Abiotic and Biotic
Background information:
The Birds of Prey’s natural area hosts the largest concentration of nesting prairie falcons in
the world each spring and summer. The birds nest along the cliff above the Snake River,
and use the huge Townsend Ground Squirrel population for food. This prey species lives on
the flat land above the canyon. Each year, the populations of these two species change
from April through July.
Biotic – living elements of an ecosystem
Abiotic – nonliving elements of an ecosystem
Procedures:
1. Observe Graph A and answer the following questions
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What do you observe happening?
What do you notice about the Townsend ground squirrel population in April,
May, and June?
What do you notice about the ground squirrel population in July?
What do you think caused this? What might have happened to the squirrels?
What do you notice about the falcon population in April and May?
What do you notice happening to the falcon population in July? What do you
think caused this?
How do these populations seem to be related?
What might have caused the change?
2. Work with a partner at your group to examine Graphs B-E. Go through your responses to
the questions above.
3. Create a conclusion of what is happening with the ground squirrels and the falcons within
this ecosystem.
4. Focus only on the role of temperature. If the ground squirrels go into summer hibernation,
where would you find the falcons after they leave the area? Where would they obtain food?
What kind of prey species might they use?
5. Be prepared to share with the large group.
Conclusion Questions:
1. What are the abiotic elements within this scenario? What are the biotic elements within
this scenario? How do they interact with each other?
2. Do these elements help keep an ecosystem healthy? How?