By Keenan Donegan
Geographic Range
Up until the mid 20th century, ostriches occurred naturally in southwestern Asia, the Arabian peninsula, and Africa. They have since been hunted to extinction except in sub-Saharan Africa.
Habitat
Ostriches are currently restricted to drier and sandy regions of central and southern Africa.
Terrestrial Biomes:
savanna or grassland
; scrub forest
.
Physical Description
(198 to 286 lbs)
Unmistakeable. Huge (stands 2 m tall), terrestrial bird. Males are black and white, females gray brown.
Some key physical features:
endothermic
; bilateral symmetry
.
Reproduction
Exact pattern varies geographically. Ostriches form bisexual groups with a complex structure. Territorial males compete for flocks of 3 to 5 hens. Elaborate displays, including hisses and other noises, are often used by males to intimidate each other. Once divided into mating groups, ostriches in some areas use communal nests to hold anywhere from 15 to 60 eggs. The nest is a hole scraped in bare ground. The average egg is 6 inches in length, 5 inches in width, weighs about 3 pounds, and is shiny and whitish in color. Eggs take approximately 40 days to hatch. Caring for their eggs is divided up between males and females. Males watch over them during the night, and the various females of the mating group take turns during the day.
Key reproductive features:
iteroparous
; gonochoric/gonochoristic/dioecious (sexes separate); sexual
; oviparous
.
Behavior
Ostriches live in flocks of 5 to 50, and they are normally found in the company of grazing animals like antelope and zebras. Flocks occupy territories of 2-15 sq km during the breeding season, which lasts around 5 months. Smaller, looser groups of 2-5 members are formed outside of the breeding season.
Another characteristic of ostriches is that they are very fond of water. They frequently take baths when given the opportunity.
Sometimes, in order to escape detection, ostriches may lie on the ground with their necks outstretched. This peculiar behavior probably gave rise to the myth that ostriches bury their heads in the ground.
Key behaviors:
terricolous; diurnal
; motile
; nomadic
; territorial
; social
; dominance hierarchies
.
Food Habits
Ostriches are herbivorous living mostly on plant matter, but they occasionally eat animal remains left by carnivorous predators. They are very selective feeders, taking the seed heads of grasses and certain flowers and seeds. They sometimes eat locusts. An ostrich in captivity requires 3.5 kg of food per day. They can survive without water for long periods of time.
Animal Foods:
carrion
; insects.
Plant Foods:
leaves; seeds, grains, and nuts; fruit.
Economic Importance for Humans: Positive
Ostriches were often killed for the use of their hides, which makes a fine leather, and their feathers. Their eggs, which are equivalent to 24 fowl eggs, are eaten by animals as well as humans. African tribes use ostrich shells as a means of holding water for bathing and drinking.
Conservation Status
Ostriches were almost wiped out in the 18th century due to hunting for feathers. By the middle of the 19th century, the practice of farming ostriches began to spread. This enabled ostriches to be domesticated and plucked, instead of being hunted and killed. Currently, the demand for ostrich feathers has lessened greatly, and ostriches seem to have a secure population.
Other Comments
Ostriches are the largest living birds. Ostriches do well in captivity and may live up to 50 years both in and out of the wild. Their powerful legs are their main defense against natural enemies. They can achieve speeds of up to 40 miles per hour, and if cornered they can deliver a powerful blow with their legs.
Contributors
Keenan Donegan (author), University of Michigan.

