How are different reef organisms dependent on one another for survival?
Teacher: Christina Bower
Subject: Science
Objective:
Students will…
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Explain and give examples of how specific relationships among producers,
consumers, and decomposers in an ecosystem affect the cycling of matter. .
Activity at a Glance
Students work in teams to conduct research about the roles that different species play
in a coral reef ecosystem. Students create a coral reef mural as a class.
Vocabulary
algae – simple plants that live in water
community – an assemblage of plants and animals living within a defined area
consumers – animals that get their energy by feeding on plants or other animals
decomposers – organisms that help to break down plant and animal matter into
nutrients that producers need to grow
ecosystem – the interacting system of living organisms and their environment
interdependence – the concept that everything in nature is connected to each other and
cannot survive without the help of other plants, animals, and abiotic factors such as sun,
soil, air, and water nutrients – any substance that promotes growth in living organisms
photosynthesis – the process of using energy from the sun to make starches and
sugars from carbon dioxide and water
phytoplankton – single-celled or multi-cellular plants
producers – organisms that use energy from the sun to produce their own food
Materials
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Ecosystems handout
coral community drawing
laptops
tape
stapler
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role of string or yarn
scissors
construction paper
colored markers
Teacher Background Information
Coral reefs are complex communities of plants and animals. The colonies of corals that
grow next to and on top of each other form the basis for this fascinating community,
providing food, shelter, and diverse living spaces for many kinds of plants and animals.
One way to understand the complex relationships among the plants and animals is to
examine the roles that different species play in the coral reef community.
Corals are unique in that they play a dual role as producers and carnivores. The
producers in the coral community also include the microscopic phytoplankton and the
larger algae that use the energy from sunlight to convert water and carbon dioxide into
sugar in the process of photosynthesis. The producers are the basis of the food chain,
providing food for the herbivores, such as the turtles and colorful parrotfish that live on
the reef. Carnivores, such as moray eels, monk seals, and sharks prey on the
herbivores, which helps to keep their populations in balance.
Darting among the corals are many beautifully colored fish that have adapted to feed on
both plants and animals. These omnivores include the moorish idol, reef triggerfish,
and the rac- coon butterfly fish. Finally, the coral community would not be complete
without the creatures that make up nature’s clean-up crew. These decomposers include
the crabs and lobsters that scavenge for food, feeding on decaying plants and animals.
Have students read the ecosystems handout and answer the comprehension questions.
Once students have completed their reading task. Provide each student with the coral
reef ecosystem diagram and discuss it as a class. Ask: what 2 main ecosystems are
illustrated.
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Ask students to describe what they know about a coral reef ecosystem.
Review what they know about the role of different members of the coral reef
community (producers, consumers and decomposers)
Ask: how might the organisms in this picture be interconnected?
Explain to students that we are going to learn about the reef ecosystem and how many
of its organisms are connected. Tell students that they will all research 2 organisms
from the picture. They will need to find out what their organism eats, where it leaves,
and whether it is a consumer, producer, or decomposer. Once they have found their
research they are to draw a picture of each organism they researched (these will be
used to create a coral reef food chain on the classroom bulletin board).
Provide each student with 1 organism from the chart below to research.
Species
Plankton
Mussels
Rock lobster
Clownfish
Sea anemone
algae
octopus
Benthic worm
goby
Hermit crab
Sea star
Jellyfish
Potato bass
Cleaner wrasse
Reef shark
Turtle
Barracuda
Surgeon fish
Cleaner shrimp
Parrot fish
Corals
What does it eat?
Where does it
live?
Producer,
consumer, or
decomposer?
Zooxanthellae
Eel
Sea cucumber
Once students have completed research have them write their information on a small
cue card. Have students add the picture of their organisms to the bulletin board.
Review:
All plants and animals need organic compounds and water in order to survive. Plants
are able to produce their own organic compounds and they are called prodcers. Animals
feed off plants and other animals, and they are called consumers. The animals that eat
plants are called primary consumers, and the ones that eat other animals, may be
called secondary or tertiary consumers. The organisms that break down the dead
material are called decomposers.
An animal may eat more than one food item and this than creates a food web within an
ecosystem. A food web is a network of feeding relationships. Each link in the food web
is important in keeping the ecosystem in balance.
Wrap up:
Students will than discuss the connections between their organisms as a class. Tell
students that while we are having a discussion they should pay close attention to which
organism eats what as we will add these connections to our bulletin board. Which
organisms were connected? Which ones were not? Which organisms are needed for a
reef community to survive? Complete the food web on the bulletin board. Ask: what do
you all notice about the food web?
Ecosystems
An ecosystem is a community of plants, animals and smaller organisms that live, feed,
reproduce and interact in the same area or environment. Some ecosystems are very
large. For example, many bird species nest in one place and feed in a completely
different area. On the other hand, some ecosystems may be physically small, such as
you would find in a meadow at the edge of a forest, or in a coral reef in the ocean.
Water ecosystems exist all over the world. We can classify them by their similar
characteristics including specific types of organisms, location, and climate. These
distinct groupings are called biomes. Water ecosystems fall into two kinds of major
aquatic biomes – freshwater and saltwater. Freshwater and marine biomes cover nearly
75 percent of the Earth’s surface. Freshwater is defined as having a low salt
concentration – usually less than 1 percent. Plants and animals in freshwater regions
are adapted to the low salt content and would not be able to survive in the ocean. These
regions include ponds, lakes, streams, and rivers.
Within ecosystems, organisms are broken down into three main roles: producer,
consumer, and decomposer. Each of these roles is extremely important in the
ecosystems of marine biomes, as each contributes to the condition and health of the
water system.
Producers are organisms that can make all of their own food in an ecosystem. In
marine biomes producers are most often plants, because they are the main source of
energy. These plants use photosynthesis to make their own food. Examples of
producers in a marine biome include zooxanthallae, kelp, seaweed and sea grass.
Make their own food? Photosynthesis?
Photosynthesis is a complex reaction. In a lot of ways, it's similar to the way your body
breaks down food into fuel that it can store. Essentially, using energy from the sun, a
plant can transform carbon dioxide and water into glucose and oxygen. In other words,
while we inhale oxygen and exhale carbon dioxide, plants inhale carbon dioxide and
exhale oxygen. Without the sun to feed plants (and the plants to release oxygen), we
might not have breathable air. Without plants to feed us and the animals most people
use for food, we'd also have nothing to eat.
Now where were we…
Now that we know what producers are let’s look at who’s eating who/what.
Consumers of an ecosystem cannot make their own food. They depend on
producers for their food and energy. Consumers cannot make their own food and
therefore eat other animals and plants. The consumers of a marine biome include krill,
mollusks, fish and zooplankton.
Decomposers are an essential component of any ecosystem. Their main role is to
recycle nutrients in dead organisms and their wastes. Most decomposers are bacteria
and fungi. Without the decomposers, there could be no life since plants would run out of
nutrients.
Comprehension Questions
Answer the questions below in your theme notebooks.
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What is an ecosystem?
What are the 2 different types of water ecosystems?
What is a producer? Provide one example.
What is a consumer? Provide one example.
What is a decomposer? Provide one example.
Describe photosynthesis in your own words.