Great Hornbill Buceros bicornis Scientific name definitions

95–105 cm; male 2600–3400 g, female 2155–3350 g. Very large, pied hornbill with black band across white tail ; long, deep bill, and white plumage areas of head, neck and wing-coverts, usually cosmetically coloured yellow with preen oil. Male has flat casque double-pointed at front, with black rim; black-rimmed red eyes . Female smaller, casque smaller  and without black; eyes white, with red rim that flushes brighter when breeding. Juvenile with blue-grey eyes, and small casqueless bill which grows to maturity over five years.

Western Ghats (SW India); S Himalayas (Garhwal and Kumaon) E to NC Myanmar, S China (W Yunnan) and Vietnam, and S to Malay Peninsula and Sumatra.

Large tracts of primary evergreen forest, but will cross open areas between forest patches; occurs at up to 2000 m.

Largely sedentary; ranges more widely for food in non-breeding season, but without any regular pattern.

Mainly fruit , rarely flowers and buds; also many large insects and other arthropods, besides various small reptiles, birds and mammals. Eats many species of fig , which comprised 73% of food delivered to nests in India; also drupes of Vitex, and various other lipid-rich fruits from at least 18 genera. Feeds mainly in canopy , but will descend to ground for fallen fruit. Usually feeds in pairs or family groups, but sometimes gathers in numbers at fruiting trees and roosts in flocks of up to 200 in non-breeding season.

A series of short, resonant, growling “rroh”  calls  . In flight, pairs call antiphonally  on two different pitches “rroh-rroh...”.

Lays in Jan–Apr across whole range. Monogamous and territorial, sometimes engaging in aerial casque-butting. Nest in natural hole 8–35 m up in larger forest tree (1 James, D.A. and Kannan, R. (2009). Nesting habitat of the Great Hornbill (Buceros bicornis) in the Anaimalai Hills of southern India. Wilson Journal of Ornithology. 121(3): 485–492. Close ), often Dipterocarpus or Syzygium species, rarely in hole in limestone cliff; entrance often elongate, sealed by both sexes. Usually two eggs (1–4), laid at intervals of 4–5 days, after pre-laying period 1–4 days; incubation 38–40 days, in captivity 35–37 days recorded; chick 45–50 g at hatching; female and chicks fed in nest by male , with up to 185 items daily, or 43 g per hour, regurgitated from gullet; female moults remiges and rectrices once enclosed, usually emerges when oldest chick 14–59 days old, well before it fledges; fledging 72–96 days; total nesting cycle 102–140 days; in captivity, however, recorded nestling period 70–74 days, female emerging few days before chick and after 4 months of enclosure, having undergone successional and incomplete moult of main wing and tail feathers. Recorded longevity in captivity over 41 years.

VULNERABLE. CITES I. Previously considered Near Threatened. Inhabits wide range, but declining in many areas, especially in W India (estimated 3500 birds in 100 forest patches) and Sumatra. Family home range may extend over more than 600 km², in which case species never really abundant locally; in Thailand, however, breeding home range only 3·7 km² and non-breeding 14·7 km². Occurs in several protected areas throughout range, e.g. Indira Gandhi (Top Slip) and Periyar National Parks (India), Khao Yai National Park (Thailand) and Way Kambas National Park (Sumatra). Habitat degradation is main cause of decline, in addition to population fragmentation and widespread loss of large nest trees; also subject to hunting and trapping in most areas, for food, tribal medicinal use and trade. Has been bred several times in captivity.