Invasive Species and their impacts on the environment

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Invasive Species and their impacts on the
environment
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Kudzu (Pueraria montana var. lobata)
Kudzu History Kudzu was introduced to the
United States in 1876 at the Centennial
Exposition in Philadelphia, Pennsylvania.
Countries were invited to build exhibits to
celebrate the 100th birthday of the U.S. The
Japanese government constructed a beautiful
garden filled with plants from their country. The
large leaves and sweet-smelling blooms of kudzu
captured the imagination of American gardeners
who used the plant for ornamental purposes.
Florida nursery operators, Charles and Lillie
Pleas, discovered that animals would eat the
plant and promoted its use for forage in the
1920s. Their Glen Arden Nursery in Chipley sold
kudzu plants through the mail. A historical
marker there proudly proclaims "Kudzu Developed
Here." During the Great Depression of the 1930s,
the Soil Conservation Service promoted kudzu for
erosion control. Hundreds of young men were given
work planting kudzu through the Civilian
Conservation Corps. Farmers were paid as much as
eight dollars an acre as incentive to plant
fields of the vines in the 1940s.
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Kudzus Impact on the Environment
Love It, Or Hate It... It Grows On You!
While they help prevent erosion, the vines can
also destroy valuable forests by preventing trees
from getting sunlight. The kudzu invasion has
threatened biodiversity of wildlife in Shawnee
National Forest. Kudzu kills, smothers, and
suppressed other plants beneath its thickly
tangled masses of leaves and vines. It girdles
trees, breaks branches and even uproots entire
trees through the sheer force of its weight.
Kudzu forms extensive monotypical patches,
alternating or eliminating native plant
communities.
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Garlic mustard (Alliaria petiolata)
HISTORY Alliaria petiolata was first collected
in the USA in 1868 on Long Island, New York. It
has since spread to 30 eastern/midwestern states
and 3 Canadian provinces. Garlic mustard invades
forested communities and edge habitats where it
rapidly spreads and displaces native herbaceous
species. Displacement occurs rapidly, often
within 10 years of establishment.
(invasion of garlic mustard in a forest)
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Impacts of Garlic Mustard on the Environment
1. It dominates areas and displaces natives,
altering species composition.2. It decreases
fuel load for burns.3. Rich soils, disturbed
areas such as forests with fallen trees, habitat
edges such as roads or streams, and disturbance
from trails or agriculture can encourage
invasion.4. In North America, it invades wet to
dry-mesic deciduous forest and in the partial
shade of oak savanna, forest edges, hedgerows,
shaded roadsides, and urban areas. It
occasionally occurs in full sun. 5. It grows on
sand, loam, and clay soils, and has also been
found on limestone and sandstone substrates.6.
Its seeds can remain viable for 5 years.7.
Garlic mustard spreads exclusively by seed. Seeds
are spread mostly by floodwaters or on humans,
animals, and vehicles. Wind dispersal is minor.
and can grow preactically anywhere
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Cane Toad (Bufo marinus)
The cane toad, Bufo marinus, was introduced to
Australia by the sugar cane industry to control
two pests of sugar cane, the grey backed cane
beetle and the frenchie beetle. One hundred and
one toads arrived at Edmonton in North Queensland
in June 1935. Unseasonal breeding occurred almost
immediately, and within 6 months over 60,000
young toads had been released. B. marinus adapted
well to the Australian environment and spread
throughout coastal Queensland. The rate of spread
was accelerated by toads deliberately moved ahead
of the advancing front line. In the late 1930s
toads were introduced with government sanction
into about 11 sugar growing locations in northern
and central coastal Queensland. After this date
introductions were non-official. Foci in the gulf
country, notably at Normanton and Burketown, and
in northern New South Wales were started by toads
being deliberately released by people. By the
early 1980s the cane toad had invaded most of the
northeastern Australia
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Environmental Impact of the Cane Toad
