Birds: Emu

Range: Australia Habitat: grassy plains and open forests

Primordial birds

Tall and majestic, the emu belongs to a group of flightless running birds known as ratites, the most primitive of the modern bird families. The ratite family includes the kiwi, ostrich, cassowary, and rhea, all birds found only in the Southern Hemisphere. The soft-feathered, brownish emu is common throughout most of mainland Australia, although it avoids big cities, dense forests, and deserts. The emu is the second-largest living bird in the world (the ostrich is the largest), with adult female emus being larger and heavier than the males.

Horse feathers!

Individual emu feathers have a very loose and simple design. Just like hairs, feathers grow from follicles. Typically, birds have one feather per follicle, but the emu grows a double-shafted feather from each follicle. The closely-knit barbs found on a typical feather are widely spaced on the emu feather and don't have the usual hooks that attach to the other barbs. Instead, each barb hangs loosely and gives emu feathers a hairlike appearance. Other ratites share this feathery design. When new feathers grow, they are almost black in color, but the sun soons fades them to a grayish brown while the shafts and the tips of the feathers remain black. Emu feathers are less water-resistant than other birds' feathers.

An emu's tail feathers are not so soft. Instead, they are stiff and can be rattled by the bird to scare off predators, such as dingoes.

Born to run

Emus have tiny, relatively useless wings, but their legs are long and very powerful. They can travel long distances at a fast trot and can sprint at 30 miles per hour (48 kilometers per hour) for quite a distance. Emus are the only birds with calf muscles. Their feet have three toes and fewer bones and muscles than those of flying birds. Their strong legs also allow the bird to jump 7 feet (2.1 meters) straight up. With good eyesight and amazing agility, emus can escape most any trouble!

You headin’ my way?

Usually solitary, emus can form enormous migratory flocks when moving toward better food resources. Flocks have been tracked traveling long distances for food. In fact, in Western Australia, emu movements follow a seasonal pattern: northward in the summer and southward in the winter.

Seasonal taste treats

Emus are ominivores and typically look for food during the day. They eat a variety of plants, depending on the season. For example, they will eat Acacia seeds until the rains come, afterward eating new grass shoots and caterpillars. In wintertime, they feed on the leaves and pods of Cassia. Springtime brings beetles, grasshoppers, and fruit. They also eat crickets, ladybugs, lizards, moth larvae, and ants. The San Diego Zoo’s emu eats romaine lettuce, ratite pellets, fruit, and hard-boiled eggs.

The emu serves a very important role in its habitat: seed dispersal specialist! Seeds that are eaten whole often come out whole, and as the emu wanders about, it leaves perfectly fertilized seed-carrying deposits behind in its droppings.

I’ll sing a song for you

The emu has a pouch in its throat that is part of the bird's windpipe and is used for communication. When the pouch is inflated, the emu can make deep booming, drumming, and grunting sounds. These calls are usually made during courtship and the breeding season and can be heard up to 1.2 miles (2 kilometers) away! A hiss, described by one of our animal trainers as "bloodcurdling," is very effective at warning off dingoes.

Stay-at-home dads

Emus form breeding pairs in the summer and typically stay together through the fall, when the first clutch of eggs is laid. The male builds a rough nest of twigs, leaves, and grass on the ground where the female lays 5 to 15 eggs over the span of several days. Once the female is done, she wanders off, leaving the male to incubate the eggs. It's a good thing he ate extra food to build up his reserves of body fat before the breeding season, because he stays on the nest for the next eight weeks, getting up only to turn the eggs, and will lose up to one-third of his body weight. Females may or may not find another male to mate with during this time. This second male may incubate his own clutch, or the female might find the nest of another emu pair where she can lay her eggs. In a good season, a female emu may lay three complete clutches!

Sunny-side up!

Emus are part of the story the Yuwaalaraay people of Australia tell about the sun's creation: A large emu egg was tossed up into the sky. . .. Emu eggs are indeed large, but they’re not sunshine yellow. One emu egg has the same weight and volume as 10 to 12 chicken eggs! The eggs are dark teal green and shiny, with small pits on the surface.

The brown-and-cream-striped chicks are precocial and can leave the nest at about three days old, but they usually stay with their father for nearly 18 months. The father teaches his offspring how to find food and stay safe from dingoes and foxes. Emus are full-grown at 12 to 14 months but don’t reach sexual maturity until about 2 years of age.

Human impact?

The emu subspecies that inhabited Tasmania became extinct around 1865, following the arrival of Europeans. The mainland subspecies’ distribution has also been affected by human activities. Once quite common on Australia's east coast, rapid human population growth forced the emu out of this area. However, agricultural development and water provided for livestock in Australia’s Outback have given the emu new regions to live in that were once too dry for its survival.

While the emu population is currently considered stable, drought and wildfires are potential threats that could easily impact them. Many people raise emus for their meat, oil, and leather.