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emues are the only existing species of it’s genus, Dromaius. The emu is the largest native Australian bird.
Emues are the only existing species of it’s genus, Dromaius. They are the largest native Australian bird.
The largest Australian native bird is the emu. They are also the only existing species of its genus, Dromaius. The scientific name of this bird is Dromaius novaehollandiae. It is the second largest bird in the world (by height), after the ostrich, which is a relative. They reache up to two meters, or six feet, in height and is a brown, soft-feathered, flightless bird. Their weight can be anywhere from sixty-six to one hundred pounds. Their legs and neck are very long (this shows the relation to the ostrich), and they are equipped with small vestigial wings. The emu's call consists of loud grunting, drumming, and booming sounds. These noises can be heard from up to two kilometers (over one mile) away. They tend to avoid heavily populated areas, dry areas, and dense forests. It is found mostly in mainland Australia. These birds can travel great distances at a quick, economical trot and, when necessary, they can also sprint at speeds up to around thirty miles per hour for an extended period of time. This is due to their highly developed pelvic limbs. Their pelvic limb muscles contribute about as much to their total body mass as wings do for flying birds. One reason they may travel significant distances is to find food, as they are nomadic creatures. They generally feed on a variety of insects and plants. They are a a three-toed bird, and they are the only bird with gastrocnemius muscles in the backs of their lower legs. Their eyes are golden brown to black, their feathers can range from brown to grayish brown, and the tips of their feathers are black. The tips also absorb solar radiation, and the inner plumage of the bird insulates its skin. The resulting heat is kept from reaching the skin by the coat’s insulation. This allows them to keep active during the hotter hours of the day. One very unique aspect of the emu’s feather is its double rachis, which emerges from a single shaft. Also, on days those are very hot, this bird pants to maintain its body temperature. The emu’s lungs work as evaporative coolers. For many species of animals, this can cause alkalosis because of the resulting low blood level of carbon dioxide. This does not occur in the case of the emu. They also have very big multi-folded nasal passages which they use in cooler weather, when they are able to breathe normally.
As previously stated, they eat a wide variety of plants and insects. What plants they eat generally, just depends what season it is, and what is available in that season. The insects they consume include ladybirds, grasshoppers, caterpillars, and crickets. They also sometimes eat larvae and even ants. It has been observed that their diets usually change with the seasons. Generally, in the winter, they eat the leaves and pods of Cassia plants. In the spring, they usually eat grasshoppers and fruit. During the months of December and January, they form breeding pairs that will remain together for approximately five months. The actual mating generally occurs in May and June. Male emues go through hormonal changes during the breeding season. These changes include an increase in their testosterone level, Latinizing hormone level, and their testicles grow to double their regular size. They can also lose their appetite.
The female may nest up to three different times in one good breeding season; some females stay with their first nest until the chicks hatch, but most will leave to make other nests. Females lay anywhere from eleven to twenty eggs, which are large, thick-shelled, and dark green in color. Incubation of the chicks takes fifty-six days. The chicks are very active when they are young, and are able to leave the nest after only a few short days. They have brown and cream stripes when they are first born (for camouflage), but these fade away after a few months. The chicks are full grown in about twelve to fourteen months. The population on mainland Australia is generally thought to be higher than it was before European settlement. However, some populations are at risk of extinction due to being very small in number. Some reasons that these populations are now at risk are the clearance and fragmentation of their habitat, predation of young by foxes, deliberate slaughter, domestic dogs, and pigs. Currently, the New South Wales North Coast Bioregion the emu population is listed as endangered by the New South Wales government
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