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EXTINCTION STINKS!
MASTER TEACHER Veronica Zonick
GRADES 9-10
OVERVIEW
This multi-day unit on endangered species uses world wide web
resources to give students an up-to-date perspective on the causes of the
decline and reemergence of Bald Eagle populations in the United States.
It also presents students with recent evidence on how DDT prevented successful
reproduction, and data on how DDT increased, or biomagnified, in the food chain.
This lesson also provides students with real-life applications for ratios
and slope.
ITV SERIES
Interactions-- Real Math, Real Careers: Endangered Species
LEARNING OBJECTIVES
Students will be able to:
*Define endangered species
*List the factors which previously threatened the existence of
the Bald Eagle
*Describe factors that continue to affect the survival of Bald
Eagles.
*Calculate productivity for populations of bald eagles
MATERIALS
Computers with internet access (preferably one per 2-3
students.)
Bookmark the following internet addresses on each computer:
(If internet access is unavailable at school, information from
the needed web pages can be downloaded and printed for classroom use.)
Bald Eagle, Haliaeetus leucocephalus, USFWS
http://www.fws.gov/r9endspp/i/b/sab0h.html
Bald Eagle Species Account
http://www.fws.gov/r9endspp/i/b/msab0h.html
Bald Eagle (Endangered Species) Wildlife Species information
http://www.fws.gov/r9extaff/biologues/bio_eagl.html
Bald Eagle Recovery USFWS Rock Island
http://www.fws.gov/r3pao/rock_is/activity/endangrd/eagle.html
Pollution and Biomagnification
http://www.ies.wisc.edu/partners/ALC-SCB/wiscbiod/BIOMAGNI.HTM
Env 440- Lecture 25
http://jan.ucc.nau.edu/doetqp/courses/env440/lectures/lec25/lec25.html
Bird Recovery Rates after DDT ban
http://www.edf.org/pubs/NewsReleases/1997/Jun/e_ddtRecovery.html
(Per group of 2-3 students)
Pen or pencil
Highlighter marker
Handout: 1 sheet notebook paper
1 sheet graph paper
VOCABULARY
endangered species - term the government uses to describe a
species that is likely to become extinct, unless humans intervene
threatened species - a species that may become endangered,
unless humans protect it. This species is less likely to become extinct.
biomagnification - the increase in concentration of a chemical
from one link of a food chain to the next
extinct - no longer surviving as a species
fledgling - a young bird that has successfully flown from
the nest.
PRE-VIEWING ACTIVITIES
At the start of class, ask students to answer the following
question: "Which animal is the symbol of the United States?
(the bald eagle) What do you think it would mean to Americans if our
national symbol disappeared?" (accept all responses) Say, "Today
we are going to investigate how the Bald Eagle nearly became extinct. Can
anyone tell me what extinction is?" (A species is considered extinct
if it can no longer reproduce. A population of birds, such as the Bald
Eagles of Texas, can also go extinct, if that area no longer contains
reproducing birds.) Say,"About 30 years ago, people noticed that the
Bald Eagles in our country were having problems reproducing. If a
species can't reproduce, how long can it survive?" (Only as
long as there are birds living.)
FOCUS FOR VIEWING
Say, "Today we are going to find out why the Bald
Eagle began to die off." To give students a specific responsibility
while viewing, say, "While we are watching the video tape, please
listen for the answer to this question: What happened to the
population of the Bald Eagle by the late 1960s?"
VIEWING ACTIVITIES
Begin tape Interactions-- Real Math, Real Careers:
Endangered Species after the opening credits, where the video shows an image of
a bald eagle flying. Audio is "The Bald Eagle has
been called, "lion of the sky." They are a fierce species."
To allow students an opportunity to record their answer, pause the tape
after the audio, "By the late 1960s, we were down to 400 pairs
nationwide." Video is the words BIG PICTURE next to a drawing of an
eagle. Tell the students that some scientists estimate the original number
of bald eagles in the continental United States as 75,000. Say, "Can
anyone think of a reason why a species would drop so dramatically?"