They are environmentally challenging breeding
machines that have formed a daunting northbound
march since they crossed the Queensland/Northern
Territory border about 20 years ago.By any
stretch of the imagination, cane toads are
unpleasant in the Dry they keep their shelters
moist, sometimes through urination, males attempt
to copulate with literally anything and females
lay up to 50,000 eggs more than once a year. By
the end of the current 2000/2001 wet season, cane
toads are likely to be in Kakadu. Generally, they
will progressively shell shock an unsuspecting
environment, in particular they will come close
to wiping out native quoll populations, poison
large masses of goannas and disturb the food
supply of many native animals. Also, there
appears to be few predators for all life stages
of toads, mainly because of their poison glands
(which contains a steroid that affects heart
muscle, and thus kills whatever tries to eat
them).
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Wild Boar
History In the 17th century, Sus scrofa became
extinct in England and were subsequently
reintroduced from mainland Europe for farming.
The genetic status of Sus scrofa currently living
wild in Britain is undetermined. Hybrids between
domestic pigs and wild boar as well as various
sub species of European wild boar may make up a
component of the free-living population.
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Impact of the Wild Boar
With no natural predators in the UK, the
uncontrolled release of Sus scrofa into
agricultural land has raised concerns over damage
to crops and pasture as well as to land of
conservation interest and risks to public safety.
DEFRA (MAFF) have also recognised their potential
to pass on disease to domestic livestock. The
populations establishing in the wild are thought
to have escaped from captivity in licensed wild
boar farms and private collections.Cereal crops
have been found damaged, and pasture land
extensively uprooted enhancing erosion,
affecting soil fauna and facilitating invasion by
weeds. Sus scrofa are also held responsible for
some predation on lambs and possibly transmit
diseases to domestic pigs. Physical damage
includes debarking trees and causing a risk to
human safety, through road accidents and
confrontations with the public.
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Water hyacinth (Eichhornia crassipes)
History The Water Hyacinth was introduced from
its native home in South America to various
countries by well-meaning people as an ornamental
plant to the US in the 1880's to Africa in the
1950's spreading to the Congo, the Nile and Lake
Victoria also in India.
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Impact of the Water Hyacinth on the Environment
IMPACT The presence of Water Hyacinth disrupts
all life on the water. They clog waterways
preventing river travel, block irrigation canals,
destroy rice fields, ruin fishing grounds. By
shading the water, these plants deprived native
aquatic plants of sunlight and animals of
oxygenated water. As the mats decay, there is a
sharp increase in nutrient levels in the water,
which spark off algal growths that further
reduces oxygen levels.
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Hydrilla (Hydrilla verticillata)
HistoryThis plant is native to Africa,
Australia, and parts of Asia but was introduced
to Florida in 1960 via the aquarium trade. In the
1990s hydrilla is now well-established in the
southern states where control and management
costs millions of dollars each year.
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Impact of the Hydrilla
Hydrilla causes major detrimental impacts on
water use. In drainage canals it greatly reduces
flow, which can result in flooding and damage to
canal banks and structures. In irrigation canals
it impedes flow and clogs intakes of pumps used
for conveying irrigation water. In utility
cooling reservoirs it disrupts flow patterns that
are necessary for adequate cooling of water.
Hydrilla can severely interfere with navigation
of both recreational and commercial craft. In
addition to interfering with boating by fisherman
and waterskiers in recreational waters, hydrilla
interferes with swimming, displaces native
vegetation communities, and can adversely impact
sportfish populations. The economic impacts of
these water uses to real estate values, tourism,
and user groups can be staggering.
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ZEBRA MUSSEL

