Bird Of The Month; by Doreen McColaugh

Common Ostrich

Ntshe, Ntshwe, Mpshe, Mmampshe, Mmantshwe and Mmantshwe in Setswana                                   

The Common Ostrich, Struthio camelus, is one bird that everyone knows – or think they know. Because the ostrich is different and still retains aspects of its more primitive ancestors it is often the first bird to be featured in a bird field guide. There is a lot of interesting information to consider and appreciate when you view this bird - the largest and heaviest living bird in the world today reaching up to 2.5 m in height and 145 kg in weight! Although that tall and that heavy, it is not the biggest bird that ever lived. The now extinct Elephant Bird of Madagascar and the giant Moa of New Zealand were even larger and laid larger eggs too. Even the scientific name is interesting as Struthio means ostrich but camelus means camelOf course the ostrich is not related to, nor looks like a camel but camelus was included in the name to designate its preferred habitat that is the same camels prefer – dry, open plains. There ostriches can often go for long periods without access to water like a camel – if their food contains enough moisture, although they drink regularly if water is readily available.  Being flightless, the ostrich is grouped with other flightless birds as a ratite. Ratites have a different shaped sternum (breastbone) that does not have a keel (the protruding bone where the strong muscles that go to the wings attach) that flying birds have. Even if they had a keel and strong muscles they are just too heavy to fly. Botswana’s national bird the Kori Bustard is the heaviest bird in the world that can fly, with which you can compare sizes. Ostriches in the wild are now found only in Sub-Saharan Africa as the large number of Asian species of ostriches, reaching as far as China, are now all extinct and even those of northern Africa are all locally extinct.

Male ostriches have mostly black plumage but with some white on the wings and tail. The tail may be buff in colour or with a reddish colour, along with the same colour on their bill and lower legs when breeding. The female is a greyish brown and immatures are coloured like the females until about one year when they get their full adult plumage. The head and long neck are covered with greyish down while the large thighs are bare. The ostrich’s attractive head and bill are rather small for the size of the bird but there is room for their very large brown eyes with thick, long eyelashes over them. Newly hatched chicks have a strange, prickly down that matches their surroundings thus giving them some camouflage. The plumage colours of the male and female help them protect their nest when they take turns incubating the eggs as the female has the day duties and the male takes over at night when it is dark. When on the nest ostriches tend to lay their long necks out in front of them on the ground thus appearing like a mound of something else in the landscape. And NO, ostriches do not bury their heads in the sand!

Ostriches become sexually mature when they are 2 to 4 years old, with the females maturing about 6 months before males do. They will have many opportunities to breed during their lifetimes of 40 - 45 years in the wild and one ostrich lived to 62+ years in captivity!  The breeding season for ostriches in Botswana is August – December. Male ostriches also dance during the breeding season to attract females. Males do a fast step around females while alternately shaking their wings and tail feathers until the female accepts the male’s advances and then she holds her wings down low and runs circles around him. They then mate and unlike other birds the male ostrich has a retractable copulatory organ.  Although ostriches may be seen alone or in pairs they are often part of larger groups where there is a dominant pair. The nest is a scrape in the ground made by the male into which the eggs are laid. The dominant female lays her clutch of 8 - 10 eggs first and then several other females the male has enticed and mated with, lay their eggs in the same nest, however only the dominant pair incubates the eggs. There can be up to 40 or more eggs in the 2 – 3 m wide nest.

The dominant female keeps her eggs – she can distinguish her own – in the middle of the nest and the subordinate females’ eggs in the nest she keeps around the outside. Perhaps if a predator gets an egg it will be one laid by others rather than by the dominant female.  An ostrich egg is huge – the largest in the world - weighing almost 1.5 kg and said to have the volume of about 2 dozen chicken eggs. However, it is actually a small egg when compared to the ostrich’s body size. (The small New Zealand Kiwi ’s egg takes the prize as its egg is equal to 15 to 20 percent of the female’s body size!) Incubation of the ostrich eggs takes about 6 weeks and the chicks when they hatch are about the size of a chicken.  Once hatched it is the male that usually teaches them to feed and fiercely protects them. Ostriches are mainly herbivores eating seeds, roots, berries and grass but they will eat whatever is available and so also eat insects, lizards, snakes and rodents. In order to prepare their food for digestion they also swallow sand and pebbles that help them grind up their food in their gizzard. Like all ratites the ostrich does not have a crop to store food in as other birds do and you can see a bolus mass of vegetation or other food item travel down an ostrich’s long neck to its stomach – well first to the gizzard and then to the rest of the stomach. Also different from other birds the ostrich has special excretory organs where the urine and faeces are stored separately.

