The problem of introduced and exotic species is not country specific.
It is a problem all over the world and it has a heavy impact. Ballast
water from ships, soil from the soles of shoes and other interesting
pests that use products as their host are all contributing to the
invasion of other countries from their native homeland. The global effect
is devastating to this fragile planet.
We have focussed on, mostly, domestic animalsí impact on the
Australian environment for this site, although plant, marine, birds and
reptile species also impact heavily. Bitou Bush from South Africa,
Lantana, Prickly Pear and Blackberry are examples of plants that have
been introduced into the Australian environment and have taken over in
the areas where they have been allowed to gain control. The European Carp
is now found to be in plague proportions in the inland waterways of
The Cane Toad was introduced to control an insect, the Cane Beetle,
which was destroying sugar cane crops; however they are now a major
problem. The Indian Mynah bird is a major problem for native birds and
smaller animals. Initially, there were only 12 pairs of these birds
introduced, but now the numbers are so great that they have fast become
one of the most common birds that can be seen in suburban areas. They
kill young native birds that are still in their nests in order to take
over that nest for themselves. They are extremely aggressive birds and
are, indeed killers.
Australia has some of the strictest quarantine laws to anywhere else
in the world. All wooden, plant, animal, soil and biologic imports are
thoroughly screened by the Department of Agriculture, Fisheries and
Forestry and the Australian Quarantine and Inspection
Service in order to prevent the spread of foreign
disease and exotic pests. Australia is free from diseases such as Rabies,
Mad Cow and Bovine Foot and Mouth, which is mainly due to the strict laws
and vigilance of these departments. The vast majority of airline flights
into Australia, from overseas, have the aircraft cabins and holds sprayed
with a pesticide just prior to landing.
Lizard injured (2).
ThinkQuest 2003.Approximately 20 species of mammals, 30 species of birds, 21 species
of fish, 5 species of amphibians (water born, but later live on the land
e.g. frogs), 500 species of invertebrates (animals without a backbone,
e.g. insects), and 1500 species of plants have been introduced into the
Australian environment since European settlement, and have multiplied
dramatically in the wild.
A feral animal is defined as a domesticated or tame animal that
escapes its domestic environs. These animals adapt and become wild and
aggressive and the top of the food chain. An exotic animal is one that
has been introduced into a new environment through a deliberate
placement. The exotic animals were generally useful as sources of food or
used for transportation.
The track record of extinction of native plants and animals in
Australia is one which is not at all one to be proud of. Much of this
extinction has been caused by the introduction of non-native species. It
is only due to the passion of some environmentally aware people that the
Greater Bilby has been saved from extinction.
Native flora and fauna will only have some chance of survival through
thorough education and awareness, teamed with a dedication in the actions
and eradication of the pest problems. It will be through this process
that the destruction caused by these animals and plants can begin being