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ZEBRA MUSSEL

• They were introduced into the Great
• Lakes accidentally by a boat that was
• traveling across the ocean.
• They get into water treatment plants and
• power plants and clog up the system.
• They pile up on beaches after their death
• and if you step on one you can cut
• yourself.
• They feed on plankton and significantly
• reduce the food supply.
• They take the food, space, and oxygen of
• native species.
• They reproduce so rapidly that they
• outcompete other species.
• They hang onto native mussels and often
• smother them to death.

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Sea Lamprey

A fish that has been killed by sea lampreys.
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Sea Lamprey

• They were introduced to the
• Great Lakes when the Welland
• Canal in Niagra Falls was
• completed in 1829.
• They attach themselves to fish
• and feed on their blood and
• therefore kill the fish.
• Sea lampreys kill as many as 18
• kilograms of fish during their life
• cycle.
• They affect the fishing industry
• because the sea lampreys kill so
• many fish.

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Water chestnut (Trapa natans)
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• Water chestnut, scientific name (Trapa natansL.),
  is an annual aquatic plant, with both surfacing
  and submersed leaves. Surfacing leaves are
  triangular with toothed edges and an inflated
  petiole, or leaf stalk, and form a rosette on the
  water surface. Submersed leaves are feather-like
  each leaf is divided into segments that are
  whorled around the leaf stem.
• A true annual, water chestnut reproduces by
  overwintering seeds. Single-seeded woody fruits
  produced from pollinated flowers the previous
  year germinate in early spring. A single seed may
  give rise to 10 to15 plant rosettes. Each rosette
  can produce up to 15 to 20 seeds. Ungerminated
  seeds may remain viable for up to 12 years.
  However, most seeds probably germinate in the
  first two years.

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Water chestnut is a fierce competitor in shallow
waters with soft, muddy bottoms. Uncontrolled, it
creates nearly impenetrable mats across wide
areas of water. In South Lake Champlain, many
previously often fished bays are now inaccessible
and floating mats of chestnut can create a hazard
for boaters. This noxious plant also severely
limits the passage of light into the water, a
critical element of a well-functioning aquatic
ecosystem, reduces oxygen levels which may
increase the potential for fish kills, out
competes native vegetation and is of little value
to wildfowl.
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Water Chestnut invasion is especially problematic
in Lake Champlain
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In Lake Champlain, water chestnut currently
invades a range of 55 miles, extending from
Whitehall, New York in the south north to
Charlotte, Vermont. In Vermont, mechanical
harvesting and hand removal have been the main
means of water chestnut management. Experience
has shown that these methods can be successful at
controlling and reducing the infestation if
infested sites are targeted repeatedly for five
or more years. Since water chestnut overwinters
entirely by seeds that may remain viable for
years, repeated control is critical to deplete
seeds in the sediment.
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Multiflora Rose
Rosa multiflora
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• Method of Introduction Introduced from Japan in
  1886 as rootstock for cultivated roses, planting
  of multiflora rose was encouraged by the U.S.
  Soil Conservation Service beginning in the 1930's
  to curb soil erosion. The nursery industry also
  touted the shrub as a "living fence," to control
  livestock and create snow barriers along
  highways. It was promoted by wildlife managers as
  late as the 1960's as an excellent source of food
  and cover for wildlife.
• Effects Multiflora rose blooms in May or June.
  Individual plants may produce up to 500,000 seeds
  per year. The majority of seedlings emerge near
  the parent plant from which the seeds fell.
  Multiflora rose readily invades prairies,
  savannas, open woodlands, and forest edges. Where
  it grows in dense thickets, it replaces the
  surrounding vegetation.

• Chemical Control Manual application of
  herbicides on freshly cut stems has proven an
  effective means of control as it can destroy the
  root system and prevent re-sprouting.

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• Biological Control Biological methods exist to
  kill or damage multiflora rose. Rose rosette
  disease, a native virus vectored by a eriophyid
  mite (Phyllocoptes frutiphilus), can be fatal.
  However, it may infect native roses and plums as
  well as commercially important members of the
  rose family like apples, some berries, and
  ornamental roses.

• Mechanical Control In areas where multiflora
  rose is just beginning to invade, fire can limit
  its establishment. Scattered populations in
  high-quality areas can be effectively controlled
  by complete removal of the plants. All roots must
  be removed because new plants can grow from
  severed roots. Mowing with heavy equipment has
  proven effective, although non-selective.
  Follow-up monitoring is necessary because new
  plants may arise from root fragments or
  previously dormant seeds.

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Tree Of Heaven
Ailanthus altissima
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• AKA Tree-of-heaven, also known as ailanthus,
  Chinese sumac, and stinking shumac, is a rapidly
  growing, deciduous tree in the mostly tropical
  quassia family (Simaroubaceae).

