AP Environmental Science
Population Ecology - chapter 5 - section 5-3
I. Growth rates and carrying capacity
A. definition of a population

various distribution patterns – fig. 5-14
B. growth rate is determined several factors:
1. growth rate = (b + i) - (d + e). This rate is called the intrinsic rate
of increase, and is designated “r” in equations
2. the carrying capacity (“K”) of a population is the maximum
amount that can be sustained
3. factors that limit (environmental resistance) or enhance (biotic
potential) growth
C. Exponential growth – fig. 5-16
D. Logistic growth – fig. 5-16

Explore population dynamics with moose and wolves (using SimBio on
school computers) or this online interactive using lions
E. examples of growth curves – fig. 5-18, 5-B (sea otters)
1. density-independent growth occurs when population size is
determined by habitat disruptions. Populations growing in this
manner are called “r-selected”
2. density-dependent growth occurs when ecological relationships
determine population size. These populations are termed “Kselected”
3. comparison of r- and K- selected species

parental care is a characteristic
4. predators and prey sometimes cycle together – fig. 5-15 (lynx
and hare) and wolves and moose on Isle Royale | more on the Isle
Royale wolf
5. survivorship curves show the percentage of a population
surviving over time
F. sampling/recording population growth
1. census
2. estimating
3. capture/mark/recapture
4. counting evidence (scat, etc.) | check out some research on deer,
dragonfly, and other animal populations | video recording of
mountain lions in southern California
| MoveBank - a website for animal tracking experiments | Bear
DNA study in northern rockies