Ecosystems5th Grade

Unit Duration: 2 weeks

Integrated Curricular Areas: Language Arts (advocacy letters, journaling, observations), Science, Social Studies (relating ecosystems to the endangerment of animals in our world), Art (drawing pictures of assigned animal, drawing observations of ecosystems in a bottle), Physical Education (Migration hop-scotch game)

Rationale: Students live in a world where change is occurring on an everyday basis. The world in which they live experiences continual environmental threats, most commonly introduced by humans. Students must understand the effects of these human changes on the environment.

Overview:1. Lesson 1: What is an ecosystem?2. Lesson 2: Effects of Endangerment on Ecosystems3. Lesson 3: Ecosystem in a bottle4. Lesson 4: Wetlands Migration Hopscotch

Goals and Objectives:- Students will understand the importance of ecosystems in the world in which they

live.-

Planning steps:- Key questions

o What is an ecosystem?o Why are ecosystems important in the world?o Why should students know about ecosystems?o What are examples of ecosystems in La Crosse?o How do we maintain ecosystems in our area?o What animals/species are important in an ecosystem?o What are different examples of ecosystems; are they only on land?o How do we, as teachers, make ecosystems fun for students?

- Planning the lessonso As a group, we collectively decided to brainstorm types of lessons, search

the internet for examples of those lessons, and split up the lessons according to interests.

o We decided to have the lessons written by the first week of October in order for us to get together and organize the rest of the unit.

o We used the same lesson plan format to create a consistent format for the lessons.

o We decided on the order of our lessons; which lesson would be a good introduction? Which lesson would be a good conclusion? What should the order of the middle lessons be?

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Supplemental Components: - Parent Letter (please see Supplemental Components section on page 17)- Biosphere worksheet (to be used in lesson 1; page 15)- Monitoring an ecosystem worksheet (to be used in lesson 3; page 16)- Bulletin Board plan (page 18)- Tests (page 18)

o Online cumulative test o What is an ecosystem reading

- Field tripo Myrick Parko Riverside Parko Bluff hikeo USGS o Goose Island

Understanding of Learning/Assessment- Pre-assessment

o Students complete a pre-knowledge worksheet on the biosphere. - Lesson 1

o In their science journals, students will be asked to write about their observations during the station activity.

They will need to describe why they thought each station was either an ecosystem or not an ecosystem and the biotic and a-biotic factors they found in each station.

They will also need to list the reasons why the moldy sandwich and nail polish bottle are not ecosystems and what they could add in order to make them ecosystems.

- Lesson 2o Once the students are all returned to their seats, have them each go to a

computer. Direct them to the website: www.bagheera.com . Select the ‘Endangered’ tab and have students chose an animal of their choice. They should read about the animal that interests them, and take some notes. Tell students they need to answer the following questions on a sheet of paper:

What type of ecosystem does this animal live in? What part of the world?

Why is this animal endangered? How might its extinction affect other parts of the ecosystem? What can we do to help save the animal?

o Have students create a poster for their animal that includes the answers to their questions, as well as an artistic representation of their animal.

o As students are researching the answers to their questions, go around to each student to make sure they are finding the information they need.

o Once all students have created their posters, have them share with each other in small groups.

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o Display posters in classroom/ hallway.- Lesson 3

o In their science journals, students will write about their daily observations throughout the four week period.

The students note the changes they observe on a daily basis. The students predict what they think might happen when the

grasshoppers and pill bugs are introduced after the first week. The students predict what they think might happen when the fish

are introduced after week 2.5. The students predict what will happen when pollutants are

introduced into the ecosystem. o At the end of the four week observation period, students will write a short

paper about the importance of ecosystems in our world today. o Students will take their observations from the polluted ecosystems and

write a letter to local, state, or national policymakers stating the importance of preserving our nations’ ecosystems.

- Lesson 4o To evaluate students, call them to a plan of action. They can choose

between holding a debate (for those who prefer to speak in public), writing a persuasive letter to a congressman or other official who has decision-making power with the conservation of wetland ecosystems, or creating some type of public service announcement (posters, commercial, etc.). In order for students to do these types of final projects, they must have a firm understanding of what an ecosystem is, the interconnectedness of the animals and plants in ecosystems, the threats that ecosystems are experiencing, and the importance of ecosystems. Evaluate students based upon their demonstration of this understanding and the quality of their plan of action which should be of high enough quality to be presented to the public.

