Meet the Rufous-necked Hornbill (Aceros nipalensis), a vulnerable hornbill species found in Bhutan, northeastern India, with fewer than 10,000 mature individuals left in the wild.
Distribution: Found in northern parts of South-east Asia; from Bhutan and north-east India, east across Myanmar to south China, north and west Thailand, north Laos and north-west Vietnam.
Description: 99-122 cm. Male 2500 g. Female 2270 g. The most colourful large hornbill, with glossy black wings with white trailing edge, mantle and top half of tail black with rest white. The male has rufous head, neck and underparts, pale ivory bill with black grooves on upper mandible, and turquoise blue orbital skin connected with cobalt blue cheeks and scarlet red pouch with dark blue line. It is distinctive within its range.
The female is all-black but can be distinguished from female Wreathed and Plain-pouched Hornbills where they overlap by blue (not reddish) bare skin around eye, red (not blue) pouch and heavy black stripes on upper mandible of bill, without visible casque, and wings with white trailing edge. Juveniles of both sexes resemble adult male in plumage but paler, and bill smaller without black grooves. The number of the grooves is somewhat related to the bird’s age.
Voice: The call is a mellow but powerful cuckoo- or pigeonlike series of descending cooing notes kup-kup … ku-kup-kup.
Habits: Occurs in extensive tracts of primary evergreen and deciduous forests. It is a lower montane species that prefers remote forested ridges and hillsides in the 600-1,800 m elevation range. Has been recorded as low as 150 m and as high as 2,200 m. It frequently forages along watercourses in hill evergreen forest. In Huai Kha Khaeng WS, Thailand, it feeds on fruits of 17 identified species or 74% of total diet dominated by Polyalthia simiarum (Annonaceae), Beilschmiedia
(Lauraceae), Knema laurina (Myristicaceae) and Aglaia cucullata (Meliaceae); figs constitute only 4% and animal food 22% of diet. Among 25 identified animal prey, crabs, snakes (Acanthosaura sp), cicadas and frogs are dominant. Feeds inside the canopies but sometimes come to the ground, particularly by creeks. It is probably sedentary and territorial; it moves in pairs or in small family groups of 4-5 birds, occasionally more, up to 15 birds. From radio tracking it seems to stay within home range of about 25 km2 all year round in hill evergreen forest of Huai Kha Khaeng WS. In non-breeding season it travels extensively up to 340 km locally in search of fruiting trees or 3.7 km daily which is not much different from daily travels in the breeding season (3.5 km). A family roosts in hill evergreen forest at 900-1,000 m a.s.l. and within 200 m from a watercourse.