You often will see a dominant pair with up to 40 or so young of different sizes. This is not that some grow a lot faster than others but because there can be a real age difference between the chicks as the dominant pair take/steal chicks from subordinate pairs and raise them with their own.  Why they take on so many to raise is questionable at it is reported that only about 15 percent of all chicks hatched ever reach one year of age. Predators of ostrich eggs and young include jackals, warthogs and mongoose as well as Egyptian Vultures and some birds of prey. Brown Hyenas are known to eat ostrich eggs. Ostriches of all sizes maybe be preyed upon by big cats such as cheetah, lion and leopard while African wild dogs and spotted hyenas also do so.  Ostriches will fight predators to save their chicks. With their long legs and two-toed foot with the main toe having a long, strong nail they strike forward and can kill a predator. Adult ostriches can run at high speeds of up to 70 km/hour over short distances and 55 km/hour over long distances. It can outrun most of its predators, except the cheetah over short distances.

Over time ostriches have been prized for their eggs, eggshells, meat, leather made from their skin, and their beautiful soft and fluffy feathers. This has led to them being farmed since the 19th  century after they were almost decimated in the wild. On some farms today ostriches are also used for entertainment such as racing them, with their human jockeys on board.

Ostriches are said to not have played a major part in religions, myths or folklore but in the ancient rock engravings in the Karoo the ostrich is often among the most depicted -  eland, elephant and rhino. There are wonderful San stories such as the Race between ostrich and tortoise, How man/the trickster stole fire from under the ostrich’s wing where it had always been kept and then learned to cook with it, How a feather became an ostrich, Breach of Peace – why ostriches are afraid of people, among many others. Other tribes had ostrich stories too, such as How the ostrich got its long neck (It wasn’t pulled like in the story of how the elephant got its long trunk).  

The How the Ostrich Got His Long Neck story in summary is: Originally the ostrich had a short neck like most birds.  A male had a flighty wife that was incubating their eggs and one evening he decided to give her a break and said that he would sit on the eggs so she could go find some food. He settled down on the nest for the night but soon was hearing his wife flirting with another male. He then stretched his neck so he could see over the tall grass as to what was going on.  The flirting went on most of the night and since he didn’t want the eggs to be exposed he sat tight on the nest but kept stretching his neck to check on what they were doing.  After all the stretching, the next morning he found himself with a very long neck – and ostriches have had a long neck since that time. The full story can be accessed at https://www.victoriafalls-guide.net.html.

Hopefully, the next time you see an ostrich when you are out birding you will look at it with new interest.

References consulted

Burton, Robert. 1985. Bird Behaviour. Granada Publishing: London, England.

Fourie, Coral. 2000. Splinters from the fire. Protea Book House: Pretoria, South Africa.

Guenter, Mathias. 1999. Tricksters & Trancers. Indiana University Press: Bloomington & Indianapolis, Indiana.

Hancock, Peter and Ingrid Weiersbye. 2016. Birds of Botswana. Princeton University: Princeton, New Jersey.

Liversidge, Richard. 1991. Fontein Books: Parklands, South Africa.

Parkington,John, David Morris, Neil Raush. 2008. Karoo rock engravings. Neil Raush: Southern Cross Ventures: Cape Town, South Africa

Tarboton, Warwick. 2001. Nests and Eggs of Southern African Birds. Struik Publishers: Cape Town.

Common ostrich

 https://en.wikipedia.org/wiki/Common_ostrich 24/9/2018 accessed

How Many Eggs Does A Bird Lay? The Cornell Lab of Ornithology

https://www.allaboutbirds.org

How the Ostrich Got His Long Neck

https://www.victoriafalls-guide.net/ostrich.html 24/9/2018 accessed

Man/ostrich interactions: a cultural History 

https://www.tandfonline.com/doi/abs/10.1080/00359199509520346?journalCode=ttrs20 24/9/2018 accessed

Ostrich

 https://www.britannica.com/animal/ostrich 24/9/2018 accessed

Ostrich Struthio camelus https://animalfactguide.com/animal-facts/ostrich/ 7/9/2018 accessed

Ratite 

www.newworld encylopedia.org/entry/Ratite 7/9/2018 accessed

Struthio camelus australis https://www.google.co.bw/search 7/9/2018 accessed

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