FOCUS: Muskrats and beavers are furry mammals that spend much of their lives in and around the water of streams, ponds, and wetlands. Both animals modify their habitat to suit their needs, and beavers in particular have a significant impact on their environment. Beavers and muskrats have many special adaptations for their largely aquatic lives.
INTRODUCTION
Objective: To begin to explore and ask questions about beavers and muskrats.
Give small groups of children several photographs of beavers and muskrats to examine and sort.
Materials an assortment of photographs of beavers and muskrats.
BEAVERS AND MUSKRATS UP CLOSE
Objective: To examine and compare beaver and muskrat skulls and pelts and to consider how their special adaptations function in their lives.
In small groups, give children a chance to hold and study different beaver and muskrat skulls and pelts. Use the Beaver Kit Study Guide questions to help children think about each part and how it relates to a beaver’s or muskrat’s life.
Consider the following topics:
Skulls
- Compare the size (length, weight, thickness of bones) of the two skulls. Which is a beaver? Which is a muskrat? (Beaver is much bigger than muskrat.)
- What do they notice about the location of the eyes and how might this be related to life in a pond? (Eyes near top of head to look out for predators while swimming.)
- What do they notice about the front teeth? (Bright orange incisors, chisel-like, sharp.)
- How would these be important? (Gnawing through wood, chipping or scraping off bark.)
- Measure the width of a beaver and muskrat incisor. Compare the tooth marks on the sticks with the size of the incisors on beaver and muskrat skulls.
- Which animal made these teeth marks? (Beaver.)
- How would the wide, rough molars help with the diet? (Grinding up tough woody vegetation.)
- Notice the space (diastema) behind the incisors. How might this be helpful? (Carrying sticks; lips close behind front teeth for gathering food under water and to keep chips out.)
Pelts
- Compare the beaver and muskrat pelts. What are some differences? (Color, thickness, texture.) How would this fur help animals that live in water? (Thick fuzzy undercoat is warm, sleek upper coat sheds water.)
- Why would beavers and muskrats spread oil on their fur? (For waterproofing.)
- A beaver’s front teeth can grow up to four feet in a single year! Use the four-foot string to see how long this is.
- What are some questions the children have about beavers or muskrats?
String
- A beaver’s front teeth can grow up to four feet in a single year! Use the four-foot string to see how long this is.
Materials: Beaver Set: beaver and muskrat skulls and pelts from a licensed owner, beaver-gnawed sticks, and wood chips; four-foot string, magnifying lenses, ruler, Beaver and Muskrat Set Study Guide and Key.
BEING A BEAVER
Objective: To model and experience two activities important in the lives of beavers.
Fell a Carrot: Have each child hold the widest end of a carrot on a table or bench so that it stands upright, or children can lie on a tarpaulin to chew down their carrots. Have the children tilt their heads at an angle, and at the command “go,” gnaw the carrot around the base until the top topples off. Have them call out “timber” when their carrot falls. Could students tell which way the carrot was going to fall? Can beavers?
Munch a Branch: Give each child a large, thick pretzel stick. Have the children hold the pretzel with the ends of their fingers as though eating corn on the cob and use their teeth to gnaw off the salt, the way beavers chew the bark off a branch. What parts of a tree do beavers eat? (Mostly the inner bark and young bark of twigs and small branches.)
Materials: for each child: a long carrot with top cut off, a thick pretzel stick, napkin; optional: tarpaulin.
BEAVER POND SEARCH and JOURNAL ACTIVITY
Objective: To explore a beaver pond, looking for evidence of beaver and muskrat activity.
Bring children to a beaver pond where they can look for signs of beaver and muskrat activity. Have the children work in small groups or pairs and look for the items listed below.
Beaver Pond Search
Beaver dam
Beaver lodge
Muskrat lodge
Water going under or over the dam (listen carefully)
Plants growing on the lodge or dam
Stick with bark chewed off
Old weathered beaver stick
Chewed stump
Partially cut tree
Beaver tooth marks
Pile of wood chips left by a beaver
Muskrat grass twist
Beaver scent mound
Beaver or muskrat canal
Beaver or muskrat tracks
Beaver or muskrat scat
Beaver or muskrat!