• ECOLOGICAL THREAT/ Effects Tree-of-heaven is a
  prolific seed producer, grows rapidly, and can
  overrun native vegetation. Once established, it
  can quickly take over a site and form an
  impenetrable thicket. Ailanthus trees also
  produces toxins that prevent the establishment of
  other plant species. The root system is
  aggressive enough to cause damage to sewers and
  foundations. 

• BACKGROUND Tree-of-heaven was first introduced
  to America by a gardener in Philadelphia, PA, in
  1784, and by 1840 was commonly available from
  nurseries.  The species was also brought into
  California mainly by the Chinese who came to
  California during the goldrush in the mid-1800s.

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• HABITAT IN THE UNITED STATES Tree-of-heaven is a
  common tree in disturbed urban areas, where it
  sprouts up just about anywhere, including alleys,
  sidewalks, parking lots, and streets.

• Control Establishing a thick cover of trees
  (preferably native, and non-invasive) or grass
  sod will help shade out and discourage
  establishment of ailanthus seedlings. Targeting
  large female trees for control will help reduce
  spread of ailanthus by seed. The most effective
  method of ailanthus control seems to be through
  the use of herbicides, which may be applied as a
  foliar (to the leaves), basal bark, cut stump, or
  hack and squirt treatment.

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Asian Long-horned Beetle
Anoplaphora glabrpennis
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• Method of Introduction The asian longhorned
  beetle (ALB), Anoplophora glabripennis
  (Motschulsky), is believed to have been
  introduced into the USA in 1996 from China. It is
  believed that ALB was brought over in solid wood
  packing materials such as pallets and crates from
  China.

Threat This non-native beetle poses a threat
to urban and rural forests. Larvae of the beetle
tunnel throughout the tree resulting in limb
breakage, dieback of the tree crown, and tree
death. It is not clear how much damage they could
cause but they have a very wide host range and
might cause significant die-offs of hardwood
trees.

• Other Effects A. glabripennis infestations of
  urban street and ornamental trees affects the
  esthetic human environment. Larval tunneling
  weakens the structure of the tree so that limbs
  and in some cases entire trees may collapse,
  posing a danger to pedestrians and vehicles (8).
  Property values will also likely decrease in
  areas where ALB spreads and kills trees (Haack,
  1997). Furniture, the maple syrup industry and
  fall color tourism may be affected if ALB can not
  be eradicated and spreads (4). A. glabripennis
  has an affinity for hardwood trees, which poses a
  risk to forest and tree resource industries by
  reducing the quality of lumber, veneer and wood
  fiber (1 Haack, 1997).

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• Efforts to Curb population US regulations state
  that solid wood packing should be free from bark
  and live plant pests (2). As of September 1998,
  solid wood packing from China must undergo
  treatment by heat, fumigation, or preservatives
  before entering any US port (8).

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European Gypsy Moth
Lymentria dispar
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Method Of Introduction A French naturalist
brought the gypsy moth to the United States
(Massachusetts) in 1869 for experiments. During
his studies some of the caterpillars escaped into
his garden and the nearby woods. This initial
small population quickly became a very serious
pest. Left alone, the Gypsy moth very quickly
became established throughout the northeastern
quarter of the United States.

• Effects Damage from early instar larvae may
  resemble shotgun holes in the leaf. As the larvae
  grow the holes will become larger and feeding
  will occur along the leaf margin. In the final
  instar stage the larvae will consume the entire
  leaf. Things looked grim in 1995. The gypsy moth
  was rapidly expanding into Virginia. Nationwide,
  approximately 1.4 million acres were defoliated,
  with Virginia accounting for 850,000 defoliated
  acres. With the large oak component in Virginias
  forests, prospects were bleak.

• Control A fungal pathogen Entomophaga maimaiga
  finally caught up with the moth. E. maimaiga was
  first observed in New England in 1989 and was
  experimentally released in Virginia in 1989. In
  1995 the moth populations crash in northern
  Virginia was largely attributed to the fungus.

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• Introduction Zebra mussels were introduced into
  the Great Lakes system in 1985 or 1986 and first
  turned up in Lake St. Clair.

