Population Ecology
Ecologists are often interested in a population (a group of individuals of one
species that live in a particular area). Populations of many species fluctuate from
year to year. One of the best studied cycles of populations involves lynx and hares
in the northern US and Canada.
A)
Web site name: The Lynx and the Hare
Web URL: http://lynx.uio.no/jon/lynx/cglynx1a.htm
Read “The Lynx and the Hare”
1).
Why did the population of lynx crash in 1991/1992? ___________________
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2).
What is the price of a lynx pelt (fur) :
a) now ? _____________________
b) in 1987 ? _________________
3).
How big is the lynx’s home range? _________________________________
4).
What will lynx eat when the population of hares is low?
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5).
What role do plants play in the cycles of lynx population? ______________
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Click on “Continue…..”
6).
What is the longest distance that one lynx has traveled? ________________
7).
What are two differences between hares and rabbits? __________________
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8).
When hares are abundant, which lynx may share a home range?
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If the population of a species becomes very low, the federal government often tries
to protect the endangered species.
B)
Web site name: U.S. Fish & Wildlife Service
Web URL: http://nctc.fws.gov/resources/course-resources/es-slideshow/lrg/sld01.html
Read “Endangered Means There’s Still Time” (click on the arrow at the bottom of
each page to go through the pages).
9).
What is the difference between “endangered” and “threatened”?
Endangered: __________________________________________________
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Threatened: __________________________________________________
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10). When did the dusky seaside sparrow become extinct? ______________
11). Why did the dusky seaside sparrow become extinct?
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12). What is the main reason for species becoming endangered?
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13). What is “old growth”? ___________________________________________
14). Why are different aged trees important for owls? ______________________
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15). Where do whooping cranes feed? __________________________________
16). When did Florida first pass a law to protect manatees? ________
17). How many other species can be eliminated by a disappearing plant? ______
C)
Web site name: BBC News
Web URL: http://news.bbc.co.uk/2/hi/science/nature/4522044.stm
Read “Extinction alert”
18). Roughly how many species are on this list? ___________________
19). How much would it cost to protect some of the sites? _________________
Click on “Open” In Pictures to see some of these species. Give some information
on two of these species below:
20). Species: ____________ Information: _______________________________
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21). Species: ____________ Information: _______________________________
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22). How many sites contain at least one species classified as “endangered” or
“critically endangered”? ___________________
Click on “Open” to enlarge the map of Sites of Imminent extinction.
23). How many unprotected sites are in the US? _____________________
24). Which part of the world has the greatest concentration of unprotected sites?
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25). Which two species are being captive bred by Durrell Wildlife?
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26). How does the community benefit in Madagascar? ___________________
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D)
Web site name: U.S. Geological Survey
Web URL: http://www.mbr-pwrc.usgs.gov/bbs/guild/group98.html
Read “Patterns of Population Change in Birds”
27). How many bird species are covered by this survey? ___________________
Click on “controversial” and read “Are birds declining?”
28). Why is it hard to work out if a species is declining? ____________________
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Click the “Back” button on the top left of the screen. Scroll down to the “Maps of
Population Change”. Click on the appropriate “Trend Map” to find out if a
population is increasing or decreasing, or click on the “Species Richness Map” to
find out where in the country a group of bird species is most abundant.
29). Are Grassland birds increasing or decreasing in your state ? _____________
30). What part of the country has the most species of Grassland birds ?
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31). Are Wetland bird species increasing or decreasing in the southern half of
Texas? _______________________________
32). Are Open-cup birds increasing or decreasing in Florida? ________________
33). Which two states have the highest number of Permanent Resident species?
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34). What part of the country has the highest number of Neotropical migrants?
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In natural environments, species will increase or decrease in population for a
variety of reasons. The next website concentrates on birds in Hawaii.
E)
Web site name: U.S. Fish and Wildlife Service
Web URL: http://www.fws.gov/pacificislands/fauna/nukupuu.html
Read “Endangered Species in the Pacific Islands”
35). Look at the diagram of the Nuku pu’u. What is unusual about its beak?
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36). What does the Nuku pu’u feed on? _________________________________
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37). What is the estimated population of these birds? _____________________
38). What are reasons for the decline of native forest birds?
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Click on “Endangered species” then “Threatened and Endangered Species”. Pick
two different birds from the list.
39). Which bird did you pick? ________________________
40).
Describe the bird: ______________________________________________
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41). Summarize the “Habitat and Behavior” section: _______________________
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42). Summarize “Past and Present”: ____________________________________
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43). Which bird did you pick? ________________________
44).
Describe the bird: ______________________________________________
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45). Summarize the “Habitat and Behavior” section: _______________________
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46). Summarize “Past and Present”: ____________________________________
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Pick a different organism from the list (mammal, reptile, snail or plant)
47). What organism did you pick? _____________________________________
48). Summarize the information on this organism: ________________________
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