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CRITTERS OF NORTH IDAHO: American beaver

Christian Ryan Correspondent | Hagadone News Network | UPDATED 5 years, 8 months AGO
by Christian Ryan Correspondent
| May 14, 2019 1:00 AM

photo

Ryan

Most animals are forced to adapt to their environment. When it gets cold and snowy, geese and other birds fly south for the winter. Wildebeest migrate across the African savannah to find fresh grazing. Groundhogs hibernate during the winter when food gets scarce. Humans are different in this regard because we can alter our environment to suit our needs, something very few animals can do. One of these animals is the beaver.

Beavers are quite more varied than many people think. Ice Age North America was home to the giant beaver, Castoroides ohioensis (give you one guess where it was first discovered!), and it grew up to 7 feet long and weighed between 170 and 276 pounds. That’s the size of an American black bear! Even further back in time, the grassy plains of Nebraska were home to Palaeocastor, a little species of beaver that lived in corkscrew-shaped burrows.

The American beaver (Castor canadensis) is the largest rodent in North America, and the second largest in the world (that title goes to the South American capybara). On average, they tip the scale at 35-65 pounds, but some specimens have been weighed at 110 pounds! From the tip of their buck-toothed snout to the end of their flat, scaly tail, these animals measure 3 to 4 feet in length. They are covered in thick dark brown to reddish-brown fur.

Distributed widely across the continent of North America, beavers usually inhabit rivers, lakes, ponds, marshes, streams and other wetland areas. They love to eat bark and the soft plant tissue underneath the bark called cambium — especially that of aspen, adler, birch, beech, maple, poplar and willow trees; with a side dish of cattails and other water plants, bulbs and roots. Most mammals are unable to digest cellulose, but beavers have a special brew of microorganisms in a sac between the large and small intestine called the cecum that do the job quite well.

Many mammals live in groups, but beavers take this to the next level. They live in family units consisting of a male and female, their current year’s offspring, and the offspring from the last two years who stick around to help take care of the rest of the family.

Unfortunately, there usually aren’t enough trees near the water’s edge to feed a family of hungry beavers, and their lack of defenses and speed on dry land make them an easy meal for wolves, bears, lynxes, fishers and wolverines. The beaver’s solution? Change the environment to better suit them!

A family of beavers gathers wood and mud together to build and maintain a dam that slows down the flow of the stream or river they find suitable to live in. This raises the water level, increasing the number of trees beavers can access and still be able to make a quick getaway should a land-bound predator show up.

Once the dam is complete, the beavers construct a dome-shaped, wooden structure called a lodge. Lodges are typically 6 and a half feet tall and can measure 39 feet wide! They are usually built away from the shore and can only be entered via one or two secret underwater entrances.

For a long time, we had no way of knowing what went on inside a beaver lodge, so the film crew for the 2004 BBC documentary “The Life of Mammals” was eager to be the first to find out. When a beaver family in Wyoming was away, the film crew sneaked inside to install a night-vision camera so they could see just what the rodents were up to!

Very little of the beaver’s lodge is used for living space. This is because the walls are very thick for the purpose of insulation. In fact, it gets so warm in a beaver lodge that heat can be seen rising from the top, even in winter! For this reason, beavers don’t have to hibernate like most rodents and can remain active all year round.

The BBC film crew observed the beavers making many trips from the lodge to where they had stored vegetation from the summer and autumn at the bottom of the lake. The frigid water acted like a freezer, preserving the food until the beavers were ready to eat it.

The film crew made another surprising discovery: a family of muskrats, a smaller semi-aquatic rodent, was sharing the lodge with the beavers! The muskrats would occasionally gather vegetation to add to the lodge’s bedding, and the beavers didn’t seem to mind sharing their food with them either.

Because of their great ingenuity, beavers are able to stay warm and cozy all winter long until the snow and ice melt. With the arrival of spring, the beaver construction projects continue!

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Christian Ryan can be reached at animaladventures1314@gmail.com

HOMESCHOOL PROJECT

HOW TO MAKE A BEAVER PUPPET

Puppets are fun for children of all ages! With these easy-to-follow instructions, this Beaver Puppet can be finished in no time.

MATERIALS:

2 White Sheets of Paper

2 Sheets Copper Felt

1 Sheet of Dark Brown Felt

White Felt

20mm Wiggle Eyes

Two 2-inch Beige Poms

1 inch Black Pom

Scissors

Pencil or Marker

Quick Dry Tacky Glue

Red Acrylic Paint

Wood Leaf

INSTRUCTIONS:

1a. Make two templates using the samples as a guide. Draw the tail “cut 1” on the sheet of paper. Cut out the template.

1b. Place your hand on the other sheet of paper and draw the beaver body “cut 2 inches around your hand. This is to insure that you have a more custom fit puppet. Cut out the template.

2. Trace the beaver template onto two sheets of cooper felt and cut out.

3. Stack the two beaver shapes together and glue along the top and side edges only.

4. Cut the tail, belly, paws and ears from the brown felt.

5. Glue on the eyes, two tan poms for the cheeks and the black pom for the nose.

6. Glue the top of the tail along the inside bottom edge of the puppet.

7. Glue on the ears, paws and the belly.

8. Cut a 1.5-inch square from white felt. Fold felt in half and cut a curve along the bottom folded edge to make teeth. Glue top edge under the cheeks.

9. Paint the leaf red. Allow to dry, then glue onto the belly.

If you have been finding these projects helpful please let us know. We would love your feedback.

•••

Project provided by Angel Dominiq

angeldominiq13@gmail.com

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