Australia's native plants and animals have adapted to life on an isolated continent over millions of years.

Since European settlement native animals have had to compete with a range of introduced animals for habitat, food and shelter. These pressures have also had a major impact on our country's soil, waterways and marine ecosystems.

In Australia, pest animals typically have few natural predators or fatal diseases and some have high reproductive rates. As a result, their populations have not naturally diminished. Pest animals can multiply rapidly if conditions are favourable.

Foxes and feral cats

Foxes and feral cats prey on a number of small to medium sized mammals, birds and reptiles. As a result, they have led to the decline in numbers or disappearance of a number of native species.

The most effective way of decreasing fox predation is through exclusion fencing and large scale baiting. To be effective, baiting must be ongoing and must consider the effects on native animals.

There is currently no effective technique for controlling feral cats on a broad-scale.

Rabbits

Rabbits compete with native animals for food and habitat, damage vegetation and expose soil to erosion. They ringbark trees and shrubs, and prevent regeneration by eating seeds and seedlings. Their impact often increases during drought and immediately after fire when food is scarce and they eat whatever they can.

The ecological changes caused by large numbers of rabbits may have contributed to the extinction of several small ground-dwelling mammals and to the decline in numbers of many native plants and animals.

Rabbits are most effectively managed by integrated programs involving warren ripping, fumigation and poison baiting.

Northern Pacific seastar

The Northern Pacific seastar rapidly colonised Port Phillip Bay after its first confirmed sighting in August 1995. It is thought that was introduced to Tasmania through ballast water from Japan and subsequently introduced into Port Phillip Bay.

The Port Phillip Bay infestation is unfortunately well established and has negative impacts on native species and marine industries. Measures to stop the spread of the seastar to other areas in Victoria are in place.

For more information see the Department of Sustainability and Environment website.

Exotic grazers

Exotic grazers (e.g. feral goats, horses, deer and pigs) are not as widespread as foxes, cats and rabbits. Their impacts on the natural environment are similar to rabbits.

Goats, deer and pig numbers are controlled by shooting. At some locations, programs which aim to eradicate local populations are in place.

Related links

• Department of Primary Industries
• Department of Sustainability and Environment
• Department of Sustainability and Environment - Marine pests