<P> Cats are kept as pets in Australia and are also one of the major invasive species that are causing detrimental effects to indigenous wildlife . For biosecurity reasons any cats that are imported into Australia must meet conditions set by the Department of Agriculture, Fisheries and Forestry . </P> <P> There are now an estimated 2.7 million domestic cats and over 18 million feral cats in Australia . </P> <P> Historical records date the introduction of cats to Australia at around 1804 and that cats first became feral around Sydney by 1820 . In the early 1900s, concern was expressed at the pervasiveness of the cat problem </P> <P> It has been identified that domesticated cats predate on native animals, and surveys of catches have regularly occurred </P>

When was the feral cat introduced to australia
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