Beneficial animals Harmful animals

The Beaver: Friend or Foe?

Cute in cartoons, rarely seen in the wild, our beloved beaver is a renowned landscape architect. It’s one of the few species to modify nature to such an extent: it can transform a forest into a wetland, or even a lake, in just a few weeks… Which sometimes attracts the wrath of landowners…!

The only other species that modifies nature so much… is us, human beings.

Photo: Te lensFix

Before I explain why the beaver is such an essential part of our environment, I’d like to tell you three things:

If a family of beavers has moved into your home and is causing you problems

Please don’t write in the comments that they all deserve to die or any other aggressive, negative opinions like that. Yes, you’ve had a bad experience, I understand… but I want to have a nice day and dead beavers make me sad!

There are solutions other than illegally hunting these large rodents, and I’ll tell you about them at the end of this article. If you’ve stumbled across this page in search of solutions and you’re not interested in the animal and the balance it creates, I invite you to jump immediately to the end of the article to the “Dislodging the troublemakers” section.

Photo: Andrew Patrick

If you are from a European city

I know that Canada is perceived as a wild place where we ride caribou with a fur hat and a raccoon friend on our shoulder, but… the truth is that those days are long gone. We’ve had wifi and McDonald’s for a few years now, I know, it’s incredible!

Well, I’m making fun of it, but I was asked if I had a pet beaver the last time I was in Paris…

The reality is that many Canadians have never seen a beaver, since they live in natural environments, not in cities like skunks and squirrels sometimes do. And even if they don’t scavenge, beavers are unfortunately often perceived as pests. Which is ironic, given that they’ve been Canada’s national emblem since 1975!

If you’re a Canadian proud of YOUR beaver

The Castor canadensis species can be found across much of North America, as far north as Mexico! It has even been introduced into Europe, where it competes with Castor fiber, another beaver species native to Eurasia. Although this article is about canadensis, the two species are very similar.

The Beaver at a Glance

I don’t want to bore you with facts unrelated to gardening, but it really is a fascinating animal and, before we get to the “hot topic” (I’m talking about flooding), let me introduce you to our friend the beaver…

  • It’s the world’s second-largest rodent, after the capybara found in South America.
Photo: Noe De Angelis
  • It feeds mainly on bark, but also on a few branches and foliage.
  • It cuts a trunk about 20 cm (eight inches) in diameter in three or four hours. For a two-metre-high sapling, it’s more like… 5 minutes! He then drags the tree to his dam to solidify it, and feeds on the young branches.
Photo: Derek Otway

Lodge or Dam?

  • We often confuse the dam with the lodge: the beaver doesn’t live in the dam. Its home, the lodge, is built like the dam, with mud and wood, and is upstream from the dam, where the water is deeper. A second, smaller lodge, or simple underwater pile, serves as its larder.
The lodge. Photo: srall
  • It’s important for the entrances to their lodge to be submerged, to protect them from predators and bad weather: that’s why they sometimes build a dam to raise the water level and hide the entrances to his house. In a way, water is… the door! This is also why we don’t see them in winter: even if they’re not hibernating, they goes under the ice to draw on their reserves, and return to the hut to feed themselves in the dry.
Photo: Schmiebel

Fur, Tail and Cousin

  • Its fur is made up of two types of hair: a very dense, warm one called the “fluff”, and longer hairs called the “topcoat”, which are made waterproof by an oil it produces and spreads over its body.
  • Its flat tail serves several purposes: to flatten the mud for the dam, to steer it as it swims and, above all, to warn of danger. To do this, it strikes a sharp blow on the surface of the water with its tail, making a loud noise and warning the whole family.
  • The coypu is a South American species that bears a striking resemblance to the beaver. But they’re not really related: the beaver is the cousin of kangaroo mice, while the coypu is closer to guinea pigs, chinchillas and porcupines. The coypu is an invasive species that has spread just about everywhere: North America, Europe (where it is a problematic invasive species), Asia and East Africa. There are none in colder regions, since frost is fatal to them, and they live in burrows rather than dams. Apart from the fact that its tail is not flat, the physical resemblance with the beaver is nevertheless quite surprising!
Coypu. Photo: Gzen92

An Architect Who Creates Life

“Well, Audrey, aren’t you laying it on a little thick?”

