Bucerotidae – Hornbills
The Bucerotidae or Hornbills are a family of bird found in tropical and subtropical Africa, Asia and Melanesia. They are characterized by a long, down-curved bill which is frequently brightly coloured and sometimes has a casque on the upper mandible. Both the common English and the scientific name of the family refer to the shape of the bill, ‘buceros’ being ‘cow horn’ in Greek. Hornbills have a two-lobed kidney. They are the only birds in which the first and second neck vertebrae (the atlas and axis respectively) are fused together; this probably provides a more stable platform for carrying the bill. The family is omnivorous, feeding on fruit and small animals. They are monogamous breeders nesting in natural cavities in trees and sometimes cliffs. A number of species of hornbill are threatened with extinction, mostly insular species with small ranges.
Hornbills show considerable variation in size, ranging from the Black Dwarf Hornbill Tockus hartlaubi, at 102 grams and 30cm. Males are always bigger than the females, though the extent to which this is true varies according to species. The extent of sexual dimorphism also varies with body parts. For example, the difference in body mass between males and females is 1% to 17%, but the variation is 8% to 30% for bill length and 1% to 21% in wing length.
The most distinctive feature of the hornbills is the heavy bill, supported by powerful neck muscles as well as by the fused vertebrae. The large bill assists in fighting, preening, constructing the nest, and catching prey. A feature unique to the hornbills is the casque, a hollow structure that runs along the upper mandible. In some species it is barely perceptible and appears to serve no function beyond reinforcing the bill. In other species it is quite large, is reinforced with bone, and has openings between the hollow centre, allowing it to serve as a resonator for calls. In the Helmeted Hornbill the casque is not hollow but is filled with hornbill ivory and is used as a battering ram in dramatic aerial jousts. Aerial casque-butting has also been reported in the Great Hornbill.
Their plumage is typically black, grey, white, or brown, and is frequently offset by bright colours on the bill, or by patches of bare coloured skin on the face or wattles. Some species exhibit sexual dichromatism. The calls of hornbills are loud and vary distinctly between different species. They possess binocular vision, although unlike most birds with this type of vision, the bill intrudes on their visual field. This allows them to see their own bill tip and aids in precision handling of food objects with their bill. The eyes are also protected by large eyelashes which act as a sunshade. They are diurnal, generally travelling in pairs or small family groups. Larger flocks sometimes form outside the breeding season. The largest assemblies of hornbills form at some roosting sites, where as many as 2400 individual birds may be found.
According to the IOC there are 59 species of typical Hornbills in the family Bucerotidae; they are below. The HBW says 14 genera, 54 species, 78 taxa. The 59 species are:
Tanzanian Red-billed Hornbill Tockus ruahae
Western Red-billed Hornbill Tockus kempi
Damara Red-billed Hornbill Tockus damarensis
Southern Red-billed Hornbill Tockus rufirostris
Northern Red-billed Hornbill Tockus erythrorhynchus
Monteiro’s Hornbill Tockus monteiri
Von der Decken’s Hornbill Tockus deckeni
Jackson’s Hornbill Tockus jacksoni
Southern Yellow-billed Hornbill Tockus leucomelas
Eastern Yellow-billed Hornbill Tockus flavirostris
Bradfield’s Hornbill Lophoceros bradfieldi
Crowned Hornbill Lophoceros alboterminatus
African Pied Hornbill Lophoceros fasciatus
Hemprich’s Hornbill Lophoceros hemprichii
African Grey Hornbill Lophoceros nasutus
Red-billed Dwarf Hornbill Lophoceros camurus
Pale-billed Hornbill Lophoceros pallidirostris
