Emus are the largest native bird of Australia and are the second largest living bird after the ostrich. They stand at 1.5 - 1.9 m (5 - 6.25 ft) in height and they weigh between 30 and 60 kgs (66 - 130 lbs).
They are flightless birds and they have long, powerful legs, three toes on their feet and small wings. Their feathers are shaggy and drooping and they are grey/brown in colour on their body and have a blue/black colouration on their head and neck.
Their calls consist of loud booming, drumming and grunting sounds. The booming sound is created using their inflatable neck sac and they can be heard 2 kms (1.2 miles) away.
Emus are fast runners and they can reach speeds up to 48 km/hr (30 mph). They are also able to swim if required.
Emus live in a variety of habitats throughout Australia. They are most common in areas of sclerophyll forest and open woodland and are least common in very arid areas.
They are either solitary or form loose flocks that can contain dozens of birds.
Emus mainly feed on seeds, berries, shoots and insects. They remain resident in an area if their food supply is plentiful but they are prepared to travel great distances if resources are scarce.
Emus form breeding pairs during December and January but the pair remain together for approximately 5 months before any eggs are laid in May or June. During this period the pair will defend a range of approximately 30 sq. kms (11.6 sq. miles).
The male will construct a nest on the ground made from grass and other vegetation. The nest is 1 - 2 m (3.3 - 6.6 ft) in diameter and approximately 10 cms (4 inches) deep. The female will lay 5 - 15 eggs at 2 - 4 day intervals and the eggs are dark green in colour. The eggs measure approximately 13 x 9 cms (5.1 x 3.5 inches) and they are around 700 - 900 g (24.7 - 31.7 oz) in weight. After the female has finished laying her eggs she usually leaves, and plays no part in the incubation or raising of the chicks. Occasionally a female will stay and defend the nest until the chicks hatch then the male will chase her away.
Despite the initial pair bond, when the male starts incubating the eggs the female will mate with other males, so the eggs that he is incubating are likely to be fathered by several different males. In some instances the eggs may belong to neither parent as Emus exhibit brood parasitism, which is where an individual will use a host to raise their young.
The eggs are incubated for approximately 55 days and during this time the male doesn't leave the nest to eat, drink, or defecate.He only stands up to turn the eggs over which he does around 10 times per day. Upon hatching the chicks weigh 440 - 500 g (15.5 - 17.6 oz) and they have cream and brown stripes to help them stay hidden.
The chicks leave the nest between 2 and 7 days but they stay close to the male for 5 - 7 months. During this time their stripes fade and their plumage is replaced by brown feathers. Emus are fully grown at 12 - 14 months old and they become sexually mature at 2 - 3 years of age.