After the extinction of the elephant birds of Madagascar and the giant moas of New Zealand less than 1,000 years ago, the common ostrich (Struthio camelus) is now the world’s largest extant species of bird. Found across the savannas and semi-deserts of Africa, this huge ratite also lays the largest eggs of any living bird. The common ostrich is one of two species of ostrich, the other being the Somali ostrich.
Males of this species can reach a mighty 9 feet in height and weigh as much as two adult humans. Despite its size, the ostrich can hit speeds of over 40 mph – the fastest land speed of any bird. It’s clear to see that this hefty flightless bird is not lacking in world records. Ostriches exhibit sexual dimorphism; the males have a bold, black plumage whilst females have a greyish-brown plumage. Both sexes have an almost bare head and neck. It is thought that these ostriches have the largest eyes of any land vertebrate – around two inches in diameter. Their beady eyes help them to see predators from a distance.
For me, the most impressive aspect of the ostrich is their prehistoric, two-toed feet. Each toe has a long, sharp claw resembling that of a velociraptor. These feet can be powerful weapons. A kick from an adult ostrich can kill a human or a potential predator such as a lion. Most birds have four toes on each foot but the ostrich’s two-toed feet assist in running.
Ostriches mainly feed on grasses, seeds, shrubs, fruits and flowers but will also eat insects and lizards when available. Their large size and seemingly vulnerable build makes them a tasty target for a whole host of predators. Lions, cheetahs, leopards, painted wolves and spotted hyenas just to name a few. The nests where they lay their large eggs attract smaller predators in the food chain such as jackals, mongooses and vultures.
Female ostriches will lay their eggs in a communal nest. The dominant female will lay 7-10 eggs in the centre of the nest and the other females lay their eggs around them. These nests can hold up to 60 eggs. This seems like a lot of eggs, but it is thought that fewer than 10% of nests survive the 9 week incubation period, and of the surviving chicks, only 15% make it through their first year.
Ostriches have developed an ingenious method of incubation to avoid predators. During the day, females will incubate the eggs because their dusty colouration blends in with the sand. However, during the night, males will takeover because their coal-coloured feathers make them almost indistinguishable at night. Ostrich chicks are cute and cuddly in appearance. They are cream in colour with a charming pattern of dark spots along their head and neck.
Although ostriches occupy a vast range their numbers are declining, largely due to habitat loss. I am hopeful that the ostrich will live on for centuries to come and we won’t have repeat the history of the elephants birds of Madagascar and the giant moas of New Zealand. Today, we are knowledgeable enough to understand the consequences of our actions and we are the only ones able to control those actions.
Hennessy, K., Wiggins, V. (2014) Animal Encyclopedia: The Definitive Visual Guide. 2nd edn. London. Dorling Kindersley.