Question: How did cats get into Australia?
That we humans have a dismal record for exterminating other species is clear, but less well known is the Great Dispersal. We have carted vast numbers of plants and animals around the globe to places they don't belong. It's a long list, including foxes, rats, pigs, prickly pear, and European wasps. These are both facets of the new geological age called the Anthropocene.
Every continent has been affected by introduced species, but few more than Australia. Some are accidental, but some are deliberate. Among them are one of our favourite travel mates, the cat. They're compact, companionable, and they eat vermin. This makes them an ideal passenger on long ship voyages.
Aboard his ship, HMS Reliance Matthew Flinders had a cat named Trim. It won his affection by climbing up a rope after falling overboard. Together they circumnavigated Australia on the HMS Investigator. Later they were shipwrecked when The Porpoise struck Wreck Reef in 1803. Trim's survival skills show how hardy the species is – and give a clue to how cats fared on arrival in Australia.
Cats originated in West Asia, and first became attached to humans in ancient Egypt. A co-burial site has been unearthed suggesting our association may go back to 9500 years ago.
Cats most likely first came to Australia about 200 years ago during European settlement. Genetics research suggests they arrived at coastal sites around 1820. By 1890, they had colonised most of central Australia: just 70 years to establish over an area of 7.6 million square kilometres.
There are now few parts of the continent and surrounding islands from which cats are absent.
Cats are well adapted to the Australian environment. They do not require free water if live prey is available. They are agile, and stalk prey. Where food is plentiful, such as around tips, there can be as many as 700 to 2000 in each square kilometre. Typical densities in natural environments are less than one to each square kilometre, varying greatly in arid environments between boom and bust conditions.
Response by: Rod Taylor, Fuzzy Logic, with thanks to Australian Wildlife Conservancy
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