Why are numbats only in Western Australia now?

Numbats are in a worse position than being threatened - they are officially endangered.

The primary cause of numbats being restricted to just Western Australia is largely because of the introduction of non-native species to Australia in settled areas of southern Australia. Introduced species such as foxes, and feral cats and dogs, caused the loss of huge numbers of numbats. It is a small, quite defenceless creature, only able to protect itself by hiding in hollow logs.

Another reason is habitat loss. Their habitat has been cleared for industry, agriculture and expanding human habitation throughout their former range of southern Australia.

Bushfires and changed fire regimes have also contributed to the numbats' endangerment. Bushfires destroy the numbats' habitat, including the logs in which it shelters. Numbats are not fast-moving creatures, and they cannot escape bushfires, which can move very quickly.