Emu vs Ostrich: What’s the Difference?
The main difference between emus and ostriches is that the ostrich is a two-toed African bird and the largest living bird, while the emu is an Australian bird with three toes and is much smaller. Male ostriches are black and white with bare necks and legs. Emus of both sexes are shaggy gray-brown all over.
| Emu | Common Ostrich | |
|---|---|---|
| Scientific name | Dromaius novaehollandiae | Struthio camelus |
| Lifespan | 10–20 years in the wild | 30–40 years in the wild |
| Weight | 30–55 kg (66–121 lb) | 90–145 kg (200–320 lb) |
| Size | 1.5–1.9 m (4.9–6.2 ft) (height) | 1.7–2.7 m (5.6–8.9 ft) (height) |
| Top speed | 48 km/h (30 mph) | 70 km/h (43 mph) |
| Gestation / incubation | about 56 days (8 weeks) | about 42 days |
| Diet | Omnivore | Omnivore |
| Family | Casuariidae | Struthionidae |
| Habitat | Savanna woodland, Eucalyptus forest, Grassland, Scrub and heath, Semi-desert | Savanna, Semi-desert, Dry grassland, Open scrub, Desert plains |
| IUCN status | Least Concern | Least Concern |
Figures shown are for the emu (Dromaius novaehollandiae) and the common ostrich (Struthio camelus).
Key differences
Size
The ostrich is the tallest and heaviest bird alive, standing well above a tall person and weighing roughly three times as much as an emu. The emu is the second-tallest bird in the world, although the cassowary is heavier. Side by side, an ostrich looms over an emu, with a much longer neck and legs.
Toes
The ostrich is the only bird with just two toes on each foot. The large inner toe bears a thick, hoof-like nail, an adaptation for running that reduces contact with the ground. Emus have three forward-pointing toes, like cassowaries and rheas. The footprints are unmistakable where the birds walk on sand or mud.
Plumage
Adult male ostriches have black body feathers with white wing and tail plumes, while females and young birds are gray-brown. Their necks and thighs are nearly bare. Male and female emus look alike, in loose, shaggy, hair-like plumage. Each emu feather has two shafts growing from one base, and the neck shows patches of bluish skin.
Wings
Neither bird can fly, but their wings differ greatly. Ostrich wings are large and are used in courtship displays, to shade chicks and for balance when the bird turns at speed. Emu wings are tiny, hidden beneath the body feathers, and each ends in a small claw.
Eggs and parenting
Ostrich eggs are glossy cream-white and are the largest eggs of any living bird. Several hens lay in one communal nest, and the main hen incubates by day and the male by night. Emu eggs are dark green. The male alone incubates them, barely eating or drinking until they hatch, then raises the chicks.
Range
Wild ostriches live in the savannas, deserts and open woodlands of Africa, and the Somali ostrich of the Horn of Africa is now considered a separate species. Emus are found only in Australia, across most of the mainland, from coastal woodland to arid interior. Both are farmed around the world for meat, leather, oil and feathers.
How to tell them apart
- Count the toes: two mean ostrich, and three mean emu.
- A black-and-white body with a long, bare, pinkish or grayish neck is a male ostrich.
- Shaggy gray-brown plumage over the whole body and a bluish neck identify an emu.
- Large wings fanned out in display belong to an ostrich. Emu wings are too small to see.
- A huge cream-colored egg is an ostrich's, while a dark green egg is an emu's.
What they have in common
Emus and ostriches are ratites, an ancient group of flightless birds that also includes rheas, cassowaries and kiwis. Both have a flat breastbone without the keel that anchors flight muscles, long powerful legs, and loose, fluffy feathers that lack the interlocking barbs of flying birds. Both are fast runners and omnivores that swallow pebbles to grind food. Both are listed as Least Concern.
Frequently asked questions
Are emus and ostriches related?
Yes, distantly. Both are ratites, but they sit on different branches of that group. The emu's closest relatives are the cassowaries of Australia and New Guinea, while the ostrich lineage split off earlier. Genetic studies suggest that ratites lost the ability to fly several times independently.
Which is faster, an emu or an ostrich?
The ostrich is faster. It is the fastest bird on land and the fastest animal on two legs, able to sustain high speeds over long distances. Emus are also excellent runners, just not quite in the same class. The comparison table above gives the top speeds for both.
Can emus and ostriches interbreed?
No. Emus and ostriches belong to different orders of birds, separated by tens of millions of years of evolution on different continents, and they cannot hybridize. They also differ in size, courtship displays and breeding systems, so they do not attempt to mate even when farmed side by side.
Are ostriches or emus dangerous?
Both can be. An ostrich can deliver a powerful forward kick, and its large clawed toe can cause serious injury, so farmed and wild males are treated with respect in the breeding season. Emus are generally less aggressive but can also kick and scratch hard if cornered.