
Photo: Surabhi Srivastava · CC BY 4.0 (May be cropped or resized)
Pseudibis papillosa
Habitat
Large stick platforms 35–60cm across; also on buildings in small towns
Clutch size
2–4 pale bluish-green eggs
The red-naped ibis builds mainly large stick platforms 35 to 60cm across and 10 to 15cm deep, loosely lined with straw, with fresh material added even while the eggs are being incubated. The eggs are two to four and pale bluish green. In small towns it hunts adult rock pigeons and takes their eggs from nests on buildings (Wikipedia, general species account).
The only source read for the Bhutan guide gives these nesting and hunting details. No plumage, range or diet information beyond that was found, so none is stated, and its occurrence in Bhutan is flagged for checking.