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Lesson 1: What is an Ecosystem?

Teachers: Kim Frazier, Jennifer Friedman, Nora Tetkoski, Anna Zimborski Date: 10/4/09Title of Lesson: What is an Ecosystem?Subject/Topic: Science/EcosystemsGrade: 5th grade Duration: 2 hours (over two class periods)**Note: lesson adapted from www.eduref.org lesson plan # AELP-ECL0200

I. RationaleStudents explore different types of ecosystems to develop a general idea of the ecosystem and being to understand different types of ecosystems in the environment and the world.

II. State Standards Met:o Science

o F.8.2 Show how organisms have adapted structures to match their functions, providing means of encouraging individual and group survival within specific environments

o F.8.7 Understand that an organism's behavior evolves through adaptation to its environment

o F.8.8 Show through investigations how organisms both depend on and contribute to the balance or imbalance of populations and/or ecosystems, which in turn contribute to the total system of life on the planet

o Language Artso B.8.1 Create or produce writing to communicate with different audiences

for a variety of purposes.o Art

o C.8.9 Come up with ideas and carry them through to completion of an original work of art

III. Objectives:o Students will be able to define the term ecosystem, biotic factor, and a-biotic

factor.o Students will be able to explain what an ecosystem is and the roles that humans

play in ecosystems. o Students will be able to discuss ecosystems in their surroundings.

IV. Materials: o Aquarium

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o Plant with wormo Bottle of nail polisho Moldy Sandwich o Worksheet

V. Procedures: o The teacher will describe an ecosystem to their class. They will let students know

that an ecosystem is part of the biosphere on the Earth and that the biosphere is the part of the Earth that contains all living things and systems of organisms that interact with each other. The teacher will inform students that the organisms that make up the living part of an ecosystem are called biotic factors and that organisms depend on other biotic factors for food, shelter, protection, and reproduction. The teacher will also inform students that nonliving things that we find in an ecosystem are called a-biotic factors and a-biotic factors have an effect on the number of organisms living in an ecosystem. Some examples of a-biotic factors include soil, water, temperature, and sunlight.

o Students complete the biosphere worksheet in class and discuss the findings. o Students will then observe a working aquarium. Students will get into groups of

two and discuss types of biotic and a-biotic factors that they observe in the aquarium. They will also discuss the various elements that may be found in an ecosystem. The students will then discuss whether these elements are biotic or a-biotic.

o The teacher will set up four stations: an aquarium, a plant with a worm, a bottle of nail polish, and a moldy sandwich. The teacher will then divide the class into groups and they will rotate between the stations to observe. As groups, the students will decide whether the stations are ecosystems or not. Also, the student groups will be asked to determine whether certain factors in the stations are biotic or a-biotic. The information will be recorded by one student per group.

o Next, one different student per group will share their results with the class and discuss the different biotic and a-biotic factors found in the different stations. They should have determined that the aquarium and plant with a worm are both ecosystems but the moldy sandwich is just part of an ecosystem and the nail polish is not an ecosystem at all. Next, students will be asked to share their ideas about what would make the moldy sandwich and nail polish an ecosystem.

VI. Check for Understanding: o In their science journals, students will be asked to write about their observations

during the station activity. o They will need to describe why they thought each station was either an

ecosystem or not an ecosystem and the biotic and a-biotic factors they found in each station.

o They will also need to list the reasons why the moldy sandwich and nail polish bottle are not ecosystems and what they could add in order to make them ecosystems.

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o Although the above was mostly a summary of the station activity for the students to write down and reflect upon, students will also be asked to describe what an ecosystem is to them and how it affects them in their own lives.

Lesson 2: The Effects of Endangerment on Ecosystems

Teachers: Kim Frazier, Jennifer Friedman, Nora Tetkoski, Anna Zimborski Date: 10/09/09Title of Lesson: The Effects of Endangerment on EcosystemsSubject/Topic: Science/EcosystemsGrade: 5th grade Duration: 3 hours (3 class periods + time to research)** Note: This is an adaptation of a lesson titled “Elementary Ecosystems” put out by National Geographic and can be found at www.nationalgeographic.com/expeditions/lessons .

