Invasive species

An invasive species is a species occurring, as a result of human activities, beyond its accepted normal distribution and which threatens valued environmental, agricultural or other social resources by the damage it causes. Invasive species have a major impact on Australia's environment, threatening our unique biodiversity and reducing overall species abundance and diversity.
Invasive species include:

• diseases, fungi and parasites
  Invasive diseases, fungi and parasites in Australia affect many native plants and animals and agricultural crops. Quite often when plants and animals have come into contact with introduced diseases, fungi or parasites they do not respond well to treatment. Vaccines are often very expensive to produce and are not feasible to apply broadly to wild animals. Some diseases have contributed to significant losses of species leading to some species becoming threatened or extinct.
  Some of the diseases, fungi and parasites currently of concern because of their impact on native species include: Chytrid amphibian fungus – Chytridiomycosis, Mundulla Yellows, Myrtle Rust (Puccinia psidii), Phytophthora cinnamomi disease, Psittacine beak and feather disease (psittacine circoviral diseas
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  Cockatoo infected by
  psittacine circoviral disease
  Photo: Murdoch University

  
  
• feral animalsIntroduced insects and other invertebrates that are currently in Australia, and which can have a detrimental impact on the environment, include: Invasive bees, Tramp ants
  
• insects and other invertebrates 
• introduced marine pests 
• Introduced marine pests are species moved to an area outside their natural range, generally by human activities, and that threaten the environment, human health or economic values. Marine pests are introduced to Australian waters and translocated inside our waters by a variety of means; including ballast water discharged by commercial shipping, bio-fouling on hulls and inside internal seawater pipes of commercial and recreational vessels, aquaculture operations (accidentally and intentionally), aquarium imports, as well as marine debris and ocean currents.
• weeds  Invasive weeds are among the most serious threats to Australia's natural environment and primary production industries. They displace native species, contribute significantly to land degradation, and reduce farm and forest productivity. Australia spends considerable time and money each year in combating weed problems and protecting ecosystems and primary production on private and public land.