THE SILENT INVASION!
Species that are taking over right under our noses
and what you can do about it!
Before we begin….
HOW
MANY
OF
YOU…..




Have heard the term “invasive species”
before?
Feel like you could define what an
invasive species is?
Could give an example of an invasive
species?
Could explain how invasive species are
harmful?
So what is an invasive species?

The federal government definition:
 An
"invasive species" is defined as a species that is:
 1) non-native (or alien) to the ecosystem under
consideration and
 2) whose introduction causes or is likely to cause
economic or environmental harm or harm to human
health.

Invasive species can be plants, animals, and other
organisms (e.g., microbes). Human actions are the
primary means of invasive species introductions.
Does Non-Native = Invasive?

Out of place organisms
 Each
place has its own unique ecological system. In its
native setting, an organism is an integral part of
maintaining balance in the ecosystem.

Upsetting the balance
 When
put in to a new area, the previously harmless
species can cause damage to the new ecosystem it has
been introduced to.
Why should we worry?

Invasive species have many types of impacts:
Economic
Impacts
Infrastructure Impacts
Ecosystem Impacts
Human Health Impacts
Economic Impacts

Weeds, agricultural pests, plant pathogens and
control programs for invasive animals cost the U.S.
137 billion a year!
 Weeds
take up space crops could be grown in
 Pests like soybean rust actively kill crops
 Build ups of weeds like buffel-grass pose a fire danger
and have to be removed
 Economies dependent on recreation suffer when an
area become undesirable due to invasive species
A buffel grass fire being put out by an NPS firefighter and a lake in Michigan
completely choked by aquatic weeds.
Infrastructure Impacts

Aquatic species are the worst offenders- we all
need water, and it is needed for manufacturing and
power production
 Aquatic
invasive species like the zebra and quagga
mussel can clog intake pipes on dams and irrigation
systems
 Hydrilla and other invasive aquatic plants can clog
boat engines and jam steering columns
 The sheer weight of some aquatic invasive colonies can
sink a dock or other floating structure
A pipe clogged with quagga mussels cut open
Boat propeller completely disabled by hydrilla
Ecosystem Impacts




Aquatic invasive species change the concentration
of filtrates and dissolved oxygen in the water
Invasive plants can alter soil composition and
compete for light
Invasive animals alter the food web in an ecosystem
Invasives with no predators proliferate out of
control
The impact of the invasive zebra mussel on the Lake Michigan ecosystem
Human Health Impacts

New organisms bring with them new diseases and
pathogens!
 The
West Nile Virus and Avian Flu are considered to be
invasive microbes
 With the prevalence of global trade and travel, more
could be coming!


Invasive plants “weeds” cause allergies in many
people
Invasive aquatic filter feeders increase the amount
of toxins
West Nile is one of many “invasive microbes”
How are invasive species spread?
Commerce
Recreational
Activities
Landscaping
Pet
trade
Purposeful Introduction
Commerce


International shipping
brings invasives along
for the ride in ballast
water or attached to
cargo containers
Trains pick up debris
and material and
spread them to new
locations
Recreation



Boats can carry invasive
species in a number of
ways
Trailers can also easily
pick up and spread
material
Even something as small
as mud on your hiking
boot could spread an
invasive!
Landscaping


Be careful when you
choose plants- many
plants once used for
landscaping have
become invasive
Soil, sand and grass
seed that has not been
properly cleaned
spreads weeds
Pet trade


Many aquatic weeds
started out as
aquarium plants that
were released in to
the wild when people
“dumped” their tanks
irresponsibly
People have also
released some pets in
to the wild
Purposeful Introduction
Ooops!




Some invasives were thought to be
useful at first, then spread out of control
Many invasive plants began as
intentional landscape or erosion control
plants
Many invasive fish were originally
stocked as game fish
Other invasives were introduced to
control some problem, then became the
problem themselves!
What is being done?

Government Programs
 Task
Forces, Councils, & Committees- for individual
species multi-agency task forces are often formed to
assess and attack the threat
 Research Units and Labs- Government agencies and
universities have developed labs to specifically
research individual invasive species
 Eradication Programs- once a lab has identified and
tested a strategy, full scale programs are launched,
often in government resource areas first
What can I do?

LEARN- find out what is invasive in your area and
what is being done about it
 The
National Invasive Species Information Center can
connect you to state and local resources

DON’T PACK A PEST Don’t
bring fruits, vegetables, plants or animals when
traveling
 Inspect all of your recreational vehicles and gear
More ways to help
SOURCE LOCALLY Use
certified “weed-free” firewood, hay, mulch, sand
and soil
 Try to buy the above materials as locally as possible
(50 mile radius)
 Remove invasive plants from your yard or garden and
try gardening with native plants

VOLUNTEER- join in on organized efforts to remove
invasive species from natural areas
What are some examples of invasive
species?
The internet is
a powerful
ally- use it to
find out
specifically
what is
invasive in
your area!