(Accept all answers.) Say, " Listen for three reasons why the
bald eagle population decreased." Resume tape.
Pause at the image of an eagle in close-up.
Audio is "... a harmful pesticide that was used during that period on farm
crops. " Review with students that the three main causes
for the eagles decline were illegal shooting, loss of habitat to development,
and use of the pesticide, DDT. Say, "Listen for what happens when
Bald Eagles get DDT into their bodies. Resume tape.
To allow students an opportunity to record their responses,
pause at the image of an eagle flying from a tree. Audio is "...the
egg breaks before the chick is old enough or mature enough to hatch on its
own." Say, "If most of the eggs were breaking, what do you think
would happen to the population of bald eagles? (Over time, as the remaining
eagles got older, the population should decrease, because very few birds were
born to replace them." Explain that by the early 1960s,
scientists had evidence that the pesticide DDT was the reason why these eggs
kept breaking. Eventually, DDT was banned in the United States.
Now the problem was to bring back the eagle, to help its population increase
across the United States. Say, "In the next segment of
this tape, listen for the meaning of the word "fledging". Then
listen for three things that can prevent a bird from fledging. "
Fast forward tape to the image of Robert Mesta,
wildlife biologist. Audio is, "Fledging is the simple act of a young
bird being strong enough to fly away from the nest." Pause at
the audio, "It can't be counted in the effort to recover a species."
Say, "Why can't you count the number of birds that hatch? (Because if
it doesn't survive, it can't reproduce and continue the species.) Say,
"Now listen to find out what productivity is, and what it has to do with
fledging." Resume tape.
Stop tape at the image of the formula Productivity =
number of fledges divided by the number of nests. Audio is, "If you
had a population of 20 nests, you'd have 30 fledgling in a year."
Say, what does this productivity number tell us?" (The higher the
number, the more fledgling birds being produced at each site. If this
number is high, we know the birds are reproducing successfully, and the species
is surviving.)
POST VIEWING ACTIVITIES
Subdivide the groups of students into groups of 2 or 3.
Say, "Now that we've found out a little bit about the bald
eagle's history, we are going to explore this topic in greater depth.
Let's see for ourselves how well the species is doing in the continental United
States (all states except Alaska and Hawaii), and how DDT caused such damage to
its population. We are going to use the internet to gather some
current data about the bald eagle." Pass out the handouts,
"No Longer in Danger?" Each group should have one question
sheet to answer. If necessary, show students how to locate a web site by
pulling down the "Bookmarks" or "Favorites" menu. Ask
students to use the web sites (listed in materials) to locate the information on
their sheets. (If the number of computers with internet access is limited,
you may choose to do either of the following: Have half of the class use
the internet, while the other uses other library resources, such as
CD-ROMs and magazines to find current information about the topics.
Alternatively, print out these web pages on plague and do this activity as a
classroom exercise.)
When students have completed their research, ask them to
present what they have learned in the form of a poster that uses only drawings
and symbols. Then ask representatives from each group to present their
findings to the class. To give students a specific responsibility during
these presentations, pass out the handout "Extinction Stinks! Note-taking
guide," and ask students to fill in the notes as each topic is presented.
Pass out the handout-- "I want to live!", and ask
students to download the web pages listed in this worksheet.
(Alternatively, provide copies of the information in this web site.)
In this activity, students will use current data to calculate the productivity
of Bald Eagles in different regions of the United States. As
mentioned in the video, productivity is the ratio of successfully reared young
to nests. Successfully raising offspring is one of the measurable
goals of the recovery plan for the bald eagle. Ask your students if all
populations of bald eagles are as successful at raising their young. Which
part of the country has had the most success? Which part of the country
has been least successful? What might be some factors causing these
differences? (The biggest difference is probably loss of suitable habitat.
