Explain to your students that one of the most serious threats to the
natural communities of plants and animals today is the introduction
of non-native plants and species by humans. When certain non-native
or exotic plant species is allowed to invade a natural native plant
population, the results can be devastating for the natives. Often natural
diseases or predators are not brought with the plants to their new homes,
thus causing a great growth in population. This can lead to a decrease
in native plant and animal diversity in a region as these uncontrolled
species increase in number. The non-native often out-competes native
in obtaining the essential requirements for growth.
This decrease in diversity affects many different food chains and may
lead to a monoculture of plants and animals where once there was a variety.
Loss of endemic or native species may mean loss of valuable genetic
material, which could someday provide valuable medicines or foods. Loss
of diversity makes our world a little less interesting and less beautiful.
The following game will introduce your students to the dilemma of the
Step 2: Before Play Begins
Designate a playing area by placing cones at edges/corners of the playing
field. (30' x 60' area works well for 20 students.)
Scatter playing chips throughout the area (each different colored chip
represents a different need for a plant or animal to survive. (White
= Shelter/Space, Red = Food/Minerals, Blue = Water)
Be sure to provide enough chips so each player may collect one chip
of each color during the first round in order to survive.
Step 3: Round One
All players will be native to the specific area. Everyone will line
up along the edges of the playing field at the start of each round.
At the sound of the whistle, players will enter the playing field, collect
one of the three different colored chips and return to the edge of the
playing field. After all of the students have returned to the sideline,
they return to the playing field and collect another chip of a different
color. Once again, they go to the sideline, returning a third time for
the third colored chip.
After a player has collected all three colored chips, he or she moves
to the sidelines to wait for the signal to end the round. All players
should survive the first round.
Step 4: Round Two
This round will be played the same as Round One, but will now include
non-native species. Two players wearing colored armbands represent a
non-native species. The non-native species are more aggressive and will
be allowed to collect two chips per trip into the playing field. The
non-native will also be allowed to return to the playing field as often
as they are able but must collect three different colors in order to
survive. The native species will be considered a survivor if he or she
collects three different colored chips as they had done in Round One.
Sound the whistle to end Round 2. Identify the survivors. Evaluate
by comparing population size and impact the non-native had on the natives.
Step 5: Round Three
Native species that did not survive Round Two become non-native for
this round. Give each new non-native an armband. Continue to play Round
Three just like Round Two.
At the end of Round Three, most, if not all, of the native population
should not survive. Evaluate as in Round Two.
After Round Three, discuss with your students what they observed as
they were playing the game. As a class, have them begin to figure out
how and why those students who played as the initial non-native species
were not only able to survive, but to actually take over the entire
Insert Africa: Episode #6: "Restless Waters," into your VCR.
Tape should already be CUED to the beginning of the tape where
there is a boat on the water and you hear, "In the dark shadow
of a new moon." Distribute the FOCUS FOR MEDIA INTERACTION
Worksheet. (See Student Materials.)
Provide your students with a FOCUS FOR MEDIA INTERACTION by
asking them to listen for and record why fishing at night gives Charles
and his crew an added advantage. What secret weapon do Charles and his
crew use to catch fish on Lake Victoria? PLAY the videotape.
PAUSE the tape after the narrator says, "And its fish
that brings Charles and his crew to these dark waters." Allow students
time to record their answers on their FOCUS FOR MEDIA INTERACTION
Worksheet, then CHECK for comprehension. Ask students to share
their answers. (Light is Charles secret weapon. Since it is dark
out, the insects are more prone to gather around the brightest source
of light, those being the lanterns. Charles and his crew float out onto
the water as the insects gather around the lanterns, and the fish begin
to gather inside the fishing nets to feed upon the abundance of insects
circling around the lights.)
As your students are recording their information, FAST FORWARD
the videotape until you see a man bent over throwing dried fish out
in front of him and you hear, "The abundance of Lake Victoria once
Provide your students with a FOCUS FOR MEDIA INTERACTION, asking
them to listen for and record three reasons that Lake Victoria's resources
are being depleted. PAUSE the videotape when you hear, "The
fish are disappearing before his eyes," and see a hawk swoop to
steal some dried fish. Allow students time to record their response,
then CHECK for comprehension. Why are the resources being depleted?
