Data Zone
Justification of Red List category
This species has a large range, and hence does not approach the thresholds for Vulnerable under the range size criterion (Extent of Occurrence <20,000 km2 combined with a declining or fluctuating range size, habitat extent/quality, or population size and a small number of locations or severe fragmentation). The population trend is not known, but the population is not believed to be decreasing sufficiently rapidly to approach the thresholds under the population trend criterion (>30% decline over ten years or three generations). The population size has not been quantified, but it is not believed to approach the thresholds for Vulnerable under the population size criterion (<10,000 mature individuals with a continuing decline estimated to be >10% in ten years or three generations, or with a specified population structure). For these reasons the species is evaluated as Least Concern.
Population justification
The global population size has not been quantified, but based on observations the species appears to be locally common.
Trend justification
The species is suspected to be undergoing a slow rate of decline, as, although large sections of its range may be protected by the Phou Hinpoun and Hin Namno National Protected Areas, populations outside these areas are likely to be declining owing to quarrying, hunting and habitat degradation caused by livestock grazing and firewood collection (Woxwold et al. 2009; J. Pilgrim in litt. 2009).
Pycnonotus hualon is known from Savannakhet province, Laos, although there is strong evidence that the species is also present in Bolikhamxai and Khammouan province (J. Pilgrim in litt. 2009, Woxvold et al. 2009).
This species occupies the middle and upper levels of karst outcrops, where soil is almost absent and vegetation is dominated by small deciduous trees and shrubs. It is thought to feed on fruits and berries (Woxvold et al. 2009).
This species may be undergoing a slight decline due to quarrying, hunting and habitat degradation due to livestock grazing and firewood collection (Woxvold et al. 2009).
Conservation Actions Underway
The species is thought to be present in the Phou Hinpoun and Hin Namno National Protected Areas (Woxvold et al. 2009).
Striking and diagnostic features are the near-absence of countour feathering on the face and side of the head, the presence of extensive pale blue periorbital and loral skin and orange-pink skin on the rear sides of the head and below the eye to the malar area; and loose, hair-like filoplumes along the mid-crown and reduction of anterior ear-coverts to a series of unbarbed bristles that cover the ear opening. Grey-brown body colouring and olive-toned upperparts, erectile nuchal collar, distinctly paler, fawn-grey underparts, off-white throat and olive-green remiges in folded wings. Voice. Most common vocalisation is a short (<1 second) series of whistled, dry bubbling notes.
Text account compilers
Calvert, R.
Contributors
Pilgrim, J.
Recommended citation
BirdLife International (2024) Species factsheet: Bare-faced Bulbul Nok hualon. Downloaded from
https://datazone.birdlife.org/species/factsheet/bare-faced-bulbul-nok-hualon on 29/11/2024.
Recommended citation for factsheets for more than one species: BirdLife International (2024) IUCN Red List for birds. Downloaded from
https://datazone.birdlife.org/species/search on 29/11/2024.