Have children pick one sign they find to draw in their journals. It could be a chewed stump or stick, the lodge, a print, etc. Have children gather in small groups with a leader and take turns sharing their discoveries and journal entries. Did the children find any evidence that there are beavers living in this pond today?
After classes are done visiting the pond, be sure to leave the area as it was before your visit.
Materials: Beaver Pond Search cards, journals or clipboards and paper, pencils; optional: colored pencils.
UPPER GRADES CHALLENGE: Mapping Beaver Pond Finds (Grades 5-6)
Objective: To look for evidence of beaver and muskrat activity at a pond and create a map of these discoveries.
Ahead of time print or draw a basic outline of the beaver pond and its surroundings. Make copies to bring to the pond, and a clean copy (or larger version) for the final map.
At the pond, have students work in small groups with a leader to explore different areas, looking for signs of beaver and muskrat as well as other animals. Students may find beaver canals, pathways, dam and lodge, gnawed stumps, beaver scent mounds, muskrat grass twists, otter slides, and tracks and scat of numerous animals. Give students a chance to view discoveries made by other teams as well as their own.
As each team surveys its section of the study area, have them enter their discoveries onto their map and then transfer these to the final map. Entries may be numbered points that refer to a list describing each find or to drawings and photographs that the students make at each discovery. The map may be shared with other school groups visiting the same pond or used as a baseline for comparison with findings in future years. What questions do they have about beavers or muskrats from their exploration of the beaver pond? Make a list of these and discuss whether any could be pursued with an investigation.
After classes are done visiting the pond, be sure to leave the area as it was before your visit.
Materials: For each small group: sketch or map of beaver pond to be studied, clipboard, pencils, drawing materials, track and sign guide; optional: camera, compass.
BEAVER WETLAND DIORAMAS
Objective: To make a model of a dam and lodge to understand the engineering skills of beavers.
Using the Beaver Lodge diagram to illustrate, discuss with children the design of a beaver lodge and how it functions. Have the children work in pairs, and give each team some craft dough, a paper plate or an oblong cardboard tray and some small sticks. Have the children build a dam and lodge on the tray, using layers of dough and sticks. The lodge should have an inner chamber and an exit tunnel. How does fresh air enter a beaver lodge and stale air get out? Children may wish to have their diorama “tested” to see if their dam holds water.
Materials: Beaver Lodge diagram, for each team: play dough*, handful of twigs, paper plate, cardboard tray; optional: pitcher or jug of water.
*Play dough recipe with flour and salt: Mix 2 cups flour, 1 cup salt, 4 tsp. cream of tartar, 2 tbsp. vegetable oil, and 2 cups water in a saucepan. For gluten-free, substitute 1 cup rice flour and 1 cup cornstarch for the 2 cups flour. For brown dough, add ¼ cup instant coffee to water.
Mix all ingredients in saucepan and cook over medium heat, stirring constantly. Cook about ten minutes, until it’s like mashed potatoes. Turn out on a plate, cover with damp cloth, and let cool. Knead until smooth, then store in airtight container.
DRESS A BEAVER, DRESS A MUSKRAT
Objective: To use a model to compare beaver and muskrat adaptations.
Ask a willing volunteer to stand before the group and be dressed up as a beaver. Using questions such as those below, discuss the beaver’s many adaptations. As you discuss the role of each of the following adaptations, add a funny prop to the costume. Muskrats have many similar adaptations as illustrated in the Beaver and Muskrat Adaptations sheet, which you may mention as you dress the beaver model. Or you may also dress a willing child as a muskrat, talking about how they are smaller and how their adaptations compare, using costume materials as noted below:
What special adaptation do beavers have that helps them to…
- Stay warm and have dry skin when swimming? (Fur vest or jacket.)
- Swim for ½ mile and stay under water for 15 minutes without coming up for air? (Picture of lungs, balloon or bean bag for liver.)
