Struthio camelus
Afrikaans:Volstruis
Zulu: iNtshe
German: Vogelstrauß
French: autruche
Roberts' # : 1
The Ostrich is the largest and strongest of living birds, attaining a height from crown to foot of about 2.4 m (nearly 8 fee) and a weight of between 140 to 230 pounds (63-105kg). They have long necks and small heads, with large eyes and short, broad beaks. They spread their small wings when running and have long, powerful legs that are used for defence. They have evolved a cloven hoof consisting of only two toes, similar to that of the other animals that share its plain's existence.
It is a bird that cannot fly and is a member of the flightless family of birds called ratites. Adults can run faster than some antelope, and month-old chicks have been clocked at 35 miles per hour. The wings are used for a great variety of highly developed displays, but not for flying. Having abandoned flight the ostrich has lost the strong, stiff feathers of the wing and tail that mark aerial species. Instead, a growth of soft plumage, with almost the warmth of down, acts as an insulation against the harsh temperature endured by ostriches throughout their arid range. The ostrich's wings are very small. Two of the wing fingers end in claws or spurs that can be used in attack.
Excellent eyesight and acute hearing are the ostrich's most important senses. The ostrich's thick eyelashes protect its eyes during sand storms.
Ostriches usually travel in small flocks of five or six, but are also seen in groups of up to 50 members. The ostrich is an extremely wary bird – its height and keen sight make it an excellent sentry, and they can rarely be approached within100 yards in the open. Males defend their territories in the breeding season by patrolling, by marking displays to chase out intruders, and by booming. Their call is surprisingly loud and deep, and is accompanied by inflation of the brightly colored neck skin. Their aggressive display consists of repeated flicking of wings, and postures with both wings raised. Breeding males display dramatically to females by squatting and waving their huge spread wings alternately.
Gender differences:
Male ostriches are black, with white wings and tail. The female is a dull grayish brown.
Habitat:
Ostriches can be found in sub-Saharan Africa., for example among the salt bushes that grow on the Southern African savanna. A non-migratory bird, the ostrich frequents sandy wastes, deserts, and some regions with low brush and thorn trees, Ostriches are nomadic, wandering wherever food is most readily available. However, they never stray very far from water, of which they need a gallon-and-a-half a day.
Diet:
Ostriches eat various seeds, berries, wild figs grasses, bushes and forage on trees. They supplement this diet with animal food such as invertebrates and small vertebrates, which they chase by running. The ostrich will, in fact, swallow almost anything – from stones (needed for digestion) to coins and broken glass.
Reproduction:
Ostriches are polygamous. The male gathers around him a harem of three to five females, all of which lay their eggs in the same nest over a three week period. Thus, a clutch of about 25 eggs is laid in the nest which is nothing more than a shallow scrape, which has been made by the male. Ostrich mating and egg laying will occur shortly before the onset of the rainy season, so that when the chicks hatch there will be plenty of food to sustain them until they are several months old.
The eggs are almost spherical in shape, weighing up to 3.3 pounds, with a shell 2-mm thick. It is about 6 inches long and equivalent in volume to about 20 - 24 hens' eggs. Such a clutch laid on open ground presents a significant meal to a jackal, the dominant predator. While defending their nests, ostriches can be very aggressive and have been said to kill young lions with their strong kicks. In fact, kicking is the bird's best weapon and delivers 500 pounds of force per square inch. Only about half of the ostrich eggs that are laid hatch out.
The completed clutch is incubated by the male at night and the dominant female during the day. The reason for this is that at night the dark feathers of the male ostrich makes detection by predators more difficult. Likewise, during the day the female's lighter brown feathers blend in with the surrounding grassland colors. Shortly before the eggs hatch, the chicks will start calling from inside the shell, so the parents
will know them by their calls once they are hatched. The young hatch after 45 days. The chicks run about within minutes of hatching.
The parents keep close watch over the chicks constantly. They will leading them to food (seeds and vegetation),water and they will provide shade for them. Even with the protection of the parents only about 1 chick in 10 will survive its first year of life. The chick becomes independent at the age of 1 year.
Ostriches begin breeding at the age of 4 and their lifespan is between 30 to 70 years.
Other:
The white feathers of the male, which are large and soft, are the ostrich plumes of commercial value.
It is just not true that the ostrich hides its head in the sand in time of danger. But young birds will conceal themselves by lying down and stretching their necks out along the ground.
Mutually beneficial association occurs in the bush environment: four-footed mammals flush food for the ostrich, and in turn depend on the seven foot stretch of the birds’ neck and its keen vision to alert them to danger.
Rock carvings in the Sahara reveal that humans have used the ostrich and its products for at least 10,000 years. Decorated cups made from their strong eggshells have been found in Assyrian tombs dated at 3000 B.C. Ancient Egyptians also used the eggshells for drinking vessels.
The size of the ostrich egg is remarkable in two ways: it is the largest bird egg in the world, yet the smallest in relation to the size of the adult bird.
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