As humans increase in population, and urbanize previously rural areas, isolated,
fish-filled streams are becoming more and more rare. As a result, the bald
eagle population remains small.)
ACTION PLAN
1. Contact your local office of the US Fish and Wildlife
Service, and request their endangered species trunk. This trunk contains
many items made from the fur and skins of endangered species and gives students
a representation of the major sources of the decline of many mammals.
2. Invite a wildlife biologist from your state's parks
and wildlife office to visit your class, and update you on the unique and rare
plants and animals in your area. You may wish to ask him or her to
describe the major threats to these species.
EXTENSIONS
Biology
Learn about estrogen mimics-- chemicals that may take the place
of our body's natural hormones. How might they affect reproduction?
How are they linked to endangered species? Find out by visiting the
following web sites:
American Scientist article: Environmental Estrogens (part
1 only)
http://www.amsci.org/amsci/articles/96articles/McLachla-1.html
Literature
Read the book that started the endangered species movement!
"Silent Spring," by Rachel Carson, describes how DDT could change the
world.
"NO LONGER IN DANGER?"
Copy and cut up these pages so that each group has a specific
topic to research
GROUP 1
Use the bookmarks on your computer to find the web site,
"Bald Eagle, Haliaeetus leucocephalus"
Print out a copy of this web site. Take turns reading the
information in these pages to your lab partners. Highlight the sentences
in the passage that answer the following question: List
four special things about the lifestyle of bald eagles that could affect how
successful these birds are at raising their young.
1.
2.
3.
4.
When you are finished, take turns creating a wordless diagram
that answers the question listed above. Make sure your diagram is
complete! It will be used to teach others what you have learned!
GROUP 2
Use the bookmarks on your computer to find the web site
"Bald Eagle Species Account."
Print out a copy of this web site. Take turns reading
the information in these pages to your lab partners. Highlight the
sentences in the passage that answer the following question: What
were four things that led to the bald eagles decline?
1.
2.
3.
4.
When you are finished, take turns creating a wordless diagram
that answers the question listed above. Make sure your diagram is
complete! It will be used to teach others what you have learned!
GROUP 3
Use the bookmarks on your computer to find the web site,
"Bald Eagle (Endangered Species) Wildlife Species information."
Print out a copy of this web site. Take turns reading the
information in these pages to your lab partners. Highlight the sentences
in the passage that answer the following questions: How did the bald
eagle population change between 1782 and 1960? What were two methods scientists
used to increase the numbers of eaglets? How has the number of bald
eagles changed from 1960 to today?
1.
2.
3.
4.
When you are finished, take turns creating a wordless diagram
that answers the questions listed above. Make sure your diagram is
complete! It will be used to teach others what you have learned!
GROUP 4
Use the bookmarks on your computer to find the web site,
"Bald Eagle Recovery USFWS ROCK Island"
Print out a copy of this web site. Take turns reading the
information in these pages to your lab partners. Highlight the sentences
in the passage that answer the following questions: What were the
criteria that needed to be met so that bald eagles could be removed from the
endangered species list?
1.
2.
3.
4.
When you are finished, take turns creating a wordless diagram
that answers the question listed above. Make sure your diagram is
complete! It will be used to teach others what you have learned!
GROUP 5
Use the bookmarks on your computer to find the web site,
"Pollution and Biomagnification."
Print out a copy of this web site. Take turns reading the
information in these pages to your lab partners. Highlight the sentences
in the passage that answer the following questions: How are
chemicals like DDT magnified in a food chain? Describe the process in four
steps.
1.
2.
3.
4.
When you are finished, take turns creating a wordless diagram
that answers the question listed above. Make sure your diagram is
complete! It will be used to teach others what you have learned!
GROUP 6
Use the bookmarks on your computer to find the web sites,
"Env 440- Lecture 25"
Print out a copy of this web site. Take turns reading the
information in these pages to your lab partners. Highlight the sentences
in the passage that answer the following questions (Hint: only the 2 last
pages of this site is important!) Answer the following questions:
How do chemicals like DDT build up in animals? How much DDT
was there in the water of lake Kariba? How much DDT was in a plant eater?
