Living in a Pond. Pre-Visit Lesson. Summary: Students will classify pond organisms into appropriate pond habitats and then draw it on a pond diagram.

Transcription

1 Living in a Pond Grade Level: 3-4 Teaching Methods: Analysis, Classification, Discussion, Drawing, Observation, Reading, Small Group Time: Preparation Time: 30 minutes Activity Time: 40 minutes Materials: Pond Diagram Large piece of paper or poster board Living in a Pond cards Pond Habitat Signs Card Stock Crayons or markers Pre-Visit Lesson Summary: Students will classify pond organisms into appropriate pond habitats and then draw it on a pond diagram. Objectives: Students will identify at least two areas of a pond where organisms are found. Students will draw a pond organism in the appropriate habitat location on a pond diagram. PA Environment & Ecology Standards: Watersheds and Wetlands A. Identify various types of water environments. C. Identify living things found in water environments Environmental Health C. Understand that the elements of natural systems are interdependent Ecosystems and their Interactions A. Understand that living things are dependent on nonliving things in the environment for survival Threatened, Endangered and Extinct Species A. Identify differences in living things. PA Science & Technology Standards: Biological Sciences A. Know the similarities and difference of living things. Other PA Standards: Reading, Writing, Speaking and Listening Arts and Humanities Background: A pond is a fairly small body of water that can be formed naturally or by damming water flow. When water flows downhill it gathers in depressions in the land. When these depressions are full, the water continues to flow out on the downhill side. By definition, ponds are shallow pools of standing water with a muddy, silty bottom that has plants growing from shore to shore. Commonwealth of Pennsylvania, Department of Conservation and Natural Resources, Bureau of State Parks 1

2 A pond has several distinct habitats: the edge, the surface, the open water, and the bottom. The water s edge is where the water meets the land. This area often has a variety of plants growing both in the water and on land. Surface tension is found on the top of the water and creates a skin-like barrier between the air and underlying water molecules. The water s surface is so strong that it can actually hold objects on top of the water. The water strider is a predatory insect that uses surface tension to skate across the top of the water looking for prey. Without surface tension this insect would sink. Open water is considered the deep part of the pond where aquatic animals, both large and small, can move freely. It is home to fish, turtles, frogs, and other animals. The bottom of the pond is a habitat that is home to a large number of organisms. Bacteria and other organisms help to decompose leaf letter and dead animals that fall to the bottom. Clams, mussels, crayfish, and worms can be found burrowed in the mud bottom. Getting Ready: Make a large cross section picture of a pond (see attached diagram.) Label the different areas found in the background information. Copy Living In A Pond cards and glue or paste them to index cards. You may want to laminate them for later use. Make Pond Habitat Signs. Write the name of each habitat (edge, bottom, surface, and open water) separately on a large piece of cardstock. Place in areas where small groups of students can gather. Activity: 1. Explain to the students that they will be visiting Presque Isle State Park to study a pond. Before they go on the trip you would like them to be familiar with some of the organisms (living things) that they may find. 2. Explain that ponds are small bodies of water that have a variety of plants and animals living in them. Tell the students that since there are so many types of plants and animals, they could not all live in the same area of the pond. Ask the students why. 3. Show the students the large cross-section of the pond that you made previously. Explain the different areas of the pond. The surface is the top of the water. Organisms may live on top of the surface (use a water strider as an example) or they may live right under it depending on their needs (the mosquito larva is a good example of this.) The edge of the pond is where the shallow water will be found. Tell the students to think of shallow water as water that is deep enough for them to wade. Open water is deeper and near the center of the pond where there are fewer plants growing. The bottom is the floor of the pond. It is usually muddy and covered with leaves where animals can dig down and hide from predators. Some plants have their roots buried in the bottom while other plants may float freely in the water. 4. Explain to the students that you will hand out cards that represent different plants and animals that live in the pond. Tell them you would like to them to look at the plant or animal picture so they know what it looks like. Next, ask them to read the description of where this plant or animal would be found in the pond. Explain that these areas are considered habitats because they are where the organism meets its needs for food, water, shelter, etc. 5. Show the students where you have placed the pond habitat signs. Ask them to go and sit in the habitat area that they think best suits their organism. After the groups have gathered, ask the students to read the description of their plant or animal to the rest of the group. They should decide, as a group, if the plant or animal belongs in the habitat. If it does not belong have the group work together to decide in which habitat it belongs. That student should then move to the other group. 6. Tell the students that they are going to draw their plant or animal on the pond picture in the appropriate location where it would be found. They should draw the plant or animal, write its name beside it. 7. Review the picture with the students. Have the students individually name their plant or animal, the description of where it is found, and then show the class where they drew it. If a student placed their drawing in a location that may not be correct discuss with the class where they think it should be located. 8. Discuss the fact that the descriptions of where the organisms are found may not always be accurate. Depending on the time of year, time of day, or stage of their life cycle, they may be found other places. These are basic guidelines of where the plant or animal is usually located. Decide if the student should move their organism or if it could remain where they drew it (for example, a turtle Commonwealth of Pennsylvania, Department of Conservation and Natural Resources, Bureau of State Parks 2

