1. Limiting Factors
Environmental factors that affect an organism’s ability to survive in its environment
Can be biotic or abiotic
EX: food availability, predators, and temperature

2. Factors that limit one population in a community may have an indirect effect on another population
EX: lack of water limits growth of grass, which will reduce the population of mice, and then reduce the population of hawks

3. Ranges of Tolerance
The ability of an organism to withstand fluctuation in biotic and abiotic tolerance for environmental change
EX: Catfish can live in warm water with decreased oxygen, whereas bass cannot.

4. Density DEPENDENT Factors
As population increases so do these factors
Disease, competition, parasites, and food

5. Density INDEPENDENT Factors
affect all populations regardless of their density
Temperature, storms, floods, and drought

6. Video Clips TD VI
VOL RV

7. Discussion Questions
What happened to the wolf population as the necessary components (food, water, shelter) decreased?
Can you brainstorm some ways to stop the wolf population from crashing as the limiting factors change?