Busy Beavers

Busy Beavers

Beavers, the largest rodent, are nature’s engineers and are specially adapted for life in the water.

The Nature Friends program is for 4- or 5-year old children with an adult. The maximum group size is 20 child-adult teams. Programs are outside unless weather does not permit.

Pre-program activities

Touch fur. How is it different from a deer skin? Make tracks with beaver and other wetland critter feet.


The Pet Beaver


Can you name North America’s largest rodent? This animal is responsible for opening the West due to the demand for its fur in Europe. This animal is called nature’s engineer. Why do beavers build dams?

Activity: Beaver dress-up. (See Beaver Adaptations Sheet)


  • Goggles
  • Ear muffs
  • Clothes pin
  • Canoe paddle
  • Comb
  • Spray bottle
  • Raincoat
  • Plastic or paper cutouts of flippers

Use a beaver mount or puppet if it is available.
Ask for a volunteer. Have the volunteer put on the various items as you discuss the use for each.

Discuss the natural history of the beaver with the mount, pelt, and skull. Show photos of various lodges and how elaborate they are.

Craft options

1. Beaver Lodge

Build your own beaver lodge using sticks, mud or clay and pieces of cardboard to build on. Don’t forget to put a door in it!

2. Chisel and Stones Teeth

  • chisel
  • small twigs and leaves
  • wooden board
  • two flat stones
  • mirror
  1. Show the group the beaver’s skull. Then hold up the chisel. Ask children to notice the similarity between the illustration chisel. (Both have sharp, flat edges.)
  2. Place the twigs and leaves on the wooden board. Use the chisel to cut them. Explain that teeth like chisels are good for gnawing through wood and seeds.
  3. Show children the two flat stones and explain that the stones work the way a plant-eater’s back teeth work.
  4. Place some leaves (already chisel-cut) between the two stones and have children help grind them. Have children notice the way the leaves look when they are ready to be swallowed.
  5. Then have children feel the bottom of their own teeth. Let them look at their front teeth in a mirror. Ask: Do your front teeth look and feel like a chisel? (Yes) What kinds of food do your front teeth help you eat? (Vegetables and other foods that are gnawed)


Provide carrots or pretzel rods to be chewed on like they are twigs. Candy orange slices can be used as pretend beaver teeth.

Background Information

  • North America’s largest rodent.
  • Beavers are mammals: warm-blooded (body temperature remains about the same all the time, even if the temperature around them changes), live birth, mammary glands produce milk for their young, fur.
  • Active mainly at night (nocturnal), but may be active at dawn and dusk.
  • Herbivore (plant-eater). They especially like water lilies and tissue under the bark of trees.

Physical Appearance

  • The tail is wide, flat, and scaly. It is used to steer from side to side like a rudder, to go up and down when diving, as a brace to help it sit upright, (like a kickstand on a bike), or to warn of danger by slapping. The tail stores fat that the beaver can use if food becomes very scarce and regulates body temperature by passing heat into the water.
  • Thick brown fur.
  • Guard hairs, glossy outer coat.
  • Underfur, thick hair that water can’t pass through.

Life History

  • Mate for life.
  • Live up to 12 years.
  • 3 to 9 kits (babies) a year.
  • Kits are born in May after a three month gestation period.
  • Young stay with family until they are mature at age of two.


  • 60 million in North America before discovery of the New World.
  • During the 1600s, the demand for beaver pelts depleted the European beaver population.
  • By 1750, an estimated two million beaver had been harvested from North America.
  • The beaver population has returned to an estimated 612 million animals, due to stricter hunting laws.
Activities provided by:

Polk County Conservation Board
Lori Foresman-Kirpes
Nature Friends is funded by Polk County Conservation Board, West Des Moines Park and Recreation, and the Des Moines Chapter of the Izaak Walton League.

_ 0-1
_ 1-2
_ 2-3
_ 3-4
✓ 4-5
_ 5-6

Category: Adult-Child

Iowa Early Learning Standards:
8.1, 9.3, 11.1, 11.2, 12.3, 12.4, 12.5, 13.3, 14.3