Buceros bicornis
Red List Status: VU – Vulnerable, criteria A3cd+4cd (IUCN 2020)
Distribution: South-west India; south Himalayas and south China into Indochina south to Peninsular Malaysia and Sumatra.
Description: Male 121-150 cm, female 112-125 cm. Male 2610-3900 g; female 2157-3350 g. Very large hornbill with black band across white tail, black wings with white trailing edge. White plumage areas on head, neck, wing coverts and base of tail are usually cosmetically stained yellow with preen oil. Male has black-rimmed red eyes and flat casque, forked at the front with black edges. Female has white eyes with a red rim that flushes brighter while breeding and smaller casque without black lines. Juvenile has blue-grey eyes; the small casqueless bill grows to maturity over five years.
Voice: The call is a loud and reverberating kok, often as a pair duet, that can be heard over 800 meters in the forest, along with other guttural sounds.
Habits: Found in primary evergreen and moist deciduous forests. Occurs at sea level, but prefers hills further inland between 600 and 1,000 m elevation, in the Himalayan foothills and northern Thailand recorded to 2,000 m. Feeds in the canopy of large trees, often a resident pair or a family group together. Although largely sedentary, it ranges somewhat for food outside of breeding season. Flocks might congregate in fruiting trees or at communal evening roosts. Occasionally descends to the ground to pick up fallen fruits. Roams widely in search of fruiting trees, sometimes crossing high over open areas. It flies with heavy wing-beats, 3-4 flaps and a long glide; the massive wings produce a loud whooshing sound. In Khao Yai NP food eaten and delivered to the nest is mainly fruit, especially many different kinds of figs but also lipid-rich fruits such as those of the Meliaceae (Aglaia, Dysoxylum, Chisocheton spp). However, Polyalthia viridis (Annonaceae) and Cinnamomum subavenum (Lauraceae) and Horsfieldia glaba (Myristicaceae) appear to be high among non-fig fruit items. Flowers and buds are also taken, as well as many animals such as small mammals, birds and reptiles, as well as large insects and other arthropods. When hunting, this hornbill hops along the branches and pokes into crevices and barks for prey, grabbing it with its huge bill and tossing it in the air for a better grip, before flying off to deliver it to the nest. Generally, in the nonbreeding season there are fewer lipid-rich fruits available, and it relies even more on figs.