(Contamination, pollution, and over fishing have taken their toll on
FAST FORWARD the videotape to ice being thrown on a fish head
right after you see Charles with the subtitle, "That's why I am
looking for a new business one with better profits."
Provide your students with the next FOCUS FOR MEDIA INTERACTION
by asking them to listen for when the first time was that fish population
plummeted. What did the British government do to fix this problem? Was
their remedy one that helped or hindered the Lake? PLAY the tape,
and PAUSE after the narrator says, "It may be the greatest
mass extinction of its time." Allow time for students to record
their responses. If it seems that students were not able to understand
all of the information, REWIND the tape and REPLAY that
segment. After students seem to have gathered all of the information,
CHECK for comprehension. When did the fish population first plummet?
(1950.) What did the British government do to fix the problem? (The
British Government introduced the Nile Perch into Lake Victoria in order
to bolster its fish population.) Did it help or hinder the lake? (The
Nile Perch can grow to weigh over 200 pounds and measure as long as
6 Feet in length. For a period of time the tactic seemed to help the
lakes fishing industry. However, the Nile Perch has a voracious
appetite and it wiped out half of the native species of fish in the
lake. To date it is considered one of the greatest cases of mass extinction.)
Provide your students with a FOCUS FOR MEDIA INTERACTION by
asking them to listen for reasons the Nile Perch might be next on that
list. RESUME the video. PAUSE the video at the visual
CUE of a Nile Perch being filleted as the narrator says, "They
are stripping the lake of its fish." Allow students time to record
their responses, then CHECK for comprehension. Why might the
Nile perch be next? (Environmental issues, worldwide demand, and large
industrial fish boats are the main causes for the demise of the Nile
Perch in Lake Victoria.)
Break your students into small collaborative groups, and on a transparency
write the term, "Non-native Invasive Species." Ask your students
to write a definition of this term. Provide your students with about
five minutes of time to come up with an explanation. Be sure to circulate
from group to group in order to get a feel for where your students are.
Have each group write their explanation or definition of Non-native
Invasive Species on chart paper and post it on the wall for each group
to share with their classmates.
After each group has shared their explanation/definition, have the
class as a whole decide which explanation/definition they like the best,
or have them pick bits and pieces from each groups work to come
up with one working definition for the whole class.
Once the students have established a context for what they believe
is the definition for non-native/invasive species, instruct them to
go to the Web site dealing with President Clinton's Executive Order
#13112 of February 3, 1999 on Invasive Species www.invasivespecies.gov/laws/execorder.shtml#sec1.
Provide students with a FOCUS FOR MEDIA INTERACTION by asking
them to read the section of the order that deals with definitions and
record the Federal Definitions for the following terms on their FOCUS
FOR MEDIA INTERACTION Worksheet:
After students have time to record their definitions, CHECK for
comprehension. Ask students to explain the terms.
This activity is intended to help students gain an understanding of
terms and terminology that they will be reading, hearing, and saying
throughout the course of this lesson. Lead the students in a discussion
about these terms to evaluate their current knowledge base and to assess
any prior knowledge that may enhance or detract from this learning experience.
After examining President Clinton's Executive Order #13112 of February
3, 1999 on Invasive Species, students should be instructed to go to
the hyperlink for the Earth Crash Earth Spirit Web site at www.eces.org/ec/ecosystems/lakevictoria.shtml#030501.
Provide students with a FOCUS FOR MEDIA INTERACTION by asking
them to read all four articles that deal with ecological problems impacting
Lake Victoria. Have your students write a one-paragraph synopsis on
each article, focusing on the problem facing Lake Victoria, how it was
introduced, who introduced it, and what major impact it has on the Lake.
