You’ve probably heard some of the hubbub surrounding feral cats in Australia, and more specifically what to do about them. The feral cats (domestic cats that live independently from humans) are considered an invasive species there and are said to pose a threat to native populations of birds and small mammals. Earlier this year, the government announced a plan to eliminate (i.e., kill) as many as 20 million of these cats in the next five years. But where did these cats come from originally, and when did they arrive? The answer to that second question in particular can “provide an important timeframe for the impact of feral cats on native species in Australia,” according to a study published today in BMC Evolutionary Biology.
The exact origins of the Australian cats hasn’t really been known before now: different theories have claimed they could have come on the ships of Europeans in the late 1700s, or with Malaysian trepangers (people fishing for sea cucumbers) in the mid-1600s, or even at the same time as the dingo, around 4,500 years ago. The new study analyzed genetic information from over 250 cats from the Australian mainland, several islands, Southeast Asia, and Europe to determine where the cats likely originated. The results: Australian feral cats are descendants of cats that arrived on European ships in the 1800s.
That finding supports the theory that feral cats in Australia originated in “Britain and other Western and Central European locations” and that there were many arrivals of cats in coastal areas throughout the nineteenth century. No evidence was found of cats being brought by Malaysian trepangers, although some cats from Asia may have arrived after the European cats.
This study is interesting to many because its conclusions can be used to show the effects of feral cats on native wildlife, but it is interesting to us because it further shows how humans tend to take cats with them wherever they go. Expect to read more about this in future posts!
Koch et al., 2015, “A Voyage to Terra Australis: Human-Mediated Dispersal of Cats,” BMC Evolutionary Biology.