Piping Hornbill Bycanistes fistulator
Trumpeter Hornbill Bycanistes bucinator
Brown-cheeked Hornbill Bycanistes cylindricus
White-thighed Hornbill Bycanistes albotibialis
Black-and-white-casqued Hornbill Bycanistes subcylindricus
Silvery-cheeked Hornbill Bycanistes brevis
Black-casqued Hornbill Ceratogymna atrata
Yellow-casqued Hornbill Ceratogymna elata
Black Dwarf Hornbill Horizocerus hartlaubi
White-crested Hornbill Horizocerus albocristatus
White-crowned Hornbill Berenicornis comatus
Rhinoceros Hornbill Buceros rhinoceros
Great Hornbill Buceros bicornis
Rufous Hornbill Buceros hydrocorax
Helmeted Hornbill Rhinoplax vigil
Palawan Hornbill Anthracoceros marchei
Oriental Pied Hornbill Anthracoceros albirostris
Malabar Pied Hornbill Anthracoceros coronatus
Sulu Hornbill Anthracoceros montani
Black Hornbill Anthracoceros malayanus
Malabar Grey Hornbill Ocyceros griseus
Sri Lanka Grey Hornbill Ocyceros gingalensis
Indian Grey Hornbill Ocyceros birostris
Tickell’s Brown Hornbill Anorrhinus tickelli
Austen’s Brown Hornbill Anorrhinus austeni
Bushy-crested Hornbill Anorrhinus galeritus
Rufous-necked Hornbill Aceros nipalensis
Blyth’s Hornbill Rhyticeros plicatus
Narcondam Hornbill Rhyticeros narcondami
Wreathed Hornbill Rhyticeros undulatus
Sumba Hornbill Rhyticeros everetti
Plain-pouched Hornbill Rhyticeros subruficollis
Knobbed Hornbill Rhyticeros cassidix
Walden’s Hornbill Rhabdotorrhinus waldeni
Writhed Hornbill Rhabdotorrhinus leucocephalus
Sulawesi Hornbill Rhabdotorrhinus exarhatus
Wrinkled Hornbill Rhabdotorrhinus corrugatus
Luzon Hornbill Penelopides manillae
Mindoro Hornbill Penelopides mindorensis
Mindanao Hornbill Penelopides affinis
Samar Hornbill Penelopides samarensis
Visayan Hornbill Penelopides panini
African Grey Hornbill Tockus nasutusSpecies AccountThe African grey hornbill (Tockus nasutus) is a member of the hornbill family of tropical near-passerine birds found in the Old World. It is a widespread and common resident breeder in much of sub-Saharan Africa and into Arabia.
Black Hornbill Anthracoceros malayanusSpecies AccountSound archive and distribution map.
Black Hornbill Anthracoceros malayanusSpecies AccountThe black hornbill (Anthracoceros malayanus) is a species of bird of the hornbill family Bucerotidae. It lives in Asia in Brunei Darussalam, Indonesia, Malaysia, Singapore, Thailand.
Blyth's Hornbill Rhyticeros plicatusSpecies AccountSound archive and distribution map.
Blyth's Hornbill Rhyticeros plicatusSpecies AccountBlyth's hornbill (Rhyticeros plicatus), also known as the Papuan hornbill, is a large hornbill inhabiting the forest canopy in Wallacea and Melanesia. Its local name in Tok Pisin is kokomo.
Crowned Hornbill Tockus alboterminatusSpecies AccountThe crowned hornbill (Tockus alboterminatus) is an African hornbill.
Eastern Yellow-billed Hornbill Tockus flavirostrisSpecies AccountSound archive and distribution map.
Eastern Yellow-billed Hornbill Tockus flavirostrisSpecies AccountThe eastern yellow-billed hornbill (Tockus flavirostris), also known as the northern yellow-billed hornbill, is a species of hornbill in the Bucerotidae family. It is found in Djibouti, Eritrea, Ethiopia, Kenya, Somalia, South Sudan, Tanzania, and Uganda. It resembles the southern yellow-billed hornbill, but has blackish (not pinkish) skin around the eyes.
Knobbed Hornbill Rhyticeros cassidixSpecies AccountThe knobbed hornbill (Rhyticeros cassidix), also known as Sulawesi wrinkled hornbill, is a colourful hornbill native to Indonesia. The species is sometimes placed in the genus Aceros. The knobbed hornbill is the faunal symbol of South Sulawesi province.
Knobbed Hornbill Rhyticeros cassidixSpecies AccountSound archive and distribution map.
Northern Red-billed Hornbill Tockus erythrorhynchusSpecies AccountThe red-billed hornbills are a group of hornbills found in savanna and woodland of sub-Saharan Africa. They are now usually split into five species.