VII. RationaleStudents understand that small changes in an ecosystem can devastate the entirety of an ecosystem.

VIII. State Standards Met:o Science

o A.8.6 Use models and explanations to predict actions and events in the natural world

o A.8.8 Use the themes of evolution, equilibrium, and energy to predict future events or changes in the natural world

o F.8.8 Show through investigations how organisms both depend on and contribute to the balance or imbalance of population and/or ecosystems, which in turn contribute to the total system of life on the planet

o F.8.10 Project how current trends in human resource use and population growth will influence the natural environment, and show how current policies affect those trends

o Language Artso B.8.1 Create or produce writing to communicate with different audiences

for a variety of purposes.o B.8.2 Plan, revise, edit, and publish clear and effective writing.

o Social Studieso A.8.11 Give examples of the causes and consequences of current global

issues, such as the expansion of global markets, the urbanization of the developing world, the consumption of natural resources, and the extinction of species, and suggest possible responses by various individuals, groups, and nations

IX. Objectives:

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o Students will be able to perform a simulation to demonstrate the interdependencies within an ecosystem

o Students will be able to predict the possible effects of the extinction of a single species

o Students will be able to research an endangered animal of choice, explain why it is endangered, and what can be done to help save the animal

X. Materials: o Computers with internet access (one per student preferred)o Drawing materials (paper, colors)o Cards to assign organisms: marsh grass, crab, heron, rat, great horned owl,

worm, fish, human, leaf hopper, tree frog. Make enough so that each student gets one. If it is lower on the food chain, make more so that the populations are fairly representative. For example, a class of 25, you might make 5 for marsh grass, 2-3 of the others in between, one human, one owl, and one heron.

XI. Procedures: o Begin by asking students questions about ecosystems that they have already

learned (what an ecosystem is, the relationships between animals, what a food chain is, etc.). Relate that to the local ecosystem of the marsh. Tell students that you are going to do a simulation of the marsh food chain.

o Give each student a card and have them sit in groups in an open area in the classroom. Introduce each group to the rest of the class (“over here, we have two rats… and Johnny is the one and only heron”) so that students are familiar with the animals in the marsh ecosystem. At the board, have students assist you in constructing a diagram of the food web.

o Tell the students that a disease has been introduced to the leaf hoppers and killed of the entire population of them. Have the students who are leaf hoppers go back to their seats. Ask the students if this would impact any other animals. They should say that the tree frogs do not have anything to eat, so they die. Have the tree frogs sit at their seats, too. Explain that what happens to one species impacts another species in an ecosystem. Have students predict what might happen to the marsh grass (there would be more since the leaf hoppers won’t be eating it). How will this affect the other animals’ populations? (Their populations may increase). Explain to students how the interdependence of the animals means there needs to be a balance in the populations, which we call an equilibrium.

o Have the leaf hoppers and tree frogs come back from their seats and join the group again. Now say that there was a fire in the marsh. The trees have been destroyed, leaving no homes for the owls. The marsh grass has also been burned. What happens to all of the animals? Send the marsh grass back to their seats. Also, send the owls back to their seats. Explain that the owls may have either died or migrated to another area. Go through the groups dependent of the marsh grass for food, and dismiss them back to their seats. Do this for the other groups as well, since they depend on the animals who are dependent on the grass. What might the human do? (Find food sources elsewhere).

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XII. Check for Understanding:

o Once the students are all returned to their seats, have them each go to a computer. Direct them to the website: www.bagheera.com . Select the ‘Endangered’ tab and have students chose an animal of their choice. They should read about the animal that interests them, and take some notes. Tell students they need to answer the following questions on a sheet of paper:

o What type of ecosystem does this animal live in? What part of the world?o Why is this animal endangered?o How might its extinction affect other parts of the ecosystem?o What can we do to help save the animal?

o Have students create a poster for their animal that includes the answers to their questions, as well as an artistic representation of their animal.

o As students are researching the answers to their questions, go around to each student to make sure they are finding the information they need.

o Once all students have created their posters, have them share with each other in small groups.

o Display posters in classroom/ hallway.

