Indian Grey Hornbill

The Indian grey hornbill is a medium-sized, mostly tree-living hornbill about 61cm long, found mainly on the plains up to about 610m. It is grey over the body with a light grey or dull white belly, a black or dark grey horn, a red iris and eyelashes. The tail has a white tip and a dark subterminal band. The male has a larger casque (Wikipedia, general species account).

It is commonly sighted in pairs or small groups, with a squealing call somewhat like a black kite's. It nests in tree hollows, and the female seals the entrance with excreta and mud pellets supplied by the male, leaving only a slit through which he feeds her, and she moults her flight feathers inside. The nesting season is April to June. The source read does not name Bhutan, so its occurrence there is flagged.