Nonnative Species Slideshow

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 “My heart is broken in the face of the stupidity of my species.”
Joni Mitchell
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 Native species are those that normally live and thrive in a
particular community. They occupy specific habitats
and have specific niches in their native environment.
They have natural predators that help to keep their
populations in check.
 Species that migrate
into an ecosystem or
are deliberately or
accidentally introduced
into an ecosystem by
humans.
 Can cause significant
ecosystem damage, due
to having no natural
predators in their new
ecosystem
Some Harmful Nonnative Species
in the United States
Fig. 9-11, p. 200
Deliberately Introduced Species
Purple loosestrife European starling
African honeybee
(“Killer bee”)
Nutria
Salt cedar
(Tamarisk)
Marine toad (Giant Water hyacinth
toad)
Japanese beetle
Hydrilla
European wild
boar (Feral pig)
Fig. 9-11a, p. 200
Accidentally Introduced Species
Sea lamprey
(attached to lake
trout)
Argentina fire ant
Brown tree snake
Eurasian ruffe
Common pigeon
(Rock dove)
Formosan termite
Zebra mussel
Asian long-horned
beetle
Asian tiger
mosquito
Gypsy moth
larvae
Fig. 9-11b, p. 200
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 In 1957, attempts were made in Brazil to cross
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African honeybees with native honeybees in
order to produce an overly aggressive bee –
hoping this would increase honey production
Several African honeybees escaped
Eventually, the native honeybees were
displaced through competitive exclusion and
migrated northward at a rate of 200 miles per
year.
The bees’ Northward migratory rate is
slowing down due to climate (frost).
Will global warming allow their migration to
move northward over time?
Problems: They are so aggressive, they not
only out-compete native bee populations,
but pose great health threats to humans.
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 In the late 1930’s , red fire ants were introduced by
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accident in Alabama
The ants were in shiploads of lumber and cargo that
were imported from South America
Interspecific competition (for resources) reduced
native ant species by 90%!
Fire ants are very aggressive and through direct
combat, reduced native species.
Since there are no natural predators, they produced
more colonies than native ants and increased their
population density significantly in the South.
 Interference Competition – fire ants consumed food
and invaded habitat of native ant species
(competitive exclusion principle – 2 species
competing for the same resources cannot coexist
sustainably).
 Fire ants release sulfuric acid when they bite and can
kill deer fawns, lizards, birds, livestock, pets, and
human babies.
 Fire ants have invaded trucks and caused roadside
accidents when drivers have been attacked.
 Fire ants chew through underground cables and
disrupt electric and phone services, and have started
electrical fires in the South.
 Fire ants are pesticide resistant
(Directional Natural Selection
of r-strategists)
 In an attempt to control the
fire ants, the USDA (US
Department of Agriculture)
introduced a non-native
parasitic fly that deposits eggs
on the fire ants. When the
larvae develop, they eat the
heads of the fire ant.
 ANARCHY!
(Degrees Celsius)
 In the 1950’s, the Brown Tree
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Snake arrived in Guam in the
wheel wells of airplanes from
Australia
One of the snake’s staple diets
is birds. Eventually, the snake
drove 85% of native forest birds
to extinction.
These snakes are highly
aggressive, nocturnal
predators.
There are no natural predators
of the Brown Tree Snake in
Guam.
These voracious eaters even
consume domestic animals,
and even small human babies!
 1930’s - imported from Japan and planted in the southeastern
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USA to help combat soil erosion following the Dust Bowl.
1940’s – US Soil Conservation Service (federal agency) paid
farmers subsidies to grow kudzu vine.
Problems: No natural predators, very prolific reproduction.
Presently, it costs the US government $500 million/year to
eradicate!
Possible Commercial Uses: Chemicals produced in the vine
are used in Japan to combat diseases.
USA found chemicals in vine may reduce alcoholic cravings.
May be a source for paper products!
Kudzu Taking Over an Abandoned
House in Mississippi, U.S.
Fig. 9-12, p. 201
 In 1869, a French naturalist
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imported gypsy moths to Boston
in an attempt to breed them with
silkworms.
Gypsy moth caterpillars escaped
during the experiment.
These moths eat the foliage of
many hardwood trees, especially
oaks and cherries.
They continued to “hitch hike”
rides via cargo into the USA.
The current gypsy moth
population can eat all of the
leaves on 13 million acres of trees
in 1 growing season!
 The beetle is native to China.
 In 1996, the beetle was found in New York City and Amityville, Long
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Island.
They were believed to have arrived in the US from cargo pallets imported
from China.
Target trees: Norway, sugar, silver, and red maple.
Will also feed on horse chestnut, poplar, willow, elm, mulberry, and black
locust.
Eradication method: Must cut down, chip, and burn the trees.
New Method: in Central Park, New York City - the Parks Department
injects “birth control” via hypodermic needles into the base of hardwood
trees so that when beetle females feed on the trees, will become sterile
This has significantly reduced the population in Central Park
Problem: Costs a lot of $ and requires many employees to administer and
monitor populations.
Presently, the New York City Parks department exists on a shoe-string
budget!
Common
Reed
Phragmite
s australis
 “ By reducing and degrading life’s support systems (Earth
Natural Capital), we could make our own species more
vulnerable to extinction, or at least to a massive
population crash”.
 If we are the most “intelligent” species on Earth, why
can’t we follow the simple laws of nature?
 Education
 Participate in local groups to conserve the biological
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integrity of ecosystems
Promote local economic growth while thinking globally
Refuse, Reduce, Reuse, Recycle
Shop locally, think globally (be an educated consumer)
GET INVOLVED AND TELL A FRIEND
What Can You Do? Controlling Invasive Species
Fig. 9-14, p. 203
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