a family of birds of the order Casuariiformes. These large, flightless birds measure 1.5–1.8 m in height and weigh 45–54 kg. The skeletal structure of the wing is underdeveloped; there are no true remiges or rectrices. The legs are strong and tridactylous. The birds run at speeds of up to 45 km/hr and are also capable of swimming. The plumage is coarse and hairlike, and the feathers have a double shaft. Males and females are similar in coloring (black-brown on top, lighter below) but may be distinguished by their cry.
The single species, the emu (Dromiceius novaehollandiae), is distributed across Australia, except the forested northeast, and on the island of Tasmania. Emus are settled birds, often dwelling in flocks; they inhabit arid plains. They nest in autumn in a pit under a shrub. The seven to 12 dark green eggs are incubated by the male for 58–61 days. Both parents care for the young.
Emus feed on fruits and insects. In some areas they damage fences and trample wheat plantings. In 1932 troops were enlisted to destroy emus in western Australia. Between 1945 and 1960, 285,000 licenses were issued for shooting the birds as agricultural pests.