File - Mrs. Sterling

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Important Types of
Species
Keystone
Species
What is it?
A species whose removal causes
an ecosystem to collapse
Examples:
The sea star Pisaster ochraceus, the
original keystone species, feeds
preferentially on mussels on
northeast Pacific rocky shores. By
doing so, the predatory sea star
prevents mussels from taking over
the entire shore and allows less
competitive species to persist, thus
enhancing local species diversity.
Other Keystone
species
examples
As keystone species, African Elephants stop the
progression of grassland to forest or thicket by
weeding out the trees and shrubs. Elephants
browse on these woody plants, yanking young
trees out by their roots or stunting their growth
by eating the growth points on their branches.
Even if a tree or two escapes the weeding, they
won't last long. Sooner or later an elephant will
push the plant over, yank it out of the ground, or
kill it slowly by prying away its bark.
Other Keystone
species
examples
Sea otters are a keystone predator because they
keep the sea urchin population in check.
Without sea otters, the sea urchins would
decimate the kelp forests, which are essential
nurseries and spawning grounds for a variety of
marine fish.
Indicator
Species
What is it?
An organism whose presence,
absence or abundance reflects a
specific environmental condition.
Examples:
The presence of
river otters
indicates a
healthy, clean
river system.
Other Indicator
species
examples
All amphibians are indicator species due
to their extremely thin skin. Chemicals
can easily diffuse into their bodies to kill
them and UV rays can cause cancer or
deadly mutations.
Umbrella
Species
Examples:
What is it?
An organism whose protection
provides protection for a variety
of other organisms.
As top predators, grizzlies
are especially vulnerable to
disturbances in their
habitat and food supply and
thus serve as an excellent
indicator species for the
"wildness" and the overall
health of the coastal
ecosystem. Grizzly bears are
also an excellent umbrella
species because they require
large home ranges.
Other Umbrella
species
examples
The Black Rhino - These iconic animals
serve as umbrella species for wilderness
conservation, in that protecting them also
safeguards numerous other species of
plants and animals.
Other Umbrella
species
examples
Both the mountain lion and gray wolf
have are great umbrella species because
by protecting these endangered
predators, their prey and habitat must
also be protected.
Flagship
Species
What is it?
An organism who has become a
symbol and leading element of a
conservation campaign
Examples:
Pandas are a flagship
species because they
elicit an emotional
response from people.
Other Flagship
species
examples
People feel very passionately about
efforts to save endangered flagship
species like whales and dolphins.
Other Flagship
species
examples
Other flagship species are considered
icons for our society and therefore are
protected.
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