A brown thornbill in the wild. Photo: supplied

A brown thornbill in the wild. Photo: supplied

All the cunning of a small bird

The crafty ability of one of Australia's smallest birds has baffled ANU researchers.

It seems the tiny brown thornbill, which can grow to a maximum of 10 centimetres long, protects its nest from predators by crying wolf and mimicking the warning calls of other birds, including hawks.

Researchers from the ANU Research School of Biology found the birds use this to scare off predators such as the pied currawong, which can grow to 40 times the thornbill's size. 

"It's not superbly accurate mimicry, but it's enough to fool the predator," said Dr Branislav Igic, who carried out the study during his PhD at ANU.

"A physical attack on a currawong would be no good. They are 40 times the size of a thornbill and will eat adults as well as nestlings."

Find out how Igic and other researchers stumbled across the thornbill's deceit in the video below.