder and maple.

Small streams with a constant water flow that meander through relatively flat terrain in fertile valleys seem especially productive of beavers. Beavers can also be found near larger bodies of water such as lakes.

Well suited for water

Beavers are well suited for aquatic life with their paddle-shaped tail, webbed hind feet, compact body, and thick coat with coarse guard hairs that are coated with waterproof oils. Beavers also have a special membrane that cover their eyes and nose when swimming. Finally, Beavers are able to extend their time underwater (to at least 15 minutes) by slowing their heart rate.

Telling the difference

Beavers can be mistaken for muskrats or nutria. The tails and sizes of these animal are strikingly different.

Beavers are the largest rodent in North America often weighing in excess of 65 pounds, and may reach nearly four feet in length. The broad, flat paddle-shaped tail of the American beavers is nearly invisible when they are swimming.

Both muskrats and nutria are quite a bit smaller than beavers and very different tails. Muskrats and nutria have thinner tails and are significantly smaller. Nutrias typically range from 9-20 pounds and have a round tail. Muskrats have a thin, slightly flattened tail and can reach up to 4 pounds.

The tail of a Muskrat and Nutria will either sways back and forth like a propeller or are held out of the water as the animal swims. Nutria are considered invasive in many areas.

Clumsy on land

Courtesy Washington Dept. of Fish & Wildlife
photo by Laura Rogers

Beavers are at risk when foraging on shore or when migrating. Because of their size, behavior and habitat, adult beavers have few natural enemies. Predators include humans, bears, coyotes, bobcats, cougars, and dogs.

The beaver’s sharp incisors are used to cut trees and peel bark while eating. These incisors continually grow but are worn down by the grinding, tree cutting, and feeding. As the incisors wear down, the back surface is softer than the front which helps to create the sharp edge.

Beavers eat a variety of vegetation, roots, herbs, etc. Commonly consumed foods include hammer willows, vine and big leaf maples, alder, and cottonwood. In the winter, they depend on woody plants for most of their food.

Not all are dam builders

Beavers build deep water dams which helps deter predators, facilitates an underwater den entrance, and promotes growth of their favorite foods. Dams vary in size from a small accumulation of woody material to structures 10 feet high and 165 feet wide. 

These water areas help provide habitat for many fish and animals, and are critical to juvenile salmon.

But not all beavers build dams. Beavers living on lakes or large rivers that maintain a constant level do not build dams. They may still build lodges and bank dens for resting and rearing their young.

Beavers are also the mascot for Oregon State University.

–Oregon Dept. of Fish and Wildlife, Beavers (https://myodfw.com/wildlife-viewing/species/beavers, and Beaver factsheet (https://www.dfw.state.or.us/conservationstrategy/docs/Beaver_factsheet.pdf)
–The Oregon Encyclopedia, Fur Trade in Oregon Country gives a thorough account of the fur trade and economic impacts generated for the state (see https://oregonencyclopedia.org/articles/fur_trade_in_oregon_country/#.XtVBrW5Fycw