© 2013 FreeTiiuPix.com NATURE’S ENGINEER - THE BUSY BEAVER Our Natural World NATURE’S ENGINEER...

© 2013 FreeTiiuPix.com NATURE’S ENGINEER - THE BUSY BEAVERNATURE’S ENGINEER - THE BUSY BEAVEROur Natural WorldOur Natural World

Our Natural World

NATURE’S ENGINEER THE BUSY BEAVER

This slide show courtesy of FreeTiiuPix.comFree educational resources photographed & written by Tiiu Roiser BAA, BEd. & Kevin Chorowiec OCT, BAS, BEd.

© 2013 FreeTiiuPix.com

Our Natural World

NATURE’S ENGINEER THE BUSY BEAVER


Beavers are Mammals in the Rodentia Order in the Castoridae Family. They are semi-aquatic rodents who are primarily active at night.

Toronto Zoo North American Beaver


Beavers build “lodges” or homes out of sticks, twigs, rocks and mud. Beavers often burrow into the banks of rivers and lakes. They will also turn less suitable habitat into artificial ponds by building dams to block streams and rivers.

Northern Ontario


Beavers gnaw and fell trees to create log, branch and mud structures to block water flow. They change the landscape for their own purposes to create large ponds.


Since beavers do not hibernate during the winter, their lodges need to be built in deep water so that the underwater entrance does not freeze in the winter.

Beaver Lodge


Beaver ponds provide habitats for birds that would otherwise not live in these areas.

Heron with prey – Northern Ontario


Beaver ponds also encourage the growth of water-loving plants that thrive around the pond. Here we see Duckweed, Water Lilies and Pickerel Weed.


Pickerel Weed and Typha


A beaver’s fur is naturally oily and waterproof. Notice the reddish brown of the beaver’s coat? A beaver further waterproofs its fur by coating it with castoreum – an oily secretion from its scent glands.

Toronto Zoo Beaver


A beaver’s tail is broad and rounded. It is covered with large blackish scales.

Beavers use their tails in three ways:

- as a prop to help them sit or stand;

- as a rudder for swimming; and

- to slap the water to warn others of danger.

Toronto Zoo Beaver


On land, beavers move with a waddle, rocking left to right.

In the water they are very graceful, strong swimmers that swim at speeds of up to five miles (8 kilometres) an hour.

Toronto Zoo Beaver


Did you know…

that only the hind feet of a beaver are webbed and that beavers have transparent eyelids that function like goggles !

Toronto Zoo Beaver


Although usually active at night, this busy beaver was hard at work in the middle of the day.

Grundy Lake Provincial Park - Ontario


This beaver lodge was built at the edge of a lake.Grundy Lake Provincial Park, Swan Lake - Ontario


Beavers cover their lodges with fresh mud. This freezes in the late autumn and becomes as hard as cement and prevents predators such as wolves from penetrating it. The entrance to the lodge is under the water.

Grundy Lake Provincial Park, Swan Lake - Ontario


Beavers have a pair of scent glands, called castors, with which they secrete a musk-like substance called castoreum to mark their territory. Look carefully around beaver ponds and you will find mounds of mud and vegetation marked by the substance.


The entrance to the beaver lodge is via an underground tunnel under the surface of the water. The fresh branches with young, tasty leaves have been accumulated as a food source although beavers also like to eat bark, twigs, roots and aquatic plants.


Trenches, ditches or “runs” are flooded passageways that the beaver uses to move in and out of the water. This lodge was surrounded by flooded ditches that ran through the surrounding bushes. The ditches give the beaver cover when moving about.


Beaver’s fell trees to build their dams and lodges, but eat smaller trees and their branches for their yummy new growth.


Beaver use their front incisors (teeth) to cut through trees of all sizes. Their teeth grow continuously and a beaver in captivity that is not chewing will soon be in need of a dentist.


The outer edge of a beaver’s incisor has a very hard enamel. The inside edge is however much softer and will wear away much faster. This fact keeps the biting edge very sharp.

While the teeth of people and other animals wear away and become dull, this is not so with the beaver. They have teeth that are self-sharpening!


In addition to being great engineers, beavers know exactly which side of the tree to chew in order to get a tree to fall exactly where they want it to go.

In this image, the beaver dropped the tree toward the lake.


Since the beaver could not drag the large tree he cut down, he chewed the tree into manageable pieces. Note the piles of wood chips every 4-5 feet.


Beaver’s are prolific builders who can rebuild a dam overnight.

Northern Ontario


Beaver populations are declining because their building often interferes with the human population.

A beaver’s building habit results in the harvesting of trees and the flooding of land used by humans for roads.


This lodge was built in the middle of a swamp. A beaver built a dam in the drainage tunnels of a nearby road. Road workers broke the dam, the beaver rebuilt it. This cycle of building & destruction went on the entire summer.


A beaver at the Toronto Zoo turns his attention to the metal pole of a bird feeder – so strong is his instinct to chew.

Toronto Zoo Beaver


Toronto Zoo Beaver


- beavers mate for life;

- a beaver can remain under the water for up to 15 minutes;

- beavers can close both their ears and nose;

- an adult beaver is about 3 feet long and can weigh between 30 – 70 pounds;

- female beavers of the same age are larger than male beavers;

- baby beavers are called “kits”;

Fun Beaver Facts….

- kits are born with their teeth already exposed;

- a beaver in its 2nd year of life is called a “yearling”;

- beavers live in colonies made of an adult male and female and 2-4 kits;

Toronto Zoo Beaver


This slide show presentation courtesy of FreeTiiuPix.com. Free educational resources photographed & written by Tiiu Roiser, BAA, BEd. & Kevin Chorowiec OCT, BAS, BEd.

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Sources: http://www.beaversww.org/ http://animals.nationalgeographic.com/animals/mammals/beaver.html

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© 2013 FreeTiiuPix.com NATURE’S ENGINEER - THE BUSY BEAVER Our Natural World NATURE’S ENGINEER...

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