Rhyticeros undulatus
Red List Status: VU – Vulnerable, criteria A3cd+4cd (IUCN 2018)
Distribution: Found in South-east Asia from southern Bhutan and north-eastern India east to Vietnam and south across Malaysia to western Indonesia east to Borneo, Java and Bali, including some nearby islands.
Description: Male 100-117 cm; female 84-98 cm. Male 2043-3650 g; female 1360-2685g. Large distinct hornbill (see Plain-pouched Hornbill for differences), male from Wrinkled Hornbill male by brown (not black) cap and nape ivory white with brown at the base (not stained bright yellow), bill with low casque and ridges on bill sides and casque, and black band across yellow pouch. Female has distinct brown ridges on white bill and black band across blue pouch. Juveniles of both sexes resemble adult male in plumage, but bill smaller without casque.
Voice: The call is a loud series of 2-3 short grunts oek-uk-uk used by both sexes, both as a soft contact call or a loud roar. The wing-beats are audible to at least 1 km, softer during rain when feathers are wet.
Habits: The Wreathed hornbill occurs in extensive tracts of primary rainforest, mainly in the foothills, but has been recorded to 2,560 m elevation. Locally it will extend into coastal forest and adjacent selectively logged forest. There it feeds mainly on fruits high in large forest trees. This hornbill is well studied; fruits of more than 30 different genera of trees have been identified and are similar to those eaten by Great Hornbill; the proportion of figs and lipid-rich drupes vary according to location and season, and ranges further when not breeding and fewer lipid-rich fruits available. Animal food is generally less than 5% of the diet, but more during the breeding season when extra protein is needed. Prey includes bird eggs and nestlings, reptiles, insects, snails, centipedes and crabs. Although mainly a canopy bird, it has been known to descend to the ground to collect fallen fruit or terrestrial prey. Mainly sedentary but will fly far and high across the forest to visit fruiting trees, also crossing open water between islands. The home range of a breeding pair is about 10 km² in Thailand. Outside of the breeding season, during the so-called flocking season, the home range extends to about 28 km² for a pair, and large flocks will gather at communal evening roosts, as many as 1,000 birds having been counted in one area.
