M A D E B Y: R I YA , L AVA N YA , A D A I , P R A C H I , R U D R A

I N VA S I V E S P E C I E S

W H AT A R E I N VA S I V E S P E C I E S ?• Any Kind Of Organism that is not native to an eco system and causes harm to that

particular eco system • It does not have to come from another country but is considered invasive if it harms the

eco system

The cutthroat trout is native to the Great Lakes, but is a threat in Yellowstone because it competes with the native Cutthroat for habitat.

• Ships carry aquatic animals in their ballast water. • Insects can get into wood products are shipped around the world. • Some ornamental plants that are left in the wild can become invasive

species. • Some invasive species are intentially or accidentally released pets.

Most invasive species are spread unintentionally by human activities.

H O W D O I N VA S I V E S P E C I E S S P R E A D ?

W H Y D O I N VA S I V E S P E C I E S P O S E A T H R E AT ?

• It might not have any natural Predators and hence will breed and spread quickly and take

over an area. • Due to this, it could out compete native species

for food and other resources. • It could carry or cause a disease that could wipe

out or drastically decrease the Population of native wildlife

Changing Food Webs: By destroying or replacing that area’s typical food sources, it could change the diet of the native wildlife, causing another species

to spread, or it could compete with native wildlife for food. Decreasing Biodiversity: It could alter the diversity and habitat of the native

wildlife. For example: The Kudzu plant can reproduce quickly and can replace the biodiversity of that particular area with a monoculture of just Kudzu.

Changing the Ecosystem: In some cases, all this could lead to a change in soil chemistry, or increasing wildfires.

L O N G T E R M T H R E AT S

I N VA S I O N C U R V E

It shows how an invasive species spreading becomes less and less easier to control, and how the cost increases.

1. Prevention: Of course, the easiest way to manage invasive species is to prevent them from spreading in the first place.

2. Eradication: If an Invasive Species is spotted early enough, EDRR (Early detection and rapid response) is effective, but more costly than prevention.

3. Containment: If, however, an invasive Species is not noticed by the public early on, it will continue to spread and reproduce. Eradication at this stage is highly unlikely,

and the focus is then shifted to preventing the species from spreading to new areas. 4. Resource Protection and Long-Term Management: When a species becomes too

widespread to eradicate, the attention is then turned to protecting highly valued resources that might be damaged by this species, and to lower it’s population as

much as possible.

T H E F O U R S TA G E S O F M A N A G I N G I N VA S I V E S P E C I E S

S O M E WAY S T O E R A D I C AT E I N VA S I V E S P E C I E S

Manual Control: Destroying Nests, flooding, digging, pulling, removal of hosts. Works best on small populations.

Prescribed Fire: Controlled burns to wipe out population in that area. Chemical Control: Use of pesticides, insecticides, Fungicides.

Biological Control: Use of other animals or diseases. Usually, the animals come from the creatures native range, and must undergo a

period of observation to deem that they are not invasive as well. Cultural Control: Changing the forest structure to control invasive

species, or so that if invasion does occur, it will be limited.

THE BLACK RAT

• One Of The First Species To Be Completely Distributed By Man.

• Originated in Tropical Asia and reached Europe by 1st Century AD.

• Soon spread all across the world through ships meant for trade

• Thrives in rural, urban and Suburban areas. • Caused the bubonic plague (The Black Death) among

many other diseases, and is the cause of the rapid decline and even extinction of many birds and small

organisms.

T H E B L A C K R AT

T H E A S I A N T I G E R M O S Q U I T O

• It is native to Southeast Asia. • It has become one of the most widely spread

species, spreading to over 28 countries. • It was spread by- believe it or not-

international tire trade. Tires stored outside collect rainwater, and in humid places, this is

the ideal breeding spot for mosquitos. • It carries diseases like Dengue and West Nile. • It feeds 24 hours a day and closely

associates with humans.

A S I A N L O N G H O R N E D B E E T L E • Native to Japan and other neighboring

countries • First Detected in New York in 1996 • The most destructive period is in it’s Larval

Stage, it tunnels through the parts of trees in between the bark and the wood, and, in large numbers, can destroy the whole tree.

• It has now spread to California, Ontario and Parts of Europe, and threaten 30-35% of

trees on the Atlantic Coast.

T H E C A N E T O A D• Native to South and Central America • Introduced to Hawaii,the Caribbean, and the

Philippines to get rid of pests in Sugarcane. • It produced impressive results and was soon

shipped around the world. • Unfortunately, these frogs then began eating

any terrestrial animals they could fit in their mouths, which is saying something, since they

grow up to 30 cms long. • They also secrete toxins strong enough to kill

any animal they come in contact with. (Humans have died by ingesting their eggs)

T H E N I L E P E R C H• Native to freshwater rivers and lakes in

Parts of Africa • It was introduced to Lake Victoria in the

1950’s. • The population was kept in check for quite a

while through commercial fishing. • However, in the 1980’s, the population

exploded, causing the extinction of hundreds of native species.

• It caused a devastating impact due to having a voracious appetite of fish,

crustaceans, insects, and zooplankton.

C O T T O N W H I T E F LY• Native to India • Grow to be just a Millimeter long • However, they feast on 900 different

kinds of plants worldwide. • They are capable of transmitting

upwards of 100 different plant viruses • They now thrive on every continent

but Antarctica.

K U D Z U• Native to Japan • Introduced to USA in 1876 as a fast

growing plants that could help in preventing soil erosion.

• Since its introduction, Kudzu has been spreading across the U.S. at a rate as fast

as 150,000 acres annually. • This is due primarily to the fact that its

individual vines can grow upwards of a foot per day

J A PA N E S E K N O T W E E D• Brought to the western countries from Asia

during the Victorian Era to use as a decorative plant

• Today, it’s the most invasive non-native plant species in the UK, costing the country over a

billion pounds so far to eradicate. • The Japanese Knotweed spreads very easily,

and is immensely hard to eradicate. It also out-competes other native plants, and causes structural damage to roads, sidewalks, and

buildings.

C H E AT G R A S S• Also Called ‘Bromus Tectorum’ • Native to Europe and Asia • Today it is a problem all over USA and Canada • It is a major problem in the western USA, where it

can completely drive out certain species and cause fires.

• This is because, with low precipitation, the grass can dry out.

• So, it adds an abundance of fuel to wildfires. • Cheatgrass has smooth, multi-branched stem that

can reach 3 to 30 inches in height. • It also often produces dense monocultures with

around 10.000 plants per square yard.

WAT E R H YA C I N T H• The plant is native to South America. • It is now widespread in Asia, Africa, North

America, Australia, and the UK. • It was introduced to North America in 1884 • If the plant isn’t controlled, it can cover an

entire lake or pond. • This blocks sunlight, which is harmful to

organisms underwater, and prevents much oxygen from entering.

• This is breeding group for mosquitos, which increases the rates of malaria.

It might increase the fitness of the native wildlife through hybridization.

They could also form positive relationships with the native species.

It could also cause Positive Ecological change:- http://science.psu.edu/news-and-events/2011-

news/Carlo2-2011

A D VA N TA G E S O F I N VA S I V E S P E C I E S

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