Grade Levels

K - 10

Objectives

    Mystery stories are sometimes "who-done-its." Putting together evidence (clues) to identify the perpetrator is fun. It can also be part of a scientific approach to problem solving. This activity focuses on actual clues left behind by various animal suspects. From this evidence, students make inferences about both the perpetrators and the circumstances under which the clues were left.

Students will investigate interrelationships between animals and their environment by:

• observing clues to wildlife activities;
• inferring about the types of wildlife present in an area and their activities.

Standards of Learning

Science:

• Kindergarten: K.1
• Grade One: 1.1, 1.5
• Grade Two: 2.1, 2.4, 2.5, 2.7
• Grade Three: 3.1, 3.4, 3.5, 3.6, 3.8, 3.10
• Grade Four: 4.1, 4.5
• Grade Five: 5.1, 5.5
• Grade Six: 6.1, 6.2, 6.9
• Life Science: LS.1, LS.4, LS.10

Background

    The prospect of a class trip to a state park or other natural setting may inspire students to envision scenes from National Geographic specials or Disney nature films: A cotton-tailed rabbit dashing into a thicket just beyond the grasp of a swooping red-tailed hawk, a beaver gnawing down a birch sapling, an otter in hot pursuit of a bluegill, or a gang of wild turkeys scratching about on the forest floor for beech nuts and beetle grubs. All are very real scenes, happening daily in state parks but seldom witnessed, and especially not by crowds of enthusiastic youngsters. However, all animals leave behind clues of their activities--what they've been eating, where they've been walking, running, resting and rearing their young, When 15 to 30 pairs of eyes, start searching an area for these signs, fascinating--and wonderfully gross!--discoveries are sure to follow.

    Tracks, among the most obvious clues of an animal's presence, are most easily found in mud or sand near puddles, ponds or waterways. Each type of animal leaves a distinct footprint, distinguished by the number of toes, claw marks, size and arrangement of the tracks.

    Marks left by feet are not always very distinctive but they may still be important clues. For example, claw marks on smooth bark indicate where squirrels, opossums or raccoons have been climbing. Narrow trails or pathways indicate the regular routes of deer, rabbits or raccoons. A worn place on the bank of a creek or pond might be where beavers or otters regularly come ashore. Miniature tunnels through thick grasses are used by shrews, mice and voles. Small, soft ridges in the soil mark the tunnels of moles.

    Animals leave an abundance of evidence of what and where they have been eating. Deer and other browsers snip off tips of twigs and branches. Squirrels drop stripped pine cones and nut shell fragments. Small, freshly overturned patches of leaves and soil might indicate where a squirrel has stashed or recovered nuts. Large patches of overturned leaves might be where a gang of turkeys have been foraging. Scattered feathers or tufts of fur show where a predator captured a bird or mammal.

    The form and contents of droppings, or scat, can reveal a lot about the types of animals living in an area and what they've been eating. The scat of Virginia's native plant eating animals tends to be small and uniform in size and composition. Scat of carnivores and omnivores tend to be larger and may contain hair, bones, and undigested seeds.

    Not everything that looks like a dropping is necessarily scat, however. Among birds of prey, such as owls, not all of the undigestible parts of a meal pass through the digestive tract. Instead, these birds regurgitate pellets of fur and bones, about the size of the end of a thumb, which often accumulate under a favorite roost.

    Roosts of other birds might be recognized by white splatters from their droppings on the ground under trees. Other signs of animal resting places may be compressed vegetation in a thicket where deer have been resting, or a few hairs clinging to the bark just outside a hole in a tree where a squirrel or raccoon has been entering and exiting with regularity.

    Many animals, especially birds, build nests when they're ready to raise young. Although most nests in an area will be well hidden, a few can usually be spotted. Song birds' nests are typically tucked away in thickets or in the leafy cover of trees, and may be constructed of an infinite variety of materials including grasses, spider webs, straw hair and strips of bark. Large birds of prey, such as red-tailed hawks and bald eagles, build nests of sticks high in the trees tops. Woodpeckers excavate holes in dead trees or limbs and nest within the hollow.

    Some animal homes may be used year-round, such as squirrels' large leafy nests near the tops of trees. Beaver lodges constructed of mud, branches and vegetation may be conspicuous. A smaller wetland resident, the muskrat, constructs a similar, but smaller lodge from mud and grasses.

Materials

• orange or red ribbon or flagging tape (two 1-foot pieces per student)
• ice cream sticks or short dowel rods (2 or more per student)
• copy of questions (1 per team)
• clip boards, paper and pencils (optional)
• plaster of Paris (optional)

Resources

Byrd, N. A. 1981.

A Forester's Guide to Observing Wildlife Use of Forest Habitat in the South. U.S. Dept. of Agriculture, Forest Service.

Smith, R. P. 1982.

Animal Tracks and Signs of North America.. Stackpole Books, Harrisburg, PA.

Stokes, D. and L. 1986.

A Guide to Animal Tracking and Behavior. Little, Brown and Co., Boston.

Procedure

Before the Trip:

1. Visit the park and select the best site or sites for this activity. Areas with plenty of diversity and with a little mud or sand are best, but the activity should work just about anywhere.

2. Describe to the class what the area of the park to be visited looks like.

3. With the class, brainstorm about the types of animals that might live in that part of the park and clues that those animals might leave behind. Write ideas on the board.

4. Divide the class into teams of three. Each team makes a set of six flags out of foot-long pieces of bright orange or red ribbon, taped to ice cream sticks. (Any thin, but not sharp or splintery, stick will do, as long as it can be pushed into the earth.)

5. Explain to the class that they will look for animal clues at the park and mark the clues with the flags.

6. After the search time has elapsed, each team will lead the rest of the class on a tour of its site. Each team member will talk about two of the clues, giving their team's inferences about the set of questions provided.

7. Make a copy of the questions for each team to use during the activity.

At the Park:

1. Lead the class to the area designated for searches.

2. Distribute copies of the questions.

3. Define boundaries for each team, making them as large or small as necessary considering the age of the students and the diversity of the sites. Space chaperons so they can assist several teams.

4. Set a search time limit of 10-20 minutes. Each team searches within its designated area for six different kinds of animal clues. When a clue is found, it should be marked with a flag (either poked into the ground near it or tied to a branch).

5. As clues are found, team members should plan their answers to the set of questions.

6. Regroup the class. Tour each team's site, with team members pointing out and discussing their animal signs. (Team members should retrieve their flags at this time.) Encourage all students to share alternative explanations.

Extensions

1. Students use track field guides to identify the signs they found and verify their answers.

2. Make plaster-of-Paris casts of pet and people tracks found on the school grounds or at home.

Where in the Parks

When

Time Required at the Park:

1 hour, daylight hours.

Time of Year:

All seasons.

Variations

Younger students:   One chaperone per group will be necessary. Charperones should participate in the clue hunting with hints directing students to clues they might otherwise miss. Small groups of children could look for animal tracks. Pictures of different animal tracks could be shown and discussed before the trip.

Gifted/Advanced:   Students formulate a testable question and make a hypothesis about an animal behavior study that can be conducted at home or in the school yard (using birds, invertebrates, pets, etc.), design, and conduct the study.

• Whose Clues?