- Swim fast while hauling a big log? (Swim fins or large work gloves to put on feet.)
- Waterproof its fur? (Small bottle or can of oil.)
- Comb its fur? (Comb.)
- Pick wood chips from its teeth? (Tweezers.)
- Keep teeth sharpened? (A stick.)
- Gnaw while under water? (Illustration showing lips closed behind teeth.)
- Keep water out of ears and nose? (Nose plug, ear plugs or cotton balls.)
- See underwater? (Swim goggles or regular glasses.)
- Steer, make noise, store fat, use as a prop? (Canoe paddle or cardboard tail.)
- Cut down trees? (Orange paper strips for teeth.)
What special adaptations do muskrats have that help them to…
- Stay warm and have dry skin? (Fur vest.)
- Keep fur waterproof? (Small bottle or can of oil.)
- Stay underwater for a long time without breathing? (Small-size lungs cut-out.)
- Swim fast? (Small swim fins.)
- Keep teeth sharpened? (Piece of a cattail.)
- Gnaw while under water? (Illustration showing lips closed behind teeth.)
- Steer and make noise? (Felt or paper)
- Cut off cattails and other tough vegetation? (orange paper strips for teeth)
Give your costumed beaver (and muskrat) a round of applause!
*Optional: give every child in the class a set of orange paper beaver teeth and have them pose for a group photo.
Materials: Fur vest or other fur clothing; Lung Cutouts for muskrat and beaver, balloon or beanbag; swim flippers or large work gloves; small bottles or cans of oil; comb; tweezers; orange paper strips for teeth; stick, preferably gnawed; illustration of beaver lips closed behind front teeth; ear plugs or cotton balls; nose plug; swim goggles or glasses; canoe paddle or cardboard beaver tail. For dressing a muskrat: fur vest, small-size picture of lungs, small swim flippers, small bottle or can of oil, orange paper rectangles for teeth, muskrat tail of paper or felt. Optional: Beaver and Muskrat Adaptations sheet, orange paper teeth for everyone in the group, camera.
PUPPET SHOW “The Tales of Two Rodents”
Objective: To compare beaver and muskrat behavior and adaptations.
Perform the puppet show, or have a group of children perform it for the class. Afterward, ask questions to review the key details and vocabulary in the story. Why does a beaver build a dam and a lodge? (To make a pond so lodge can be surrounded by water for safety.) How does it get food in winter? (Underwater entrance, food stored in bottom of pond.) Why is it warm inside the lodge? (Body heat from family of beavers.) What are some similarities between beavers and muskrats? (Swim, waterproof fur, gnawing teeth, carry sticks, beady eyes, build a lodge.) Differences? (Size, tail shape.)
Materials: puppets, script, props – three or four small sticks, wood blocks to clap, stage.
SLIDE SHOW
Objective: To view photos of beavers and muskrats, their habitat, special adaptations, lodges and other signs of their activity.
Show slides or pictures of beavers and muskrats, beaver ponds, beaver dams, beaver and muskrat lodges, food caches, gnawed logs, stumps, and wood chip piles. How do beavers and muskrats change the environment in which they live?
Materials: beaver and muskrat slides and script, projector, screen.
CLOSING THOUGHTS
Objective: To reflect on new discoveries about beavers and muskrats.
Gather children into a circle and have each child complete the sentence, “One special thing I learned about beavers or muskrats is…” or “Once I saw a beaver and…”
A STEP BEYOND
Family Excursion to Beaver Pond: Have children take their families to a nearby beaver pond to explore it together. Visit again at different time of the day or night and make note of beaver and muskrat activity.
Muskrat and Beaver Poster: Have children make a poster comparing beaver and muskrat adaptations.
Beaver Baffles: Sometimes beavers live where they are not wanted. Have children talk with game wardens or animal control officers to learn ways to help beavers and humans coexist.
Building Dams: On a hot day, encourage children to try to build their own dams across a small stream. Be sure to dismantle them afterward.
Nearby Nature 