KORI BUSTARD by Doreen Mcolaugh
Our first Bird of the Month, the Ostrich, is the largest and heaviest bird in the world, but it cannot fly while the Kori Bustard is the heaviest bird in the world that can fly. We feature this bird not just for this reason but also because it was designated by government as Botswana’s National Bird in 2014. Although over the years several different birds, and especially the Lilac-breasted Roller, were considered to be the official national bird, none had ever been officially designated as such. The Kori Bustard, Ardeotis kori kori, also stands out for being one of the few birds that takes its English name directly from its Setswana name, Kgori. In Botswana culture this bird has long been considered the Chiefs’ bird (nonyane ya dikgosi) and was not to be hunted or consumed by anyone except a Chief (considered to be of Royalty) or someone to whom he gave permission to do so. People were told that if they went against this rule they would succumb to mental illness and so perhaps this gave some protection to the bird. A culturally respected bird, there are proverbs and traditional stories that feature it.
Bustards occur in other parts of Africa with Kenya possibly having the largest populations. Two separate populations of Kori Bustards exist with the subspecies Ardeotis kori struthiunculus found in Kenya, Tanzania and Ethiopia while Ardeotis kori kori is in Botswana and its neighbouring countries. In Botswana five large and medium-sized bustards have been recorded; Kori Bustard, Denham’s Bustard, Ludwig’s Bustard, Black-bellied Bustard and the White-bellied Bustard. The smaller bustards – called korhaans – that occur here are the Red-crested Korhaan and Northern Black Korhaan. The Kgori and other bustards have been featured in colour on the 2017 Botswana postal stamp series Endangered Birds of Botswana: The Bustards.
All bustards are terrestrial; ground dwellers that do not roost or nest in trees. The Kori male can weigh as much as 20 kg and thus, although it can fly with a wingspan of up to 275 cm, is a reluctant flier that needs open space to be able to get airborne. Once up, it can fly strongly but usually does not fly far before landing and then walking away from perceived danger. Although they are wary birds, researchers have noted that they are fairly easy prey for many predators as diverse as Martial Eagles, lions and humans.
The 135 cm tall male Kori is cryptically coloured to match its habitat in the Kalahari bush and tree savannah that also has open grasslands. Brown on the upperparts and wings that have black markings and a grey looking neck that on closer inspection consists of finely striated black markings covering the upper parts of loosely attached white neck feathers, and white underparts. The Kori Bustard has a dark crest of feathers on the head that can be raised. The much smaller female is similarly coloured. The chicks are a well camouflaged brown. Koris do not have a preen gland that most other birds have to clean and groom their feathers but they do produce powder down that helps keep their feathers clean and they also practice sun bathing and dust bathing.
Both Ostriches and Kori Bustards are sexually dimorphic but in different ways. Male and female Ostriches are the same size but they demonstrate their sexual dimorphism by colour with the male being black and white while the female is brown. The Kori demonstrates sexual dimorphism by size difference between males and females with the male being 25 – 50% larger than the female while their plumage is very similar.
The Kori male uses his size to attract females to his “ lek”. A lek is an assembly area where some animals, including some birds, gather to carry on display and courtship behaviour. The Kori male goes to his lek area and then struts around in his mating finery, making himself to appear as large as possible – the larger he looks the more attractive to the females! He raises his head crest, drops his wings and cocks his tail straight up with the white undertail coverts conspicuously displayed, and then is able to inflate the front part of his neck until it looks like a balloon. The greyish-looking neck feathers that cover the ballooned area of the neck then tip up towards the head showing their very white underside – also very conspicuous. All of this can be seen and his booming mating call heard from a good distance away, attracting females to his lek. He quickly mates with various females in turn that come to his lek, each leaving after she mates. The male’s duties are then finished – he does not pair with any of the females, nor help incubate the eggs nor assist in caring for the young. Should you see two or three or more adult-sized Koris together you are probably seeing a female with almost grown offspring or a temporary gathering of adults at a good food source. Offspring stay with their mothers into their second year. Once mature they leave but do not breed until they are fully mature at 3 – 4 or even 5 years of age. Kori Bustards have been known to live as long as 25 years in captivity but in the wild it is not definitely known what their average lifespan is.
Alone, the female may scratch a shallow nest on the ground or just find a shallow depression – normally near a bush or tree or a big rock that gives some protection and then usually lays two light brown eggs. Being brown on the upperparts she blends in with the habitat during the breeding season that is usually between October and December. She incubates the eggs for 23-25 days – seldom leaving the nest. Once hatched the chicks are precocial and active within hours. They are well camouflaged and they and the nests are difficult to find. The female brings them soft food and by a couple of weeks they are also accompanying her and finding food for themselves. They grow rapidly and fledge at 4 – 5 weeks but are not strong fliers until at 4 -5 months. It is reported that over 80% of Kori Bustard chicks do not survive their first year. In times of drought when little food is available the young normally do not survive at all. Under extreme drought conditions Koris don’t even attempt to breed.
