Eat or Be Eaten (Complements What s for Lunch? Food Chains and Food Webs Teacher Guide) Theme: Food Chains and Food Webs Objectives: Describe the living and non-living components of an environment Demonstrate that all organisms need energy and matter to live and grow Explain the role of producers, consumers, and decomposers in the environment Materials/Props Large tennis ball, vocabulary words: Producer, Consumer, and Decomposer, plants (ivy, cattail), finger puppets (owl, squirrel, hummingbird, rabbit, raccoon, mouse, insect), large food web poster board, magnifiers, magnets, drawing cards, species cards, 8x11 food chain/web page, bags of trash, extra drawing cards, owl pellets (when available), name tags. Note: Program typically takes place at Rios Avenue, allow 1.5 hours of trail time (not including intro and conclusion). General Introduction Welcome, introduce self. Define wetland and estuary. Explain wetlands are home to many different plants and animals, some are endangered. Plants and animals depend on the wetland to survive, very important to protect few remaining wetlands. Introduce Food Chain/Web program (Below is a suggested approach to introducing the topic. Modify it based on group size, student preparation and attention, etc. If the material is not all covered during the introduction, make sure to weave it into walk with the smaller groups). Today we are going to talk about how animals and plants survive here. The animals come here to rest and eat, to get their energy to survive. They get their energy from eating plants and animals. Ask the kids if they have a lot of energy, and where they got their energy from? Ask students if they had plants for breakfast. This will help them understand which foods come from plants. Tell them they are all consumers because they get their energy from eating plants and animals. Invite a child to come up and hold CONSUMER vocabulary word. Where do animals get their energy from? Start with just one animal to focus their attention to the fact that animals are consumers just like they are. Then distribute other finger puppets and plants. Try to guess what they eat and create a simple food chain, going down to plants. Then separate out animals from plants, and note that all the animals CONSUME, so they are called
CONSUMERS (point to vocabulary word). Highlight insect and note that it is a consumer and a decomposer (bring out decomposer vocab word), and ask students if they can tell you what is unique about a decomposer. Thank animal volunteers and ask plant volunteers to stay. Where to plants get their energy from? The Sun! (ask a student to hold the sun). The sun is the most important object in our universe. Without it plants and animals would not be able to survive. Almost all life on earth depends on the sun for its energy. Because plants make or produce their own food, there is a special word we use to describe plants, and it starts with a P, can anyone tell me what that word is? PRODUCERS. Plants are producers because they use energy from sunlight to produce their own food, they are not CONSUMERS. To help you remember that plants are Producers, think of 2 P s, P for Plant and P for Producer. Ask a student to hold the PRODUCER card. Review vocabulary words Consumers, Decomposers, and Producers. Walk Preparation Prepare students for a walk, divide into smaller groups go over trail rules. General discussion points while hiking All organisms need energy to survive. The ultimate source of energy is the sun. All life depends upon living (biotic) and non-living (abiotic) things. Living organisms depend on one another and on their environment for survival. In an ecosystem, energy flows from the sun to producers (plants), to consumers (animals), and ending with decomposers. Plants are primary producers because they produce their own food. Consumers must depend on plants or other consumers to get the energy they need. A food chain shows transfer of food from one living thing to another. Breaks in a food chain affect life in both directions from the break. A food web is many interconnected food chains. At each link in the food chain, some of the food energy is used, therefore less energy is available for consumers who are further from the producers in the food chain (this may be a hard concept to grasp, read the group before introducing). Everything in nature is recycled and reused. Specific examples to discuss along the trail As you come across different animals (insects, lizards, birds) discuss what they might eat, and what might eat them. If appropriate, introduce vocabulary words herbivores, carnivores, and omnivores. You are likely to see lizards, what is their role in ecosystem? Food for birds, bats, raccoons, and snakes. discuss what would happen if all the lizards were wiped out, how would that affect the food chain? What role do insects play? Food source for many birds, bats, and spiders. Many plants rely on insects for pollination. Make sure students know the term, pollination. 2
