Eat or Be Eaten

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.
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
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.
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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?
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Animal/Plant Energy Sources
Species
Eats
Eaten or destroyed by
Algae
Photosynthesis
Picklweed
Photosynthesis
Fiddler Crab
Algae, dead animals
CA Horn Snail, Fiddler
Crab
Belding’s Savannah
Sparrow
Clapper rail
Clapper Rail
Black phoebe
Crabs, snails, worms,
aquatic insects
Insects
CA Horn Snail
Algae
Mallard
Topsmelt
Aquatic vegetation and
invertebrates
Algae
Fence lizard
insects
King snakes, striped racers,
Alligator lizard, hawks,
raccoons
Mullet
Plankton, invertebrates
Insects, worms, larvae of
other fish
Mullet
Sea Lions, Osprey
Great Blue Heron, Snowy
Egret
Great horned owl (nestlings,
occasionally adults)
Humans through pollution
and habitat destruction
Bobcats, Mountain Lions,
coyotes, humans
CA Killifish
Osprey
Red Tailed Hawk
Raccoon
Coyote
Small rodents, rabbits,
snakes, lizards
Fish, crabs, rodents, birds,
bird eggs, plant material,
your garbage
Mice, rats, insects, rabbits
Coyote, raccoon, hawks
Cooper’s Hawk, Sharp
shinned hawk
Very hard shell – difficult
to eat
Raccoons, opossum,
peregrine falcon
Great Blue Heron
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
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