Some major ones that are U.S.- wide
and known by most:
 Kudzu
Vine
 Starlings
 Killer Bees
Colorado River’s
TOP 10 MOST UNWANTED
New Zealand Mud Snail




From New Zealand
Introduced through ballast water
or game fish stocking in the
Snake River in Idaho. Also can
be spread on sport fishing
equipment.
Mollusk- tiny, tough, born
pregnant! Burrows in the
sediment and feeds on detritus.
Displaces and competes with
native invertebrates. Up to
500,000 can cram in a square
meter. Harmful to sport fisheries.
Salt Cedar (Tamarisk)




From Eurasia
Introduced as an ornamental
plant in the 1800’s.
Deciduous shrub- can spread
vegetatively or by seeds. Has an
extremely long taproot that can
reach deep in to the water table.
Absorbs large amounts of water
and creates large deposits of
salt. Dense thickets of salt cedar
and its intense thirst crowds out
native plants
Tamarisk along the shores of the Glen Canyon portion of the CO River.
Tiny New Zealand Mud Snails with a dime shown for scale.
Giant Salvinia




From Brazil
Introduced by the aquarium
trade in the 1990’s.
Floating tropical water fernhas strands that attach to
each other rather than
attaching to the soil.
Forms dense mats that block
sunlight and reduce oxygen
levels. Restricts other aquatic
plants from growing. Covers
entire lakes and ponds so that
migratory birds can’t land.
Quagga Mussel




From the Dneiper River in the
Ukraine
Introduced through the ballast
water of transatlantic shipping
vessels.
Mollusk- attaches on to hard
surfaces and filter feeds.
They are extreme water/food
filters removing large amounts of
plankton. They also take in lots
of pollutants which harm wildlife
that eat them. Colonies can clog
water-intake pipes and weigh
down docks and other structures.
Giant Salvinia floats in a pond.
A buoy covered with Quagga Mussels at Lake Pleasant.
Bullfrog




From Central and Eastern U.S.
Accidentally introduced
during trout stockings in the
1900’s. Also introduced
through the aquarium trade
and for pest control.
Amphibian- lives on the edges
of permanent water bodies
but can travel overland when
the weather is moist. Eats any
animal it can overpower and
fit down its throat!
Competes with and preys on
native species. Its dietary
range can reduce biodiversity.
Russian Olive




From Eurasia
Introduced as an ornamental
plant in the late 1800’s.
Thorny Shrub- produces a
small orange red fruit. Can
fix nitrogen in its roots so it is
able to grow on bare rock
and soilless areas.
Crowds out native species.
Grows close to river banks
and can snag and flip rafts.
Russian Olives along a river bank.
A bullfrog waits for its next meal.
Hydrilla




From Africa
Introduced by the aquarium
trade in the 1960’s.
Aquatic Weed- grows in
sediments up to two meters
deep. Grows in clusters of
long stems with tiny leaves on
them.
Crowds out native plant
species. Can fill an entire
lake or pond restricting water
flow and making boating
difficult.
Crayfish




From Canada and Central
U.S., Australia (Red Claw)
Found outside its native range
in the 1960’s- thought to be
spread by anglers who use it
as bait.
Freshwater crustaceanresembles a small lobster.
Crayfish live in rocky
freshwater areas and eats
whatever it can.
Competes aggressively with
native crayfish. Where there
are no native crayfish the
population quickly
proliferates out of control.
A Northern Crayfish in a bait bucket.
Hydrilla looks like a small harmless plant.
Eurasian Watermilfoil




From Eurasia
Introduced by the
aquarium trade in the
early 1900’s.
Aquatic Weed- grows
submerged in slow moving
water. Has long stems and
tiny leaves.
Crowds out native species.
Creates dense mats that
can interfere with
recreational activities.
Asian Carp




From Eurasia
Imported for aquaculture
in the 1960’s
Freshwater fish- they are
filter feeders not bottom
feeders like their cousins
the Common Carp. These
fish are a prized food fish
in Asia but are not eaten
here in the United States.
Competes with native
species for food and living
space. Jumping carp can
also injure recreational
boaters.
A pond clogged with Eurasian Watermilfoil.
An Asian Carp swimming in a shallow stream.
DO YOUR PART- STOP THE
INVASION!