Explain to the students that if they look close enough at each article,
they will see that in each specific instance there is one major culprit
involved. If they read each article carefully, students should be able
to figure out that mankind is at the root of each of the problems facing
After students have viewed both Web sites and recorded their answers
to the FOCUS FOR MEDIA INTERACTION questions posed, lead your
class in a carefully guided discussion about what they have read and
seen so far in this lesson. Ask them if human beings could be considered
a non-native invasive species and, if so, have them cite specific examples.
After your class has discussed the possibility of mankind being considered
a non-native invasive species, explain to them that we not only can
cause these problems, but also remedy these problems before they get
out of hand.
Step 5: Round Four - Deadly Invaders Continued
Have your students return to the playing field you set up for the Introductory
Activity. Have them don the same armbands that they had on at the end
of Round Three.
This time select three players to represent various population controls
for non-native species and give them different colored armbands to distinguish
them from the rest of the group. These students will act as combatants
against the non-native species.
This time the population controls will join Round Four and begin removing
non-native plants with a ball, which they will, gently tossed and aimed
below the waist. After a non-native is hit, he or she returns the gathered
chips to the playing area and then moves to the sideline to remove the
armband. The player immediately returns to the game as a native species.
Natives are NOT tagged by the population controls. After all chips have
been collected, identify the survivors (players with a red, blue, and
white chip). Evaluate the effect population controls have on the non-native
and native populations.
Step 6: Round Five
Introduce more population controls and repeat Round Four if needed.
Upon completion of Round Four (or Round Five), discuss with your students
the following items:
What do non-native species compete with native species for?
What can non-native species do to populations of native species? How?
What can be done to control non-native species?
Would passing laws to prevent sale of non-native species that mate
cause a threat to an area if they escape be a good idea? Why or why
Discuss the advantages and disadvantages of introducing natural but
non-native predators and disease to an area to help eliminate the non-native
Discuss the effects herbicides and chemicals may have on the bio-diversity
of an area if used to eliminate non-native species.
For the Culminating Activity, there are three parts. Students will read
a news release on the Web and complete the Scavenger Hunt Worksheet
(see Student Materials) based on the information found there. Then students
will conduct a Web Quest (see Student Materials for the Web Quest Guide),
visiting several Web sites to gather and compare information. Finally,
students will create a multimedia presentation explaining the evidence
of invasive species causing environmental problems in the United States.
(A Sample Rubric for the multimedia presentation is available in Student
Materials.) A more comprehensive list of resources is available if you
would like to extend the lesson into a unit that involves more diversified
research. That list is available at http://scorescience.humboldt.k12.ca.us/fast/teachers/Invaders/resource.htm
Tell students to log onto President Clinton's News Release regarding
non-native invasive species http://darwin.eeb.uconn.edu/Documents/fws-20000207.html.
Provide students with a FOCUS FOR MEDIA INTERACTION by asking
them to compare what they learned about Lake Victoria to environmental
concerns in the United States. To help students gather needed information,
distribute the Scavenger Hunt Worksheet (see Student Materials). As
they gather the scavenger hunt information, they will begin to make
the comparison of Lake Victoria to the U.S.
After students have completed the Scavenger Hunt Worksheet, discuss
their answers until they seem to be comfortable with the language and
Step 2: "Alien Invaders" Web Quest
Explain to students that they will now conduct a guided research project
called a Web Quest. There are three sections to the research, and then
they will compile all of the information they gathered into a multimedia
project. Distribute the Web Quest Guide. The Web Quest Guide is designed
into the three sections of the research. The information students are
responsible for finding is listed, then the Web sites they should visit
follow. Students can find all of the information needed to complete
the Quest on those Web sites.
A. Research at least 4 invasive species listed at right using the Web
B. Analyze how each invasive species affects the food web in its ecosystem.
C. Describe the function each invasive species plays in its biome.
D. Explain how the number and types of organisms an ecosystem can support
is affected by each invasive species.
Who Are They? "America's Least Wanted" The Dirty Dozen
Some Non-indigenous Aquatic Species of Concern
Scientific American: Explore! Costly Interlopers
Environment News: Alien Species Cost U.S. $123 Billion a Year
Using the following Web site, compare how different invasive species
get into non-native ecosystems.