. What happens to animals that die in nature? Are they buried, put into the trash? No, nature is able to recycle them. Crows, ravens, insects, flies, fungi, bacteria. They all have a role in helping to break down the animal and return it back to the soil as nutrients. These nutrients enrich the soil and allow more plants to grow. Compare pickleweed, riparian, and sagebrush plant communities. Why are they so different? Because the non-living components found in these habitats are different. How? Salt water, freshwater, water-logged soil vs. dry soil. These non-living components determine what plant communities can survive there, which determines the types of plants, insects, reptiles, and mammals that will be able to survive there. Activities to incorporate in the Field 1) Exploring Soils. Use magnets to observe soil and see if you can pull out magnetite (iron). By doing this, you will see that soils are a mix of many things, both organic and inorganic. Ways to introduce this topic might be: just like us, plants need many nutrients to grow and survive. For example, iron is an important nutrient in humans, and plants need it as well. They are able to pull it out of the soil, and when we eat plants or other animals, we get the iron we need to survive. Let s see if we can find some iron in this soil. Very simplified version: soils are made up of many different materials that plants use to grow let s see what we can find. 2) Food web laminated page Sit for a moment to review the difference between a food chain and food web, using the laminated page from Teacher Guide. Try to explain the energy flow, and who is getting energy from where, and how a break in the food chain can affect the entire ecosystem. An ecosystem is made up of all the living and nonliving things that interact in an area. Students can point to living and non-living things in diagram. Might be a good time to introduce words omnivore, carnivore, herbivore, and decomposers. 3) Exploring soil, plants, and insects: Use magnifying lenses to get a closer look at the soil, see salt crystals on saltgrass, observe insects. Do not let the kids hold on to the magnifying glasses for an extended period of time. Take them out for the activity, then collect them and put them away. 3
4) Decomposers and recycling - Discuss how things in nature are recycled naturally, compared to how some man-made things, such as plastic do not break down naturally. It is important that we recycle plastic, but it is even more important that we try to limit the amount of plastic we use because plastic NEVER breaks down. Why is that bad? Animals mistake plastic for food, causing them to choke, or mistakenly think they are full. A straw might look like a worm, a plastic bag like a jelly fish, a bottle cap like a shellfish. FBI - Fungus, Bacteria, and Insects Nature s decomposers. Optional Activities 5) Species Cards Allow students to pick card, guess what that animal might eat or who eats it. These will also allow for discussion of food chains and webs, as well as a means to reinforce vocabulary words herbivore, carnivore, and omnivore. Can be paired with following sketching activity. 6) Sketching Find a quiet place to sit. Ask students to sketch a P, C, or D on an index card. For Habitat we are looking for wetland, riparian, sage scrub, or a combination. If students seem interested, have some of them share what they drew and how it is labeled. Do not spend more than 10 minutes on this activity. When done collect cards and pencils. We will want to give all the cards to the teachers so they can recreate a food web in the classroom. 7) Owl Pellets Carry your own in a bug box, or coordinate with other docents to plant one along the trail in advance. Wrap Up Living organisms all have the same basic needs and depend on non-living things for survival (energy, nutrients, air, shelter, and water). Moving, growing, and eating all require a source of energy. Where do plants get their energy from? Where do animals get their energy from? Did anyone see a producer, or a consumer? Let kids share what they saw and for the producers, ask if they know what it eats and if it is a omnivore, carnivore, or herbivore? Why are decomposers (FBI) important? Did anyone see anything that didn t belong in nature? 4
Animal/Plant Energy Sources Species Eats Eaten or destroyed by Algae Photosynthesis CA Horn Snail, Fiddler Crab Picklweed Photosynthesis Belding s Savannah Sparrow Fiddler Crab Algae, dead animals Clapper rail Clapper Rail Crabs, snails, worms, Coyote, raccoon, hawks aquatic insects Black phoebe Insects Cooper s Hawk, Sharp shinned hawk CA Horn Snail Algae Very hard shell difficult to eat Mallard Aquatic vegetation and invertebrates Raccoons, opossum, peregrine falcon Topsmelt Algae Great Blue Heron Fence lizard insects King snakes, striped racers, Alligator lizard, hawks, raccoons Mullet Plankton, invertebrates Sea Lions, Osprey CA Killifish Insects, worms, larvae of other fish Great Blue Heron, Snowy Egret Osprey Mullet Great horned owl (nestlings, occasionally adults) Red Tailed Hawk Small rodents, rabbits, snakes, lizards Humans through pollution and habitat destruction Raccoon Fish, crabs, rodents, birds, bird eggs, plant material, Bobcats, Mountain Lions, coyotes, humans your garbage Coyote Mice, rats, insects, rabbits Humans, cars (Note: For Content Standards for CA Public Schools, Vocabulary list, and food web diagram see coinciding Teacher Guide: What s for Lunch? Food Chains and Food Webs) Developed for SELC Docent Training 2009, revised 2012 5