Kori Bustards are omnivores and will eat almost anything including grit and small pebbles that aid in digesting the various foods they consume. They walk along feeding on berries, green grass, bulbs, seeds, melons, a variety of insects from caterpillars to dung beetles, bird eggs and hatchlings, as well as small animals including rodents, lizards and snakes. They even will eat carrion. Koris are very fond of eating gum from Acacia trees, earning them the common Afrikaans name of meaning “gum peacock”. Although adapted to arid areas, Koris also need water if their food doesn’t have enough moisture to sustain them. When drinking the Kori sucks the water up rather than scooping it up with its bill as most birds do. Kori Bustards are often found in company of different antelopes and other large wildlife, feeding on insects and small mammals that those large animals disturb when moving about. In areas where Carmine Bee-eaters are found such as in Chobe National Park the bee-eaters can often be seen perched on Kori Bustards and hawking insects disturbed by the bustards as they move about.
Botswana is considered the stronghold for the species and Kori Bustards are common in the Central Kalahari Game Reserve and other central and northern protected areas such as Chobe National Park, the Tuli Block and the Kalagadi Transfrontier Park but are scarce elsewhere. Numbers of the Kori Bustards have decreased in recent years due to hunting for the pot (Koris are called by some the Christmas Turkey or the Kalahari Kentucky) or for sale of their meat to others especially across the southern border, or sold alive to exotic bird collectors, or sold for their feathers that are used to make fishing flies or lures for fishermen. Apparently Koris are easily snared using Acacia gum as bait to trap them. They are also losing their natural habitats due to overgrazing by livestock which results in too much bush encroachment. Being wary birds that keep their distance from humans, they are disturbed by ever increasing developments. They also are victims of frequent collisions with overhead powerlines. Poisons to control outbreaks of locusts may also affect them. Kori Bustards are now classified as Near Threatened. Hopefully their current status as Botswana’s National Bird will help people to learn more about them, appreciate them and desire a healthy future population of these magnificent birds for future generations to enjoy.
Kori Bustards have become popular additions to zoos in the United States and other countries. The zoos where they are located do a lot of research on these birds and share their information with other zoos and institutions through their Kori Bustard newsletters that you can view online.
The Kori Bustard features in ancient San rock art and still in Botswana today in San/Bushman songs and dances. Many Setswana proverbs and general folklore are said to exist about Kori Bustards, with one example being Kgori e bona mae, lerapo ga ele bone, meaning The Kori sees the eggs but does not see the trap. This suggests that although Koris are alert birds, they can easily be trapped. The following “King of the Birds” story is one that is also known in other cultures.
This interesting traditional story, “King of the Birds”, features the Fish Eagle, Giant Eagle Owl and Kori Bustard as well as the tiny Neddicky bird. The folktale in short is: After the Creator had finished making the beasts of the sea, land and sky, including people, the Fish Eagle called a meeting of all the birds who then gathered from near and far. The Fish Eagle said now the Lion was the King of all Land Beasts but Lion certainly could not speak for birds, the Beasts of the Air. He proposed that they choose a leader. After much discussion the mighty Fish Eagle suggested that he should be the King of the Birds because he was the most majestic and regal bird present. The Giant Eagle Owl stated that he should be king of the winged animals as with his large eyes he sees everything that happens and therefore was very wise. Then the Kori Bustard strode to the front saying as the largest of flying creatures certainly size and strength were necessary for the post of leadership. After a long time of all the birds arguing about who should be king the tiny Neddicky came forward saying he should be the king. All the birds laughed but thought he was courageous.
The birds agreed there should be a competition and that the one that flew the highest and could touch the hand of God would become King of the Birds. As the three large competitors gathered on the day of the competition tiny Neddicky also was there and was able to sneak under the wing of the Fish Eagle where he hid in its feathers. The birds took off and of the Fish Eagle, Giant Eagle Owl and Kori Bustard, Owl was the first of the three to tire and so he landed and then the heavy Bustard tired also, leaving the Fish Eagle still flying higher although he was also tiring. It was at this time that Neddicky untangled himself from Fish Eagle’s wing feathers and then managed to fly higher than the tired Fish Eagle. He then claimed the Kingship but the birds on the ground saw that he had cheated and were ready to pluck out all his feathers so he had to escape to the forest and hide. To this day there still is no King of the Birds. (For the full story that also explains why owls are nocturnal see CanTeach: Africa – King of the Birds (A Traditional Zulu Story) ).
Burton, Robert.1985. Bird Behaviour. Granada Publishing: London, England.
Hancock, Peter and Ingrid Weiersbye. 2016. Birds of Botswana. Princeton University Press. Princeton, New Jersey.
Liversidge, Richard.1991. The Birds Around Us. Fontein Books: Parklands, South Africa.
Tarboton, Warwick. 2001. Nests and Eggs of Southern African Birds. Struik Publishers: Cape Town.
A description of commonly observed behaviors for the kori bustard (Ardeotis kori) by E.M. Lichtenberg and S. Hallager, Smithsonian National Zoological Park, Washington, D.C.
BWgovernment – GOOD NIGHT FROM BOTSWANA - OUR NATIONAL BIRD THE KGORI
CanTeach: Africa – King of the Birds (A Traditional Zulu Story)
THE GOMPOU, The kori bustard SSP newsletter
WIKIPEDIA Kori bustard