In fact, we’re not far off! By creating a dam, the beaver creates a whole new environment. Where there was once a small stream with a few frogs, a pond, a lake or even a peat bog can be created following the installation of Mr. Rodent. Other species then arrive to take advantage of this new environment: fish, birds, turtles, invertebrates and so on.

It may seem trivial, but if the environment becomes suitable for a new prey, such as snails or crayfish, the place becomes very interesting for a variety of other species. Where once there were only green frogs, there are now kingfishers, sockeye salmon, Blanding’s turtles, muskrats… all because a beaver moved in!

Blanding’s turtles are strongly associated with beaver dams.
It’s an endangered species, and unauthorized dam removal can kill turtles, especially in winter, when they no longer have enough water to hibernate. This is just one example out of dozens!

A Little Beaver in Your Pancakes?

Although beaver hunting is rarely practiced today, it still exists. Training and a permit are required for trapping. Some 8,000 people in Quebec engage in this activity every year. Legal trapping is humane and necessary for the balance of ecosystems. You read that right: necessary! With the arrival of humans, many natural predators have deserted their habitats, and without hunting and trapping, many species become overpopulated, upsetting the fragile balance of the environment. By hunting, humans play the role of predator.

So, what to do with a beaver? Without going into the details of traditional uses by First Nations, the three main uses are fur, meat and the glands near the anus that produce the famous oil that waterproofs their fur.

This oil, castoreum, is very important to us! But we don’t use it to waterproof things, no… we put it in our pancakes. Do we? Yes, that beaver oil is one of the ingredients in artificial vanilla flavor. Although it’s not really used on a large scale anymore because of its cost, it was widely used in the 1900s to flavor cakes and cigarettes. I wonder if beaver tails already contain castoreum?

Castoreum is still used in perfumery and traditional medicine. Many of the oil’s virtues have been recognized since ancient times. Studies have demonstrated its effectiveness in treating certain ailments, thanks to the salicylic acid it contains, a compound similar to aspirin.

Dislodging the Troublemakers

Hello again to our discouraged beaver readers! What should you do if a family has taken up residence in your home?

Photo: y_y

First of all, don’t be like my cousin (a cousin by marriage!) who decided to set fire to the dam on his land with gasoline. Firstly, it’s illegal, and secondly, it’s very dangerous. Luckily for him, his eyebrows grew back…

And don’t be like the hunters who use their firearms to kill beavers. It’s still illegal and dangerous, but what’s more, it’s pointless: the dam will always be there, and there’s a good chance another family will move in.

So destroy the dam? You’re cute, but the beavers will rebuild it, and probably faster than the time it took you to destroy it. They’re very, very hard to move: when they like a place, they stay.

So what can you do?

The Only Right Answer Is: Call a Professional!

There are permanent devices that will allow water to flow freely on either side of the dam. At worst, the beavers will leave on their own, seeing the futility of their efforts, and at best (in my opinion, eh!) they can choose to stay and live with the place. Then you’ll have some wonderful animals in your home, without flooding.

Fun fact: orange teeth are a sign of good health in many rodents! Photo: Denitsa Kireva

Contact your city’s or regions environment department, or a conservation organization. There are many ways to “repair” a waterway blocked by beavers: the Morency cube, the Leclerc triangle, and others.

Be aware that even if you pay taxes to the city, the land belongs first and foremost to nature. And there’s no point in getting angry with her! You’re bound to lose out anyway. Understanding nature and acting accordingly is the secret to good cohabitation.

Good luck with your neighbors and roommates of all kinds!

Audrey Martel is a biologist who graduated from the University of Montreal. After more than ten years in the field of scientific animation, notably for Parks Canada and the Granby Zoo, she joined Nature Conservancy of Canada to take up new challenges in scientific writing. She then moved into marketing and joined Leo Studio. Full of life and always up for a giggle, or the discovery of a new edible plant, she never abandoned her love for nature and writes articles for both Nature sauvage and the Laidback Gardener.

2 comments on “The Beaver: Friend or Foe?

  1. Christine Lemieux

    Years ago I saw (and heard!!) a beaver strike its tail as a warning. It is something I will never forget. Great article, very interesting!

  2. Beavers are actually common in and around Calgary, with the Bow and Elbow rivers running through. In a few areas, they are allowed to have dams/lodges.

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