Bare-faced Bulbul Nok hualon Scientific name definitions

19 cm; 33–41 g. A dull olive to grayish-brown bulbul characterized by near absence of contour feathering  on top and side of head. Adult male has bare skin of head mostly pale orange-pink, broadly bluish around orbital area and on lores; rearmost side of head has a tuft of whitish, upswept feathers, and slightly elongated and erectile feathers around neck may form nuchal collar; upperparts, including uppertail, drab olive, upperwing brownish-gray or gray with olive tips or edges of feathers; chin and throat off-white, underparts fawn-gray, whiter on chin and throat, olive undertail-coverts; iris very dark brown; bill black; legs mostly black, tarsus may have pinkish areas. Sexes similar, female smaller and slightly paler than male, especially on chin and throat, has sparser and paler feathering on crown. Juvenile undescribed.

Limestone karst, both massive and as small isolates rising from the plains, from Luang Prabang to Salavan Provinces, in C Laos.

Almost certainly entirely restricted to limestone karst terrain  with scattered vegetation of stunted deciduous trees and bushes, and with steep and mostly barren ground with little ground vegetation or soil.

Fruit (common in the habitat) probably constitutes principal food; seen to eat figs (Ficus) and berries of the woody shrub Bridelia. Predominantly arboreal , but may also perch on rocks in the rather open habitat. Seen singly and in small groups. Recorded catching insects in flight, sallying from a perch.

Commonest vocalization a brief series of whistled, dry bubbling notes, sometimes followed by a longer series of notes that accelerates towards end; also, before taking off, a similar but more excited trill, initially on rising scale, sometimes followed (when bird airborne) by very short ascending trills.

Not globally threatened. Restricted-range species: present in Southern Laos Secondary Area. Population size not known. Presumably occurs across entire limestone belt of C Laos (confirmed records from its S extent and, almost, from its N extent), and perhaps into adjacent C Vietnam. Extensive areas of limestone karst with presumably suitable habitat are legally protected in Phou Hinpoun and Hin Namno National Protected Areas. These comprise a more or less cohesive series of rugged and, to date, practically impenetrable karst. Wholesale loss of habitat in these areas is considered unlikely, due to difficulty of terrain.