Disappearing Frogs - Research
Group Members:_______________________________________________________________________
Date:______________ Class Period_________
Using www.mylfrog.com
, students must answer the following questions:
Each question set is labeled with the name of the section in which it appears on the website.
Natural History:
1.
What are the two species that are considered mountain yellow-legged frogs?
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2.
What has this frog adapted to do that most other amphibians cannot?
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Distribution:
3.
In what two states do these frogs live? Where are they usually found?
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Life Cycle:
4.
How long does it take most frogs to develop from an egg to a tadpole and into a frog?
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5.
How long does it take the yellow-legged frog tadpoles to metamorphose (change) into frogs?
Why does it take so long?
Ecosystem Role:
6.
When the frog is a tadpole, what do they eat? Are they carnivores, omnivores, or herbivores?
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7.
When the frog is an adult, what do they eat? Are they carnivores, omnivores, are herbivores?
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8.
Why is the mountain-yellow legged frog so important to their ecosystems? Explain.
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Current Status:
9.
Recent studies have shown that these frogs are now missing from _____% of their natural locations in the Sierra Nevada, and ______% are missing from their localities in the Transverse
Ranges.
Threats:
10.
What is usually the main cause of amphibian losses around the world, but is likely only a minor factor in the loss of the yellow-legged frog?
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Disappearing Frogs (Continued)
Introduced fish:
11.
Why were the areas that the yellow-legged frog lived devoid of (missing) fish?
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12.
Where did the fish come from, and why were they added?
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13.
What evidence do we have that removing the trout would actually help the frogs?
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14.
Why are the trout such a problem for the frogs?
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15.
Why don’t the frogs grow in the small, shallow ponds without trout in them?
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Disease:
16.
What impact has the Chytrid fungus (chytridiomycosis) had on the frog populations?
17.
The last sentence in this section states: “Regardless of the mechanism, these persistent frog populations may well be the only hope for preventing the extinction of the mountain yellowlegged frog.”
Using what you know about natural selection, what do you think this means?
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Contaminants:
18.
What is the major contaminant affecting the yellow-legged frog populations? Where is it coming from?
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19.
Researchers are trying to determine if low concentrations of pesticides make frogs more vulnerable to what disease?
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UV Radiation:
20.
Why do researchers think that UV radiation is not a major factor in the decline of the yellowlegged frog?
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Conservation Efforts:
21.
What did the California Department of Fish and Game (CDFG) implement to help frog populations?
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