What are invasive animals? Understand their impact on ecosystems

Animal	Origin	Invasion	Impact
European rabbit	Europe	Australia	Destroy vegetation, leading to a decrease in native plant species
Asian carp	Asia	North America	Compete with local fish food and affect water ecology
American blue snake	North America	Australia	Prey on local birds and reptiles, affecting local species
Red-bellied squirrel	North America	United Kingdom	Compete for food resources and threaten local squirrel populations
Big-headed snake	South America	Galapagos Islands	Predation on native tortoises and other reptiles

Country/Region	Invasive Alien Animals	Origin	Impact
United States	Asian carp	Asia	Compete with local fish food resources, causing imbalance in aquatic ecosystems
Australia	European rabbit	Europe	Destruction of vegetation and agriculture, leading to the extinction or endangerment of native species
United Kingdom	Grey squirrel	North America	Competition for habitat and food resources with native red squirrels, leading to a decline in the number of red squirrels
New Zealand	Rat	Worldwide	Prey on eggs and chicks of native birds, causing some bird species to become endangered or extinct
South Africa	Sulphur-crested cockatoo	Australia	Competition with native bird habitats, causing damage to crops
Brazil	American bullfrog	North America	Prey on amphibians and small invertebrates, threatening native biodiversity
Canada	Red imported fire ant	South America	Threat to human health, damage to ecosystems
Spain	Zebra mussel	Black Sea and Caspian Sea regions	Block water supply systems and hydropower facilities, leading to a decline in the number of aquatic life
India	African giant snail	Africa	Destroy crops and spread plant pathogens
Japan	Wild boar	Europe	Destroy farmland and forests, threaten local biodiversity
Argentina	European rabbit	Europe	Destroy agriculture and ecosystems, threaten local species
Hawaii (United States)	Bullfrog	North America	Prey on local amphibians and insects, threatening local ecosystems
Italy	Zebra mussel	Black Sea and Caspian Sea regions	Destroy aquatic ecosystems, clog water pipes, and damage fishery resources
France	Alligator snapping turtle	North America	Prey on fish and amphibians, destroying aquatic ecosystems
China	African giant snail	Africa	Destroy crops, affect local ecosystems and agriculture
Chile	Wild boar	Europe	Destroy forest vegetation and threaten local wildlife
Philippines	Cane toad	Central and South America	Prey on local species, toxicity threatens other animals, and destroys ecosystems
Indonesia	Nile tilapia	Africa	Competition with local fish resources, resulting in a decline in the number of local fish
Singapore	Green iguana	Central and South America	Destroy garden plants and habitats, posing a threat to native species

One of the countries most affected by invasive alien animals is Australia. Australia has a unique ecosystem and isolated geographical location. Having been isolated from foreign species for a long time, native species lack the ability to resist foreign invaders. Here are some of the key invasive alien animals and the measures Australia has taken to control them:

Impacts of invasive alien animals on Australia

European Rabbit

Influence: European rabbits were introduced in the 19th century and have rapidly multiplied, destroying vegetation, causing soil erosion, and threatening the survival of multiple native plant and animal species.

Feral Cats

Influence: Feral Cats Preys on native Australian birds, reptiles and mammals. Their predation has led to a sharp decline in the number of many native species, and even species extinction.

Cane Toad

Impacts: Cane toads were originally introduced to control pests, but they quickly spread and had an impact on local Wildlife poses a huge threat because they are poisonous and animals that prey on them are often poisoned to death.

Red Fox

Impact: Red foxes prey on small native mammals and birds and are one of the main causes of extinction of many native species in Australia.

Feral Camel

Impact: Feral camels disrupt Australia's arid ecosystems, destroying water sources, plants, and even infrastructure.

Control measures taken by Australia

The Australian government and environmental agencies have taken a variety of measures to control the spread and impact of invasive alien animals. These measures include:

Physical capture and eradication

For many invasive species, Australia has adopted direct capture, hunting or trapping to reduce their numbers. For example, the number of feral cats and red foxes is controlled by setting traps and organizing targeted hunting activities.

Biological control

For European rabbits, Australia has successfully introduced viruses such as **MyxomatosisandRabbit Haemorrhagic Disease (RHDV)** to reduce the number of rabbits by spreading diseases. These biological control methods have greatly reduced the size of rabbit populations.

Chemical control

Use targeted poisons and chemicals to control the spread of invasive species. For example, poisons are used to control the red fox population, and chemicals are used to reduce the breeding area of cane toads.

Fences and isolation

Constructing predator-proof fencing is an effective way to protect native species in Australia. These fences can isolate native species from invasive predators and create safe habitats.

Public Education and Community Engagement

Australia actively promotes public education activities to raise people's awareness of alien species and encourage local communities to participate in the management and control of invasive species. Especially in rural and remote areas, the government and non-governmental organizations have carried out workshops and activities to help local residents identify and deal with invasive species.

Legislation and Policy

Australia has a series of biosecurity laws, which strictly restrict the introduction of alien species and impose heavy penalties on violators. For example, Australia prohibits individuals from bringing in alien animals or plants without permission.

Other severely affected countries

In addition to Australia, New Zealand, the United States and South Africa are also countries seriously affected by alien invasive animals. New Zealand's ecosystem is particularly sensitive to invasive species, such as rats and possums, which pose a great threat to its unique bird species. The United States faces challenges from invasive species such as Asian carp and crape myrtle mussels, and the government responds through physical control, biological control and legislation.

Australia is one of the countries most affected by invasive alien animals, and its unique ecosystem faces great challenges. Through a combination of biological control, physical control, chemical means and public education, Australia is actively responding to this global issue. The implementation of these measures has not only helped Australia protect its unique biodiversity, but also provided important reference for other countries to deal with invasive alien species.