3 will move around the pond to all different areas it is not really specific to one part of the pond.) Evaluation: Students review the pond diagram to determine if the pond organisms were placed in their appropriate habitat. Extensions: Have the students do research to find additional information about their organism. References: Caduto, Michael, Pond and Brook, A Guide To Nature in Freshwater Environments, Council for Environmental Education and the Western Association of Fish and Wildlife Agencies, Project WILD Aquatic, Cox, Gerald, Pond Life, National Aquarium in Baltimore, Living in Water, Commonwealth of Pennsylvania, Department of Conservation and Natural Resources, Bureau of State Parks 3

4 Pond Diagram Surface Edge Shallow Surface Open Water Bottom Commonwealth of Pennsylvania, Department of Conservation and Natural Resources, Bureau of State Parks 4

5 Living In A Pond Planarian A flat worm that spends most of its time on the bottom under leaf litter and rocks. Bluegill Sunfish Will live underwater in all parts of the pond. Builds nest, that male guards, in shallow water. Leech Flattened, segmented worm found in shallow, calm, warm waters. Moves through water in graceful up and down movements. Carp Lives near pond bottom. Stirs up bottom with its snout looking for food. Will eat just about anything. Painted Turtle Can be found in all parts of the pond. Likes to sun itself on logs out of the water but will only eat its food underwater. Duckweed The smallest flowering plants in the world. They float on top of the water where their roots float freely sucking up nutrients from the water. Mayfly Nymphs (immature) live on the pond bottom. Will often be found under rocks or clinging to plant stems. Crayfish Nymph A crustacean that lives on the bottom of the pond. Will shoot itself backwards to escape predators. Broad-leaved cattail Grows in shallow water along the edge of the pond. Its roots are underwater but its leaves and flowers are above water. Can grow to be 8 ft. tall. Northern watermilfoil Grows underwater in a deeper section of the pond where little sunlight can shine through. Roots grown in the mud on the bottom or the pond. Commonwealth of Pennsylvania, Department of Conservation and Natural Resources, Bureau of State Parks 5

6 Living In A Pond Springtail Uses spring-like tail to jump along the top surface of the water. Eats plants and debris on the surface. Snail Found on rocks and plants underwater where it scrapes off algae and dead stuff to eat. Water Strider Long legged bugs that skate or jump across the top surface of the water. Whirligig Beetle Eyes are divided into two parts, one for viewing above the surface of the water, and the other below. Found floating in calmer waters. Holds bubble of air on underside when diving for food. Caddisfly Larva (immature) are worm-like and live in water. Most larva are surrounded by cases they made from rocks and plants found on the bottom where they live. Larva Clam Aquatic two shelled mollusk. Lives in the mud where it eats plankton and bacteria. Backswimmer Swims underwater to catch its food but has to come to the surface occasionally to get air to breath. Cranefly Larva (immature) is a segmented worm-like creature who has a disk on the end of its tail that it sticks above the water to get air. Larva Mosquito Larva (immature) is a worm like creature found in slow moving waters hanging on the underside surface skin of the water. (look at picture below) Scud Sideways flattened crustacean. Lives on the bottom looking for food. They are food for bottom feeding fish. Larva Commonwealth of Pennsylvania, Department of Conservation and Natural Resources, Bureau of State Parks 6