Example Food Web:

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Marsh Grass

Leaf Hopper

Tree Frog

Human

Great Horned Owl

Earth Worm

Marsh Rat

Heron

Crab

Fish

Lesson 3: Ecosystem in a Bottle

Teachers: Kim Frazier, Jennifer Friedman, Nora Tetkoski, Anna Zimborski Date: 10/6/09Title of Lesson: Ecosystem in a bottle: Understanding relationshipsSubject/Topic: Science/EcosystemsGrade: 5th grade Duration: 3 hours setup (three class periods), plus 4 weeks of daily observations**Note: This lesson has been adapted from www.eduref.org lesson plan # AELP-ECL0014

XIII. RationaleStudents observe first hand the interactions between species in an ecosystem and also note the effects of pollution on the same ecosystem.

XIV. State Standards Met:o Science

o A.8.6 Use models and explanations to predict actions and events in the natural world

o B.8.3 Explain how the general rules of science apply to the development and use of evidence in science investigations, model-making, and applications

o C.8.6 State what they have learned from investigations, relating their inferences to scientific knowledge and to data they have collected

o F.8.2 Show how organisms have adapted structures to match their functions, providing means of encouraging individual and group survival within specific environments

o F.8.8 Show through investigations how organisms both depend on and contribute to the balance or imbalance of populations and/or ecosystems, which in turn contribute to the total system of life on the planet

o Language Artso B.8.1 Create or produce writing to communicate with different audiences for a

variety of purposes.o F.8.1 Conduct research and inquiry on self-selected or assigned topics, issues, or

problems and use an appropriate form to communicate their findings. o

XV. Objectives:o Students will investigate the relationships among organisms in a closed

ecosystem.

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o Students will be able to describe the role each biotic and abiotic variable plays within an ecosystem.

o Students will be able to observe, record, and interpret how different components of an ecosystem change as they interact with one another and their environment.

XVI. Materials: o 2-liter bottle ecosystem set-upo 3 plastic cups Part Ao Soilo Fiberglass screeno Rubber bando Spoon Part Bo Watero Droppero Seeds: grass, alfalfa, mustard Part Co Toothpickso Hand lenso Permanent markero Leaves, grass, and sticks from outsideo Grasshopperso Pill bugso Fish

XVII. Procedures: Part 1:o The teacher distributes the pre cut 2-liter bottles for the ecosystem. The students

remove part A from part B and C. o The screen is rubberbanded at the spout of part A. o One cup of soil is added to the bottle. The area is divided into four parts. The

three different types of seeds need to be planted in each quarter. The last quarter should be filled with leaves, grass, and sticks from outside.

Grass Mustard

Alfalfa Outdoor materials

o Water the newly planted seeds.o Allow seeds to germinate for one week. Make daily observations.Part 2:o Introduce critters to the ecosystem.o Complete attached worksheet to make predictions about how the grasshoppers

and pill bugs will affect the ecosystem.o Continue daily observations.o Prepare parts B and C for the introduction of fish.

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o Put one cup of gravel/sand at the bottom of part C.o Add two cups of water to part C.o Add one teaspoon of chlorine remover to the water. o Let sit for two days.Part 3:o Introduce water plants, algae, and fish to the ecosystem. o Continue observations.Extension:o Teacher adds pollutants to his/her ecosystem.o Students also observe the polluted ecosystem.o Students take detailed notes about the affect of pollutants on the ecosystem. o Share observations and discuss how students can write to policymakers in the

community to help prevent pollution in the environment. Students explain how the pollutants affect the vegetation, land animals, and water animals.

XVIII. Check for Understanding: o In their science journals, students will write about their daily observations

throughout the four week period. o The students note the changes they observe on a daily basis.o The students predict what they think might happen when the

grasshoppers and pill bugs are introduced after the first week.o The students predict what they think might happen when the fish are

introduced after week 2.5.o The students predict what will happen when pollutants are introduced into

the ecosystem. o At the end of the four week observation period, students will write a short paper

about the importance of ecosystems in our world today. o Students will take their observations from the polluted ecosystems and write a

letter to local, state, or national policymakers stating the importance of preserving our nations’ ecosystems.

