Ecosystems
Limiting
Factors
Let’s suppose….

We have two mice…:
and they
produce the
standard 56
“pups” (baby
mice) each
year.
and each of
these mice goes
on to have 56
babies each
year….
Soon…..

We’d be over-run with mice on the planet!!
Why doesn’t this occur?
Limiting Factors

A limiting factor
is an abiotic or
biotic factor that
restricts the
number of
individuals in a
population.
Limiting Factors

1.
Limiting factors can
include:
Competitors
Limiting Factors

1.
2.
Limiting factors can
include:
Competitors
Disease and
parasites
Limiting Factors

1.
2.
3.
Limiting factors can
include:
Competitors
Disease and
parasites
Weather
Limiting Factors

1.
2.
3.
4.
Limiting factors can
include:
Competitors
Disease and
parasites
Weather
Fires
Limiting Factors

1.
2.
3.
4.
5.
Limiting factors can
include:
Competitors
Disease and
parasites
Weather
Fires
Available habitat
Limiting Factors

1.
2.
3.
4.
5.
6.
Limiting factors can
include:
Competitors
Disease and
parasites
Weather
Fires
Available habitat
Predators
1. Competitors-competition results when
organisms struggle to survive in a habitat
with limited resources
•Birds of prey: live
in forests on the
edge of fields
•Eat mice and
other rodents
•Nest in trees
•Live in same
Red-Tailed Hawk habitat, use same Barred Owl
resources, so they
compete with each
other
2. Disease and Parasites


Diseases and
parasites can be
dependent on
population size and
habitat
Larger population =
more parasites and
disease = limit how
big population gets
3. Weather
Storms
Drought
Flooding
Heat/cold
4. Fires

Fires lead to
succession which
is a predictable
change in the
community over
time.
5. Available Habitat



Human activities play a
large role
Development (homes,
buildings, parking lots),
damming rivers, clear
cutting forests, hunting.
Parts of the habitat can
also be limiting: amount
of food(prey), available
nesting sites
6. Predators
 Predator-prey
relationship can
be a delicate
balance
between the
two
populations.
Predators

As the prey
population
increases, the
predator population
increases. As the
prey population
decreases, then so
does the predator
population.
Example: Lynx and Hare:
What is Carrying Capacity?

Because of these limiting factors, each
ecosystem has a finite capacity for growth
connected to its carrying capacity.
What is Carrying Capacity?

Carrying capacity is
the maximum number
of individuals of a
species that an
ecosystem can
support.
Limiting Factors of the Cedar
Glade Activity



In nature, populations of organisms rarely
grow uncontrolled. Each ecosystem has a
carrying capacity (or number of organisms it
can sustain/support).
Remember, limiting factors are biotic and
abiotic factors that prevent the continuous
growth of a population.
Because of limiting factors, the number of
organisms in a population is often well below
carrying capacity.
Limiting Factors of the
Cedar Glade Activity

This activity will look at limiting factors found in
the Cedar Glade ecosystem, and their impact on
population growth.
The details of the activity…