Wild rabbits are implicated in the decline of many species of native animals. In the south-east of South Australia, the wombat population declined markedly once rabbits invaded the area. We now know that bilbies usually disappear from an area within 10 years of rabbits arriving. The bilby is now endangered and only found in isolated areas of central Australia where rabbits are absent. Wild rabbits also affect native wildlife by supporting feral predators particularly the European fox.
Problems caused by rabbits often go unrecognised by the untrained eye until it is too late.
Brian Cooke is Australia's leading rabbit ecologist. Rabbit densities of six to seven per hectare are common in arid zones. David Lord, a primary producer in western New South Wales, can trace damage caused by wild rabbits and the enormous effort and cost involved in rabbit control through experience on his property, Thackaringa Station. Rabbit populations of less than three per hectare can maintain the dominance of introduced plants. But when rabbits are excluded, native grasses can replace introduced species.