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Introducing the Critters

i. When we add grasshoppers, how will they affect the ecosystem?

ii. What is the role of the pill bugs in the ecosystem?

iii. How do these two creatures work together in the ecosystem?

iv. Which creature is a decomposer and which create creates waste to be decomposed by the other?

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Lesson 4: Wetlands Migration Hopscotch

Teachers: Kim Frazier, Jennifer Friedman, Nora Tetkoski, Anna Zimborski Date: 10/9/09Title of Lesson: Wetlands Migration HopscotchSubject/Topic: Science/EcosystemsGrade: 5th grade Duration: 1 hour (1 class period)**Note: This lesson was adapted from www.lessonplansearch.com/Thematic_units/ecosystems/index.html

I. RationaleStudents realize the importance of ecosystems and advocate for the protection of ecosystems.

II. State Standards Met:○ Science

o F.8.8 Show through investigations how organisms both depend on and contribute to the balance or imbalance of populations and/or ecosystems, which in turn contribute to the total system of life on the planet

o F.8.9 Explain how some of the changes on the earth are contributing to changes in the balance of life and affecting the survival or population growth of certain species

o F.8.10 Project how current trends in human resource use and population growth will influence the natural environment, and show how current policies affect those trends.

○ Language Artso F.8.1 Conduct research and inquiry on self-selected or assigned

topics, issues, or problems and use an appropriate form to communicate their findings.

o A.8.4 Read to acquire information.o Physical Education

o B.8.4 Explain how people can enjoy an activity if they are not gifted athletes

III. Objectives Students will learn the importance and interconnectedness of ecosystems,

especially wetlands.

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Students will put together a plan of action to help protect the wetland ecosystems.

IV. Materials Chalk (if able to go outside) or masking/colored tape (if inside) Enough space to make a hopscotch about 10 feet long and 4 feet wide

V. Procedures

Remind and review with the students that they have been learning about ecosystems during this unit. Ask what an ecosystem is, what it is used for, how an ecosystem works, etc. Then explain to the students that they are now going to learn about the importance of ecosystems.

Have students line up at the beginning of the hopscotch design. The students are representing migrating birds that use wetland ecosystems as a place to stop to rest and feed along their migration. Each one of the students should hop through, hitting all ten spaces. After the last student goes through, cross off one of the boxes. Explain to the students that crossing off a box is like a wetland being destroyed along the migration path of the birds because of construction, pollution, etc. Next, the students should hop through the hopscotch again without landing on the box that was crossed out. After each student has made it through, cross off another box. Continue having students hop through the hopscotch after each time that another box is crossed out.

Eventually the students will not be able to make it across because too many boxes have been crossed out. At that point, explain that when too many wetlands have been destroyed, birds can no longer migrate and therefore, many simply die out since they cannot complete their journey. Begin a discussion here about the current destruction of the wetlands and the effects of this destruction. Many other plants and animals are affected by the loss of the wetland ecosystem.

VI. Check for Understanding

To evaluate students, call them to a plan of action. They can choose between holding a debate (for those who prefer to speak in public), writing a persuasive letter to a congressman or other official who has decision-making power with the conservation of wetland ecosystems, or creating some type of public service announcement (posters, commercial, etc.). In order for students to do these types of final projects, they must have a firm understanding of what an ecosystem is, the interconnectedness of the animals and plants in ecosystems, the threats that ecosystems are experiencing, and the importance of ecosystems. Evaluate students based upon their demonstration of this understanding and the

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quality of their plan of action which should be of high enough quality to be presented to the public.

THE ECOSYSTEMThe ecosystem refers to

____________________________________________________

Ecologists have divided the ecosystem into different organizational levels. These

include:

____________-One individualliving thing.

_________-A group of organisms so similar to one another that they canbreed and produce fertile offspring.

___________-Groups of individualsthat belong to the same species and

live in the same area

__________-Different populationsthat live together in a defined area.

__________-A collection of all theorganisms that live in a particular

place together with their nonliving or

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physical environment.

__________-A group of ecosystemsthat have the same climate and

dominant communities.