• Effects High concentrations of zebra mussels
  were likely contributing to the low dissolved
  oxygen levels. Water clarity improved
  dramatically in some part of the Mississippi
  River in the late summer of 1997 which was likely
  influenced by the filter feeding activity of
  zebra mussels. Native mussels are being smothered
  by high concentrations of mussels that attach
  themselves to their shells. Zebra mussels have
  been known to clog the intake pipes in municipal
  water supplies, causing cities to have to shut
  off water until pipes could be unclogged.

• Control Most scientists believe that zebra
  mussels cannot be eradicated, so the goal now is
  to learn to control or accommodate them. Research
  is currently identifying economic incentives to
  prevent the further spread of zebra mussels and
  alternatives for preventing future introductions
  of other nonindigenous species.

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European Green Crab
Carcinus maenas
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• Method of Introduction native of the shores of
  Europe, the crab has been introduced to western
  North America, Australia, and South Africa all in
  the past two decades through transport in ballast
  water.

• Effects C. Maenas was spotted in Washington
  state (northwest corner of cont. US) just a few
  years ago, and the ecology of that area is such
  that it could decimate Washington's mollusk and
  oyster populations if it establishes itself.   

• Control option is the barnacle Sacculina
  carcini, which is specific to Carcinus. S.
  carcini is known as a parasitic castrator,
  because it makes the host sterile by attaching to
  the gonads and using them to incubate its own
  offspring .

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Red Imported Fire AntSolenopsis invicta

• RIFA colonies are extremely productive compared
  to other ant species, and grow rapidly. Worker
  ant densities can average up to 1500-3000
  ants/m2. Workers are armed with a powerful sting,
  which they use both for defense and to subdue
  prey.
• In infested areas, they threaten injury or death
  to livestock, pets, and wildlife. RIFA damage
  crops, ornamental plants, electrical equipment,
  and irrigation systems, and also cause serious
  declines in biodiversity. Since they are
  impossible to eradicate once established,
  repeated pesticide treatments are needed to
  maintain reduced ant numbers and protect human
  health. These treatments can be costly.
• The RIFA has not been too good for business,
  either. For commercial plant producers, the
  regulations associated with shipping infested
  material to uninfested areas add significant
  costs.
• In agriculture, the RIFA frequently invades
  soybean crops and heavy infestations yield fewer
  soybeans In Georgia and North Carolina, it has
  been reported that RIFA mounds caused direct
  interference with combine operation resulting in
  16.8 to 49.1 kg/ha of soybeans to not be
  harvested.
• It has also been reported that the RIFA could
  cause as much as 156.4 million dollars in losses
  for soybean crops.
• Opportunistic feeding on the young tender growth
  by red imported fire ant occurs throughout the
  year and can cause significant damage not only to
  soybean crops, but citrus, corn, okra, bean, etc.
  Monetary losses occur when RIFA interfere with
  the root system of the plant, mechanically
  disable combine operation, or feed on the young
  growth of plants.

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• The latest exotic species to invade the Great
  Lakes is a diminutive fish from the Black and
  Caspian seas area
• Their rapid spread was facilitated by the ballast
  water transfer from ocean-going ships in the
  Great Lakes. The presence of gobies in the
  Calumet River means that they have direct access
  to the Illinois and Mississippi river drainages,
  and thus to a large geographic range.

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• Round gobies are natural predators of zebra
  mussels and a substantial proportion of their
  diet in the Great Lakes is composed of zebra
  mussels. This suggests that round gobies probably
  will be able to invade many regions of the Great
  Lakes, and may displace native species by
  outcompeting them for shared resources of food
  and habitat.
• Gobies are able to deeply penetrate the
  interstitial spaces in cobble substrates and
  thus, they are effective predators of lake trout
  eggs
• Gobies have both the potential population
  densities and the appetite to pose a serious
  threat to lake trout reproductive success.

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Sea lamprey (Petromyzon marinus) are predaceous,
eel-like fish native to the coastal regions of
both sides of the Atlantic Ocean.

• They entered the Great Lakes through the Welland
  Canal about 1921. They contributed greatly to the
  decline of whitefish and lake trout in the Great
  Lakes. Since 1956, the governments of the United
  States and Canada, working jointly through the
  Great Lakes Fishery Commission, have implemented
  a successful sea lamprey control program.