Depending on your point of view, the beaver is a nuisance rodent that destroys property or a charming woodland creature that combats global warming.
Beavers build dams, canals and lodges, and they rank among the few creatures that alter their environment. They can carry their weight – up to 30 pounds – in lumber, and they can stay underwater for 15 minutes. Beavers have orange teeth that can fell a five-inch willow sapling in six minutes. The average beaver cuts down 216 trees every year, which is why some people hate them.
But whether you come from a pro- or anti-beaver viewpoint, there’s no disputing the beaver’s historical importance. The critter played a huge role in the European colonization of North America. Yes, some of the Europeans came for religious freedom, but they also wanted to make some money. They crossed the Atlantic in the hope of cashing in on three kinds of natural resources: fish, forestry products and fur. Mostly beaver fur.
Here, then, are six fun facts about the beaver.
-
Beavers nearly disappeared from New England for a long time.
When the Europeans first arrived, there may have been as many as 400 million beaver in North America. By 1900, that number dwindled to about 100,000, and they’d been gone from the Northeast by the late 18th century. Over-trapping and clearcutting forests did them in.
The effort to bring them back started in New York state.
In 1904, the New York Legislature passed a resolution to reintroduce the beaver. According to Ben Goldfarb, author of Eager: The Surprising, Secret Life of Beavers and Why They Matter, beavers were hard to find. So New York state biologists went to a fair in St. Louis, the celebration of the 100th anniversary of the Louisiana Purchase. Canadians had brought beavers to put on display. The New Yorkers bought seven from the Canadian delegation and took them home. They also got a few from Yellowstone National Park. The eager beavers procreated to the point that 10 years later New York had a population of 15,000. Beavers then began to spread to Massachusetts, Connecticut and Vermont.
In 1914, Connecticut game wardens ordered two beavers shipped from Oregon and released them in Union. Massachusetts and Vermont followed in the 1930s. The population rebounded, helped along by the many abandoned farms that had gone back to forest.
It’s hard to understand what he was thinking, but George Dorr tried to reintroduce just one beaver to Acadia National Park, which he supervised. It didn’t survive. The next year he introduced three and they multiplied.
-
The Plymouth colonists traded beaver.
They needed to repay their creditors who had financed the settlement, and they could do it with beaver pelts.
Beaver fur is different than that of other species because it has a soft underfur, called beaver wool or duvet, beneath its coarse guard hair. Europeans loved beaver fur because duvet made great hats: Top hats, bicorns, tricorns, shakos, clerical, Wellington and beaverkins for children, to name a few. But demand for beaver fur in Europe had nearly extinguished the animal on the continent.
To make a hat, European hatters plucked the long guard hair to get to the duvet. They preferred beaver pelts with the long hair missing already because it made less work. The Wampanoag, on the other hand, preferred their beaver with the guard hair that kept them warm. So the Plymouth colonists traded their manufactured goods, like metal pots and finished pants, to the natives in exchange for pelts.
-
People once thought beavers chewed off their testicles and threw them at hunters to escape.
The reason: hunters also prized beavers for their castoreum, a yellowish, granular substance produced in the castor sacs near the beaver tails. The ancient Greeks and Romans used castor as medicine, for migraines, epilepsy, constipation, rheumatism and insanity. Perfume makers still use it in Shalimar and Chanel No. 5, distillers use it in high-end spirits and food manufacturers use it in Twizzlers and raspberry Jell-O.
The beavers have their own use for castor: They communicate with it. They don’t see too well, but they can smell. They spray a mixture of castor and urine onto small piles of mud to mark their territory and, in the case of single males and females, to signal their availability for romance.
-
The beaver helped start the environmental movement.
The decline of beaver and thus wetlands came to the attention of George Perkins Marsh, a Vermont farmer-turned-congressman. He is credited with helping to start the environmental movement. He described how wetlands shrunk in North America because of the fashion for beaver hats. No beaver, no dams, no wetlands. Then the wetlands began to expand when people traded in their beaver hats for silk.
In 1864, Marsh wrote a book, now largely forgotten, Man and Nature, or Physical geography as modified by human action. Modern environmental historians compare it with Darwin’s On the Origin of the Species.
“It takes a real act of historical imagination to understand just how profoundly Man and Nature reshaped American attitudes toward the environment,” wrote environmental historian William Cronon.
Man and Nature led to passage of the 1873 Timber Culture Act, which encouraged homesteaders on the Great Plains to plant trees. It laid the groundwork for the creation of Adirondack Park and the Forest Reserve Act of 1891. It also had a profound influence on environmentalists such as John Muir and Gifford Pinchot.
-
Naturalists view beavers as North America’s keystone animal.
Other species depend on beavers to create an ecosystem in which they can thrive. When beavers build dams and lodges, they create a watery home for many kinds of plants and animals.
For example, trumpeter swans nest on beaver lodges, which offer protection from predators and closeness to aquatic plants they eat. Beavers share their lodges with muskrats, too — that extra species helps keep it warm in winter.
Beaver ponds help humans, too. They put out wildfires and control floods. In the spring they store rain and snowmelt and release them slowly through the summer. The weight of beaver ponds presses water into the aquifer. After a beaver abandons the dam, the water drains out, leaving rich soil ideal for farming.
-
Beavers can build a watertight dam in a day.
Their lodges take a little longer, perhaps a few days.
To build, they carry mud, moss and sticks in their dexterous forepaws and propel themselves underwater with webbed hind feet carrying wood in their mouths. They use their leathery, scaly tails as a prop while chewing trees, as a rudder while swimming underwater and, with a quick slap, as a warning signal above the surface.
Beavers build the dams to create watery, therefore safe, surroundings for their lodges. Usually a family of four-to eight beavers lives in a lodge. The lodges get so hot inside that snow melts on top of them. Beavers build underwater entrances for safety. Beavers are monogamous, and usually keep their kits with them in the lodge for a couple of years.
Images: Frontal photograph of beaver By Bering Land Bridge National Preserve – Beaver- Steve Hersey edit, CC BY-SA 2.0, https://commons.wikimedia.org/w/index.php?curid=44326240. Drawing of beaver with kit Bull, Charles Livingston, Artist. Beaver With Baby Beaver. , None. [Between 1890 and 1932] Photograph. https://www.loc.gov/item/2010715272/. Beaver lodge By DrStew82 – Own work, CC BY-SA 4.0, https://commons.wikimedia.org/w/index.php?curid=60961377. This story last updated in 2024.