Monitoring an ecosystemIn order to monitor an enclosed ecosystem, various components need to be observed.

1. Distinguish between biotic and abiotic factors

a. Biotic factors refer to ______________________________________________

Name three biotic factors necessary for the terrestrial chamber.

_____________________ ________________________ ____________________

Name three biotic factors necessary for the decomposition chamber.

_____________________ ________________________ ____________________

Name three biotic factors necessary for the aquatic chamber.

_____________________ ________________________ ____________________

b. Abiotic factors refer to ______________________________________________

Name five or more abiotic factors necessary for the terrestrial chamber.

____________________ _______________________ _________________________

__________________ _______________________ __________________________

Name five or more abiotic factors necessary for the decomposition chamber.

____________________ _______________________ _________________________

__________________ _______________________ _________________________

Name five or more abiotic factors necessary for the aquatic chamber.

____________________ _______________________ _________________________

__________________ _______________________ __________________________

c. An enclosed ecosystem is considered stable or self- sustaining if materials are

cycled and

there is a flow of energy. List 4 material cycles necessary for ecosystem stability.

____________________________________ _________________________________

____________________________________ _________________________________

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Dear Parent/Guardian,

Your child is about to embark upon a very special and exciting journey!

In the weeks ahead, the focus of study for our class will be ecosystems: what they are and how they impact our Earth. The students will investigate what is an ecosystem, how ecosystems are endangered, build their own ecosystems, and study the destruction of ecosystems on a particular species.

We will be keeping journals throughout the unit. Our classroom activities include creating our own food chair, exploring what is and what is not an ecosystem, building our own ecosystems, journaling about our experiences, and writing to local politicians and environmentalists. During the course of the program, the students will have the chance to act as scientists and explore the word in which they live.

We ask that you help our class by being a part of your student's educational experience. Please take some time to discuss our lessons with your child. You can enhance your child's learning by visiting the library to find out more about the ecosystems in our area. Also, with your child, watch for information about the local ecosystem in the news and discover ways in which their immediate ecosystem is threatened. You may be surprised by how much is out there!

We hope you will remain informed of what is going on in the classroom and remain as excited about this exploration as we are!

Thank you! I hope we can all work together to make this unit insightful and exciting!

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Bulletin Board1. Focus on La Crosse ecosystems.2. Provide space for class observations of the ecosystems in a bottle.3. Ideas for research papers4. Addresses for congress people.

Tests1. http://www.quia.com/quiz/277724.html?AP_rand=229283375

a. This website contains a cumulative test for habitats and ecosystems from Quia

2. What is an Ecosystem reading and questionsWhat Is an Ecosystem? by Susan Quinlan

Plants help animals by making food from sunlight, air, water, and soil minerals. Different animals help plants by carrying their pollen or seeds, or by enriching the soil with their droppings. All the plants, animals, and other living things in one place interact with one another in many ways. They fit together like the pieces of a three-dimensional puzzle. Scientists call this puzzle an ecosystem. An ecosystem includes a place, all the living things in it, and all the connections among them.

Because there are so many connections in an ecosystem, it can be hard to figure out exactly how it works. Scientists were puzzled, for example, by the underwater ecosystems around two Aleutian islands that lie near each other. Amchitka and Shemya Islands are surrounded by rocky ocean floor and clear water of the same temperature and saltiness. Since the places are nearly identical, one would expect to find similar life there. Instead, the two islands have very different ecosystems.

The ecosystem around Amchitka Island has dense underwater forests of giant kelp (a plant-like organism that lives in the ocean). It has a large population of shrimp-like animals and fish, thousands of sea otters, bald eagles, and lots of seals. In contrast, Shemya Island has no sea otters, few seals, and no bald eagles. Underwater, there is almost no giant kelp, few shrimp-like animals, and few fish. Instead, the rocky ocean floor is carpeted with bottom-dwelling, hard-shelled animals, such as sea urchins, barnacles, and blue mussels.

Why are the ecosystems around these islands so different? The scientists discovered that all the differences arose because Shemya lacked a single animal species—the sea otter. Sea otters disappeared from the islands in the late 1800s when hunters killed them for their thick, soft fur. Fortunately, a few sea otters survived. After decades of protection, they finally returned to Amchitka. But they had not yet reached Shemya when the scientists were there.

