The flight involves stiff flaps followed by glides with the fingers splayed and upcurled. This sound has been likened to the puffing of a steam locomotive starting up. The wing beats are heavy, and the sound produced by birds in flight can be heard from a distance. The commissure of the beak is black and has a serrated edge which becomes worn with age. The male spreads the preen gland secretion, which is yellow, onto the primary feathers and bill to give them the bright yellow colour. Male hornbills indulge in aerial casque butting, with birds striking each other in flight. The casque is hollow and serves no known purpose, although it is thought to be the result of sexual selection. The back of the casque is reddish in females, while the underside of the front and back of the casque is black in males. The casque appears U-shaped when viewed from the front, and the top is concave, with two ridges along the sides that form points in the front, whence the Latin species epithet bicornis (two-horned). The most prominent feature of the hornbill is the bright yellow and black casque on top of its massive bill. Like other hornbills, they have prominent "eyelashes".
#Rhinoceros hornbill eating fig skin
Females are smaller than males and have bluish-white instead of red eyes, although the orbital skin is pinkish. It is the heaviest, but not the longest, Asian hornbill. The average weight of 7 males is 3 kg (6.6 lb) whereas that of 3 females is 2.59 kg (5.7 lb). The great hornbill is a large bird, 95–130 cm (37–51 in) long, with a 152 cm (60 in) wingspan and a weight of 2 to 4 kg (4.4 to 8.8 lb). Wood showing the eyelashes, worn bill edge and the concave casque with ridged sides Description The iris, underside of the casque and orbital skin colours vary between the sexes Illustration by English zoological artist T. Variation across populations is mainly in size, Himalayan birds being larger than those from further south, and the species is now usually considered monotypic. The subspecies from Sumatra was sometimes called cristatus.
The species was formerly broken into subspecies cavatus, from the Western Ghats, and homrai, the nominate form from the sub-Himalayan forests. The species is monotypic: no subspecies are recognised. The specific bicornis is Latin and means "two-horned".
The genus name is from Latin becerus meaning "horned like an ox" which in turn is from the Ancient Greek boukerōs which combines bous meaning "ox" with kerōs meaning "horn". Linnaeus specified the location as China. He placed it with the rhinoceros hornbill in the genus Buceros and coined the binomial name Buceros bicornis. The great hornbill was formally described by the Swedish naturalist Carl Linnaeus in 1758 in the tenth edition of his Systema Naturae. The Government of Kerala declared it as the official Kerala state bird. Due to its large size and colour, it is important in many tribal cultures and rituals. It is known to have lived for nearly 50 years in captivity. It has been listed as Vulnerable on the IUCN Red List since 2018. It is predominantly frugivorous, but also preys on small mammals, reptiles and birds.
It occurs in the Indian subcontinent and Southeast Asia. The great hornbill ( Buceros bicornis), also known as the concave-casqued hornbill, great Indian hornbill or great pied hornbill, is one of the larger members of the hornbill family.
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