The southern boobook is the smallest and most common owl in Australia. It is identified by its plumage, which is dark chocolate-brown above and rufous-brown below, heavily streaked and spotted with white. The bill is grey with a darker tip, and the feet are grey or yellow. The facial disc is chocolate brown and the eyes are large and yellowish. Tasmanian birds are smaller and more heavily spotted with white, while birds of the Cape York rainforests are slightly larger and darker. Young southern boobooks are almost entirely buff-white below, with conspicuous dark brown facial discs. Like other owl species, the southern boobook is nocturnal. Birds are often observed perched on an open branch or tree-top. It is also known as the 'Mopoke'.