This trumpeter hornbill (Bycanistes bucinator) is sitting on a rock in front of Victoria Falls, or Mosi-oa-Tunya (’The Smoke that Thunders’), Zambezi River, Zimbabwe. These birds are called hornbills because of the strange protuberance, or casque, on their bill. (Photo copyright © by Kaj Halberg)
Hornbills, of the family Bucerotidae, are found in tropical Asia and Africa, comprising 55-59 species. The scientific family name, and the name of the type genus, Buceros, means ‘cow horn’ in the Greek, referring to a peculiar protuberance, or casque, on the bill of most species. Hornbills are very noisy, and the casque is probably a means to increase the volume of their call, which carries quite a distance.
Hornbills vary greatly in size, from the small West African black dwarf hornbill (Horizocerus hartlaubi), which is 30 centimetres long and weighs only c. 100 grams, to the huge rhinoceros hornbill (Buceros rhinoceros) in Malaysia and Indonesia, and the southern ground-hornbill (Bucorvus leadbeateri) in Africa, both measuring c. 1.2 metres, the ground-hornbill weighing up to 6.2 kilos.
These birds feed mainly on various fruits, especially of fig trees (Ficus), but they also eat small animals like insects, scorpions, lizards, and snakes. When termites are swarming, hornbills often gather around termite mounds to eat the forthcoming insects.
Hornbills nest in hollow trees and are thus dependent on old growth forests. For this reason, many species have declined alarmingly during the last hundred years or so, as ever-increasing areas of tropical forests have been cleared by humans.
The breeding habit of hornbills is very peculiar. When the female has laid her eggs inside a hollow tree, she will plaster the nest hole from inside, using her own guano which hardens in the air. Sometimes the male will help plastering the hole by bringing clay to the nest. This plaster makes it difficult for enemies like monkeys to eat eggs and young. Only a small opening is left, through which the male feeds the female during the entire incubation period. In some species, the female breaks the plaster, when the young are half grown, and then help the male feed the young – which will plaster the hole with their own guano when their mother has left! In other species, the female remains in the nest, until the young are full-grown. Meanwhile, the male brings food to all of them.
Hornbills often call simultaneously, their powerful call carrying quite a distance. This picture shows calling silvery-cheeked hornbills (Bycanistes brevis), gathered in a tree, Lake Manyara National Park, Tanzania. (Photo copyright © by Kaj Halberg)
Trumpeter hornbill (Bycanistes bucinator), feeding on fruits of a fig tree, a favoured food item among these birds. – Zimbabwe. (Photo copyright © by Kaj Halberg)
This silvery-cheeked hornbill is also feeding on fig fruits, Wondo Genet, Ethiopia. (Photo copyright © by Kaj Halberg)
When termites are swarming, hornbills often gather around termite mounds to eat the forthcoming insects. – This picture shows a silvery-cheeked hornbill in Lake Manyara National Park, Tanzania. (Photo copyright © by Kaj Halberg)
One of the largest hornbills is the rhinoceros hornbill (Buceros rhinoceros), measuring more than 1.2 metres. It is found in Malaysia and Indonesia. (Photo copyright © by Kaj Halberg)
The black-and-white-casqued hornbill (Bycanistes subcylindricus) lives in rain forests. This one was photographed in Kakamega Forest, western Kenya. (Photo copyright © by Kaj Halberg)
Two species of hornbill, the huge ground-hornbills, differ quite a lot from other hornbills. They live in grassland with scattered trees, in which they nest, but otherwise they spend most of their time foraging among short grass for lizards, snakes, and other smaller animals.
These huge hornbills are restricted to Africa. The southern ground-hornbill (Bucorvus leadbeateri) is found from Kenya southwards to northern South Africa, Namibia, and Angola, whereas the Abyssinian, or northern ground-hornbill (B. abyssinicus), is endemic to Ethiopia.
As their name implies, ground-hornbills spend most of their time on the ground. This southern ground-hornbill was observed in Lake Manyara National Park, Tanzania. (Photo copyright © by Kaj Halberg)
Southern ground-hornbill, swallowing a beetle or some other insect, Serengeti National Park, Tanzania. (Photo copyright © by Kaj Halberg)
Abyssinian ground-hornbill, photographed near the Genale River, Ethiopia. It differs from the southern species by its blue wattles. (Photo copyright © by Kaj Halberg)
In Africa, there is a bewildering array of small hornbills of the genera Tockus and Lophoceros, in several languages called toko. Formerly, smaller hornbills of the Indian Subcontinent were also included in Tockus, but have recently been moved to a genus of their own, Ocyceros.
