Beavers are our largest
rodents.
They have big bulky bodies, rounded heads, and small eyes
and ears.
Beavers have dark brown
fur and a large, flat, scaly tail. They also have large,
orange front teeth. Beavers' hind feet are black and
webbed.
These mammals can grow up
to four feet long and weigh 60 pounds.
Beavers can be found just
about anywhere there is water, including: marshes,
ponds, lakes, rivers, and streams.
Beavers are well-known for their construction. They build dams and lodges using sticks, branches, saplings, reeds, rocks, and mud. Dams can be forty feet long and ten feet high.
Lodges are dome-shaped homes, built up to six feet high. They have one or more underwater entrances, and a hollow area near the top where the Beavers live.
Beavers also make "scent mounds." Scent mounds are small one-foot tall piles of mud, sticks, sedges, and grass. Beavers leave their scent on the piles to mark their territory.
Copyright, Don Getty, California Academy of Sciences
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Beavers are active throughout the year, but are mostly nocturnal (most active at night).
Beavers are excellent swimmers and can stay underwater for 15 minutes at a time. They are able to close their nostrils and ears to keep water out. Their eyelids are clear so they can see underwater!
To construct lodges and dams, Beavers will take down trees. Usually they are small trees, but sometimes, especially if there aren't smaller trees around, they will take large ones.
To do this, the Beaver will use its large front teeth to bite chips off the trunk, while working its way around. Beavers' lips are behind the front teeth, so they can close their mouth while they work on a tree!
Once a tree has been felled, the Beaver will trim off the branches and drag/carry it to its construction site.
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Beavers don't just use
trees for building, they also eat them. Many of the same
tree species they take down for construction are used as
food. These include: willows, maples, hickories, Sweetgum,
American Beech, birches, and aspens. Beavers eat the bark
and soft wood just underneath the bark (called
cambium).
Other plants eaten by
Beaver include: pond lilies, sedges, pondweeds, algae,
ragweed, ferns, duckweed, Witch Hazel, and other shrubs,
weeds, and aquatic
plants.
Beaver prefer smaller
plants, rather than bark and wood from trees. They get their
food from trees mostly in the Winter when other plants
aren't available.
Beavers mate in late
January and February. Litters
of two to four are born in May and June. Young Beavers stay
with their parents for two years before they are forced to
leave.
Beavers mate for life,
and families work together to repair dams and lodges.
Families are very territorial
and slap their tails on water as a warning to other Beavers.
They also do this to sound an alarm.
Beavers do not have many
predators,
besides man, but they can be eaten by Red Fox, Coyote, and
Otter. Young Beavers are also caught by hawks and
owls.
Beavers are extremely
important to other wildlife. Their dams create
habitat
form many species of plants and animals, including: fish,
turtles, snakes, frogs, insects, herons, Osprey, eagles,
Belted Kingfishers, ducks, geese, otters, Raccoons, and
Muskrats.
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Copyright, Noecker Buick
Pontiac
When Beavers build a dam, it does
many things to the area around it. It makes places of deep and
shallow water, which helps fish. The many sticks and branches provide
good cover and shelter both above and below the water's surface.
Fish, frogs, snakes, turtles, and insects need this. The surface of
the dam is a good place for waterfowl, such as ducks and geese, to
build nests. It also provides good basking places for turtles and
snakes to get warm from the sun.
Birds and other animals that eat
fish, frogs, and insects are attracted to dam sites as good places to
feed.
When Beavers build a dam, it often
changes the course of the water. Places that were not previously
covered with water, now are, and this is habitat for water plants,
such as lilies, Lizard's Tail, and cattails. Places where water used
to be, but is no longer, have great soil for grasses, sedges, and
shrubs. This will attract deer, rabbits, and songbirds, as well as
many other animals. Eventually, these places will become
meadows,
and much later, forests.
Beavers also help trees
in places where they cut trees down. This might sound
strange, but it is true. Beavers have favorite species of
trees which they use. When they take them, other trees,
which aren't their favorites, are able to grow better
without competition.
American Elm is a tree that is not usually touched by
Beavers. Therefore, Beavers help elms when they cut down
competing trees, such as willows and hickories.
Beaver's also create
"runways" in marshes by traveling back and forth on the same
path. This makes a sort of underwater ditch, which turtles
and other animals use make their travel across the marsh
easier.
Humans have a love/hate
relationship with Beavers. For many years, Beavers have been hunted
and trapped for their fur. They were even eliminated from much of
their habitat in America. Today, they are doing much
better.
Even so, people get upset with
Beavers for the damage they cause to trees and with their dams. If
people live near water, and don't want to lose their trees, they
often have Beavers trapped or killed. This happened in nearby
Washington, D.C. when Beavers were using the famous cherry trees for
food.
Dams, since they change the shape
and course of water, can cause flooding. People who build their homes
too close to water get upset when Beavers build a dam which may flood
their property. This is one reason Virginia has passed laws to keep
people from building too close to water.
Overall, Beavers are
extremely helpful. They provide habitat for so
many important animals and plants, and help keep water healthy and
clean.