How Do They Get Here? Pathways of Invasion
Using the following Web site, propose ways people can help stop the
introduction of invasive species into non-native ecosystems.
What Can We Do to Help: Problems with Release of Exotic Fish
Show Your Stuff
Prepare a multimedia presentation (such as PowerPoint) for the Invasive
Species Council that uses convincing evidence supported by real data.
Include the following elements:
1. Clearly state your position on the issue
2. Use examples and evidence you found in your research to persuade
3. Include a bibliography of sources used
4. Anticipate and address audience concerns and counter-arguments
Make a chart or graph that lists costs per year of destruction caused
by various invasive plants and/or animals.
Design a map that locates biomes of the United States that have invasive
plants and/or animals.
FINE AND APPLIED ARTS
Draw a poster that shows ways to prevent the invasion of non-native
Draw a picture that compares two biomes and the similar ecological roles
played by the different kinds of organisms.
Make a drawing that compares predator/prey relationships.
COMPUTER APPLICATIONS AND GRAPHICS
Design a flowchart that explains the food web.
Distribute a newsletter that describes "America's Least Wanted."
Create a chart that categorizes predator/prey relationships in different
Design an ecosystem that categorizes the functions of the population
Write a research report about invasive species.
Animal profiles, photos, and news. The animal information is listed
by region of the world or by habitat. Check out the classroom activities.
Endangered species profiles, photographs, facts, state and region lists,
U.S. Fish and Wildlife Service
Choose "Creature Feature" from the menu to find information
about endangered species. Play the game "Risky Critters" about
International Wildlife Coalition
Check out their Wildlife Watch and Whale Watch portions.
World Wildlife Fund
Select a country to find information about endangered species from
that area of the world.
(United States Geological Survey)
Scroll down the page to find links to information about specific endangered
Exploring a World at Risk
From the American Museum of Natural History. Take an expedition through
the world of endangered species.
At this site you and your students will be able to explore and learn
about many different varieties of endangered marine animals.
At this site you'll find lots of fascinating facts about 246 animal
species. You'll also learn about the amazing diversity of life on earth
(both past and present), and why it's important to protect that diversity.
Endangered Animals of the World
Student-created but with a lot of useful information a collaborative
project between a school in Indiana and one in the Netherlands.
Internet Education Endangered Species Project
Student-created with information about endangered plants as well as
animals. Join School World Members in researching and reporting on Endangered
Species from around the world. Students are encouraged to refer to the
Report Guidelines when writing about their subject. The information
supplied will be written into a report and included in this list of
Five teams of high school students are working on a project to educate
consumers about the impact of wildlife trade on endangered and threatened
From the Audubon Society, this is information about endangered birds.
It identifies North American bird species that are in trouble. Watch
List Species are those faced with population decline, limited geographic
range, and/or threats such as habitat loss on their breeding and wintering
Means There's Still Time
A slide show about endangered animals.
Kids Guide to Threatened Species
How kids can make a difference to Threatened Species and Threatened
Ecological Communities. Australia is home to more than one million species,
many of which are found nowhere else in the world. About 85% of flowering
plants, 84% of mammals, more than 45% of birds, and 89% of inshore,
temperate-zone fish are endemic that is they are only found in
Australia. Changes to the landscape and native habitat as a result of
human activity have put many of these unique species at risk.
Invite a State Forest Ranger or Fish and Game Warden to your classroom
to talk to your students about their local environment in regards to
native and non-native plants and animals and how they are dealing with
Take a field trip to a local, state, or national park to explore the
area for native and non-native plants and animals.
Write a letter to the Secretary of the Department of the Interior to
ask him about what the United States is doing to combat invasive non-native
species such as the Sea Lamprey that are depleting many of the Great
Lakes of their native species of fish.
Take a fieldtrip to a local fish hatchery to experience first-hand
how native and non-native species of fish are being raised to repopulate
the local waterways or for personal consumption.
Have your students visit ethnically diverse restaurants in the region
and study the menus to see what types of non-native species are being
raised and or prepared for consumption.