Northern Red-billed Hornbill Tockus erythrorhynchusSpecies AccountSound archive and distribution map.
Palawan Hornbill Anthracoceros marcheiSpecies AccountSound archive and distribution map.
Palawan Hornbill Anthracoceros marcheiSpecies AccountThe Palawan hornbill (Anthracoceros marchei), known as Talusi in the Filipino language, is a smallish (approximately 70 centimetres (28 in) long) forest-dwelling bird. Its plumage is predominantly black, with a white tail, a dark green gloss on its upper parts and a large creamy-white beak with a casque typical of the hornbill family. It emits loud calls which can be transcribed as kaaww and kreik-kreik.
Rufous-necked Hornbill Aceros nipalensisSpecies AccountSound archive and distribution map.
Rufous-necked Hornbill Aceros nipalensisSpecies AccountThe rufous-necked hornbill (Aceros nipalensis) is a species of hornbill in the northeastern India, especially in Arunachal Pradesh, Indian Subcontinent and Southeast Asia. Numbers have declined significantly due to habitat loss and hunting, and it has been entirely extirpated from Nepal.
Sulu Hornbill Anthracoceros montaniSpecies AccountSound archive and distribution map.
Sulu Hornbill Anthracoceros montaniSpecies AccountThe Sulu hornbill or Montano's hornbill (Anthracoceros montani) is a species of hornbill in the Bucerotidae family. It is endemic to the Philippines. Its natural habitat is subtropical or tropical moist montane forests.
Trumpeter Hornbill Bycanistes bucinatorSpecies AccountSound archive and distribution map.
Trumpeter Hornbill Bycanistes bucinatorSpecies AccountThe trumpeter hornbill is a gregarious bird, usually living in groups of two to five individuals, although sometimes as many as fifty. This hornbill is a locally common resident of the tropical evergreen forests of Burundi, Mozambique, Botswana, Congo, Kenya, the Caprivi strip of Namibia and eastern South Africa, where it feeds on fruits and large insects.
Wreathed Hornbill Rhyticeros undulatusSpecies AccountSound archive and distribution map.
Wreathed Hornbill Rhyticeros undulatusSpecies AccountThe wreathed hornbill (Rhyticeros undulatus), also known as the bar-pouched wreathed hornbill, is a species of hornbill found in forests from far north-eastern India and Bhutan, east and south through mainland Southeast Asia and the Greater Sundas in Indonesia, except Sulawesi.
Writhed Hornbill Aceros leucocephalusSpecies AccountThe writhed hornbill (Aceros leucocephalus), also known as the Mindanao wrinkled hornbill, is a species of hornbill in the Bucerotidae family. It is endemic to humid forests on the Philippine islands of Mindanao, Dinagat and Camiguin Sur. It formerly included the Walden's hornbill as a subspecies, but unlike that species, both sexes of the writhed hornbill have orange-red throat and peri-ocular skin.
Number of bird species: 59
The Ecology and Conservation of Asian Hornbills| (Farmers of the Forest) | by Margaret F Kinnaird & Timothy G O'Brien | University of Chicago Press | 2008 | Hardback | 352 pages, 15 colour plates, 91 halftones, 27 line drawings, 32 tabs | ISBN: 9780226437125 Buy this book from NHBS.com
The Hornbills: Bucerotiformes| (Bird Families of the World series) | by Martin Woodcock & A C Kemp | Oxford University Press | 1996 | Hardback | 320 pages, 14 colour plates, 24 line drawings, 56 maps | ISBN: 9780198577294 Buy this book from NHBS.com
Hornbill Research FoundationWebpageThe Hornbill Research Foundation was set up following a project initiating research into the ecology of hornbills by the faculty of science, Mahidol University in 1980. The study was begun in Khao Yai National Park, Thailand and later expanded to include forests in western and southern regions. Apart from the biology and ecology of hornbills, research was also made into their range and status throughout the country. As a result, an increasing number of research workers were needed to cope with the expansion of project and the maintenance of uninterrupted record-keeping. This led to the creation of a foundation which H.R.H. Princess Mahachakri Sirinthorn was graciously pleased to name and The Hornbill Research Foundation was set up in July 1993…