The complicated classification of red-billed hornbills is dealt with in a separate caption below.
Eastern yellow-billed hornbills (Tockus flavirostris), Samburu National Park, Kenya. (Photo copyright © by Kaj Halberg)
Southern yellow-billed hornbill (Tockus leucomelas), Etosha National Park, Namibia. (Photo copyright © by Kaj Halberg)
A pair of southern yellow-billed hornbills, greeting each other in the morning sun, Matobo National Park, Zimbabwe. (Photo copyright © by Kaj Halberg)
Southern yellow-billed hornbills, feeding on insects in elephant dung, Kruger National Park, South Africa. (Photo copyright © by Kaj Halberg)
Female von der Decken’s hornbill (Tockus deckeni), Awash National Park, Ethiopia. (Photo copyright © by Kaj Halberg)
Jackson’s hornbill (Tockus jacksoni), Lake Baringo, Kenya. (Photo copyright © by Kaj Halberg)
African grey hornbill (Lophoceros nasutus), observed near the Blue Nile, Ethiopia. (Photo copyright © by Kaj Halberg)
Hemprich’s hornbill (Lophoceros hemprichii), Yabello, southern Ethiopia. (Photo copyright © by Kaj Halberg)
Indian grey hornbill (Ocyceros birostris), Keoladeo National Park, Rajasthan. (Photo copyright © by Kaj Halberg)
Male Malabar grey hornbill (Ocyceros griseus) in morning light, Mahaveer Wildlife Sanctuary, Goa, India. (Photo copyright © by Kaj Halberg)
Previously, all red-billed hornbills were regarded as a single species, Tockus erythrorhynchus. Following recent genetic studies, some authorities claim that it should be split into five separate species:
Northern red-billed hornbill (T. erythrorhynchus), found from southern Mauritania eastwards to Eritrea and Somalia, and thence south to Kenya and northern Tanzania.
Western red-billed hornbill (T. kempi), distributed from southern Mauritania through Senegal and Gambia to western Mali.
Tanzanian red-billed hornbill (T. ruahae), restricted to central and western Tanzania.
Southern red-billed hornbill (T. rufirostris), found from Angola and Namibia eastwards to Zambia, and thence south to north-eastern South Africa.
Damara red-billed hornbill (T. damarensis), restricted to southern Angola and northern and western Namibia.
Many authorities, including the IUCN Red List of Threatened Species 2016, and Handbook of the Birds of the World (Lynx Editions), still consider these birds as belonging to a single species.
Northern red-billed hornbill (Tockus (e.) erythrorhynchus), feeding in a grassy area, Tarangire National Park, Tanzania. (Photo copyright © by Kaj Halberg)
Southern red-billed hornbill (Tockus (e.) rufirostris), Matobo National Park, Zimbabwe. (Photo copyright © by Kaj Halberg)
Hornbills and people
Throughout their distribution area, hornbills used to play an important role in tribal mythology, and their casque and feathers were widely used as ornaments. The casque of the helmeted hornbill (Rhinoplax vigil) of Southeast Asia is very heavy. Known as ho-ting, it is much praised by the Chinese, utilized for carving. Hornbill heads are often used as an ingredient in traditional Asian medicine.
In Borneo, a young girl of the Punan tribe performs a dance, with fans of hornbill feathers attached to her wrists. – Read more about the Punan people on this website, see Travel episodes: Borneo 1975 – Canoe trip with Punan tribals. (Photo copyright © by Kaj Halberg)
These street vendors in Kathmandu, Nepal, have displayed some of their goods, utilized as ingredients in traditional medicine, such as heads of hornbills and ibises, scorpions, and dried lizards. (Photos copyright © by Kaj Halberg)
In tourist areas, hornbills often become remarkably tame.
Danish biologist Thomas Bregnballe, hand-feeding a northern red-billed hornbill (Tockus erythrorhynchus), Samburu National Park, Kenya. (Photo copyright © by Kaj Halberg)
Southern yellow-billed hornbills (Tockus leucomelas), gathered around tourists, who are having breakfast, Kruger National Park, South Africa. (Photo copyright © by Kaj Halberg)
(Uploaded February 2016)
(Revised January 2019)