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The scientists discovered that the sea otters triggered a series of ecosystem changes. These diving mammals eat many different underwater animals, including sea urchins. Any large urchins that venture into nearshore waters where the sea otters dive are quickly eaten.

On Shemya, however, where there are no sea otters, the ocean floor is patrolled by hordes of sea urchins. Sea urchins eat giant kelp. They also gnaw through the anchoring base of the kelp. Without an anchor to the ocean bottom, the kelp soon washes ashore and dies. So giant kelp can’t survive in places like Shemya.

On Amchitka, where sea otters limit sea urchin numbers, a giant kelp forest thrives. A kelp forest slows ocean currents and makes waves smaller, creating pockets of calm water. Shrimp-like animals flourish in this quiet water and feast on dead kelp. In contrast, bottom-dwelling animals, like barnacles and mussels, are smothered by sand and silt that settles to the bottom in calm water. Many kinds of fish feed on shrimp-like animals, so there are more fish in kelp forests. Since harbor seals and eagles eat fish, more of them live around kelp forests, too.

An ecosystem isn’t just a collection of plants and animals in a particular place—it’s a system of connections. The invisible connections that link the living and nonliving parts are what keep the ecosystem working. Just as the absence of sea otters dramatically changed the underwater world around Shemya Island, seemingly small changes in any ecosystem can make many surprising things happen.

Because nature’s connections are so complicated and because we know so little about them, scientists often can’t predict what will happen when humans change nature. Often we discover nature’s connections only after we break them—or later, when we try to put nature back together through ecosystem restoration.

1. Which sentence tells the main idea of this article? A. Sea urchins are important to a healthy island ecosystem. B. Hunters in the 1800s changed the island ecosystems forever. C. Sea otters, seals, and sea urchins live in the same ecosystem. D. Changes in nature can produce unexpected results in an ecosystem.

2. With which statement would the author of “What Is an Ecosystem?” most likely agree?

F. People should avoid activities that may harm an ecosystem. G. Ecosystems need change in order to stay strong and healthy. H. Ecosystems can never be repaired once they have been damaged. I. Scientists should be able to predict the effects of changes on ecosystems.

3. Which two words from the article have OPPOSITE meanings? A. gnaw, feast B. series, single C. washes, settles D. system, collection

4. By reading the article and looking at the map, you can tell that Shemya and Amchitka Islands are located

F. along the coast of Russia. G. along the coast of Canada. H. between the Arctic Ocean and the Bering Sea.

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I. between the Pacific Ocean and the Bering Sea. 5. How are the islands Amchitka and Shemya alike?

A. Similar water surrounds both islands. B. Sea otters have returned to both islands. C. Kelp beds have grown around both islands. D. Similar fish populations live around both islands.

6. What caused the sea life around Amchitka Island and Shemya Island to be so different?

F. Bald eagles preferred to nest on Shemya Island. G. The sea otters returned to only Amchitka Island. H. Shrimp-like animals grew larger around Shemya Island. I. The water temperature was warmer around Amchitka Island.

7. According to the article, which event happened first? A. Otters were protected on Amchitka. B. Sea urchins ate the giant kelp forests. C. Sea urchin numbers grew around Shemya. D. Otters nearly disappeared from the islands.

8. Which detail from the article helps show how a sea otter’s diet can protect kelp forests?

F. Seals live in the kelp forests. G. Sea urchins eat and destroy kelp. H. Shrimp-like animals eat dead kelp. I. Fish make their homes in kelp forests.

9. Read this sentence from the article. On Amchitka, where sea otters limit sea urchin numbers, a giant kelp forest thrives. This sentence means the sea otters

A. compete with sea urchins for food. B. keep track of sea urchins in the kelp. C. keep the sea urchin population down. D. find sea urchins that live in kelp forests.

10. Read these sentences from the article. A kelp forest slows ocean currents and makes waves smaller, creating pockets of calm water. Shrimp-like animals flourish in this quiet water and feast on dead kelp. What does the word flourish mean?

F. grow well G. seek warmth H. become quiet I. avoid enemies

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