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
Competitors-organisms both
cooperate and compete
•Birds of prey
•Live in forests on
the edge of fields
•Eat mice and
other rodents
•Nest in trees
Red-Tailed Hawk
Barred Owl
Disease and Parasites
 Diseases
and
parasites can
be dependent
on population
size and
habitat
Weather
Storms
Drought
Flooding
Heat/cold
Fires

Fires lead to
succession which
is a predictable
change in the
community over
time.
Available Habitat
 Human
activities play a
large role
 Development,
damming
rivers, clear
cutting forests.
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: