Of the 21 completely extinct marsupials and rodents in Australia, the red fox and cat have most probably contributed to the extinction of all but two.

Foxes and cats are also blamed for the loss from the mainland of another nine species that survive on islands, sometimes precariously.

Rabbits have been ranked with foxes and cats as among Australia’s worst pests, wild pigs have become major agricultural and environmental problems, cattle in the Kimberley region damage scarce rainforest tracts, and deer escaping from poorly-managed or failed deer farms are out of control in Queensland, Victoria and NSW.