How much DDT was found in a meat eater?
1.
2.
3.
4.
When you are finished, take turns creating a wordless diagram
that answers the questions listed above. Make sure your diagram is
complete! It will be used to teach others what you have learned!
I want to live!
Name_____________________________
Calculate productivity for populations of bald eagles
When scientists realized that the bald eagle was in danger of
becoming extinct, they met to write a recovery plan. When the bald eagle
had come back in large enough numbers and its population, it would be removed
from the list. In 1995, the bald eagle was removed from the
endangered species list. This means scientists feel there are enough
eagles to continue the species. How did the bald eagle go from nearly extinct to
much more safe? Find out!
1. Use your bookmarks/favorites menu to locate the web
pages "Bird Recovery Rates after DDT ban" and
"Bald Eagle Recovery USFWS Rock Island." Print out a copy of
these sites, and use the data and diagrams in these printouts to answer the
following questions about the recovery of the bald eagle.
2. Use the Bird Recovery Rate page to find the data for
your state (or a neighboring state). Write down the lowest and highest
number of bald eagles found in your state.
state low ______________
state high ______________
3. Use a proportion to calculate the increase in bald
eagles in your state.
Example: If 3 eagles were found in your state in 1966
and there are now 300, the eagle population has increased 100 times, or
100-fold.
That is,
number of eagles today = 300 =
100-fold increase
number of eagles then
3
4. One of the goals of the Bald Eagle Recovery
plan was discussed in the video you watched earlier. Scientists wanted to
see an increase in productivity for bald eagles. Productivity is a ratio
that compares the number of nests with the number of eaglets that leave the
nest. In other words, this ratio answers the question, "Are the birds
that hatch surviving?" Look in the Bald Eagle Recovery page for a
data chart that shows the occupied territories and number of young produced for
each region of the U.S. Calculate productivity for each region by
using the following formula:
productivity = number
of young produced
number of occupied territories
Pacific region productivity = __________
Southwestern region productivity = __________
Northern region productivity = __________
Southeastern region productivity = __________
Chesapeake region productivity = __________
5. What might account for the smaller number of
territories in the Chesapeake and Southwestern regions of the US?
6. Make a prediction about how the number of
territories in the US may change over time. Explain the reasoning for your
prediction. How might this change affect the total number of bald eagles
in the U.S.?
Extinction stinks! Note taking guide Name_________________________
As your classmates present information about the decline and
recovery of bald eagles, fill in this note taking sheet!
What is special about the lifestyle of bald eagles that could
affect how successful they are at raising their young?
1.
___________________________________________________________
2.
___________________________________________________________
3.
___________________________________________________________
4.
___________________________________________________________
What were four things that led to the bald eagles decline?
1.
___________________________________________________________
2.
___________________________________________________________
3.
___________________________________________________________
4.
___________________________________________________________
How are chemicals like DDT magnified in a food chain?
Describe the process in four steps.
1.
___________________________________________________________
2.
___________________________________________________________
3.
___________________________________________________________
4.
___________________________________________________________
How much DDT was there in the water of lake Kariba? How
much DDT was in a plant eater? How much DDT was found in a meat eater?
1.
___________________________________________________________
2.
___________________________________________________________
3.
___________________________________________________________
4.
___________________________________________________________
What were the criteria that needed to be met so that bald
eagles could be removed from the endangered species list?
1.
___________________________________________________________
2.
___________________________________________________________
3.
___________________________________________________________
4.
___________________________________________________________
How did the bald eagle population change between 1782 and
1960? What were two methods scientists used to increase the numbers of eaglets?
How has the number of bald eagles changed from 1960 to today?
1.
___________________________________________________________
2.
___________________________________________________________
3.
___________________________________________________________
4.
___________________________________________________________
Updated: April 01, 2008
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