VU
White-faced Partridge Arborophila orientalis



Taxonomy

Taxonomic source(s)
del Hoyo, J., Collar, N.J., Christie, D.A., Elliott, A. and Fishpool, L.D.C. 2014. HBW and BirdLife International Illustrated Checklist of the Birds of the World. Volume 1: Non-passerines. Lynx Edicions BirdLife International, Barcelona, Spain and Cambridge, UK.
Mees, G.F. 1996. Geographical variation in birds of Java. Publications of the Nuttall Ornithological Club 26(I-viii): 1-119.

IUCN Red List criteria met and history
Red List criteria met
Critically Endangered Endangered Vulnerable
- - B1ab(ii,iii,v)

Red List history
Year Category Criteria
2024 Vulnerable B1ab(ii,iii,v)
2016 Vulnerable A2cd+3cd+4cd;B1ab(ii,iii,v)
2012 Vulnerable A2cd+3cd+4cd;B1ab(ii,iii,v)
2008 Vulnerable A2c; A3c; A4c; B1a+b(ii,iii,v)
2004 Vulnerable
2000 Vulnerable
1994 Not Recognised
1988 Not Recognised
Species attributes

Migratory status not a migrant Forest dependency high
Land-mass type shelf island
Average mass -
Range

Estimate Data quality
Extent of Occurrence (breeding/resident) 5,000 km2 medium
Area of Occupancy (breeding/resident) 2,100 km2
Number of locations 6-20 -
Severely fragmented? no -
Population
Estimate Data quality Derivation Year of estimate
Population size 4000-20000, 10000-20000 mature individuals poor suspected 2023
Population trend decreasing poor inferred 2010-2026
Rate of change over the past 10 years/3 generations (longer of the two periods) 5-20% - - -
Rate of change over the future 10 years/3 generations (longer of the two periods) 5-20% - - -
Rate of change over the past & future 10 years/3 generations (longer of the two periods) 5-20% - - -
Generation length 5.37 years - - -
Number of subpopulations 3 - - -
Percentage of mature individuals in largest subpopulation 40-60, 50% - - -

Population justification: Most of this species' range is not frequently visited by professional and amateur ornithologists, obscuring details of its abundance. In surveys of Mt Ijen, Mittermeier et al. (2014) found it to be fairly common (defined as 4–10 individuals encountered per day), while Eaton et al. (2021) described it as scarce. The total area of the mapped range is c.2,500 km2, of which only c.2,000 km2 now remains forested (Global Forest Watch 2023). Other range-restricted Arborophila partridges occur at low densities (Bo et al. 1998, Chhin et al. 2019) and given the trapping pressure on this species (Nijman 2022) that is likely to be depressing numbers, a density of 2–10 mature individuals (accounting too for occupancy) is precautionarily suspected. The global population size of this species is therefore suspected to number 4,000–20,000 mature individuals. Given the description of abundance given by Mittermeier et al. (2014) and reports of the numbers being traded by Nijman (2022) with no evidence of total population collapse, the upper range (10,000–20,000) of this coarse estimate is suspected of being the most accurate. Assuming the species is evenly distributed across its range, Mt Ijen probably hosts the largest subpopulation (approximately 50% of its global population size).

Trend justification: Inferred to be declining because of habitat loss and trapping. In the past three generations (16 years: 2007–2023), approximately 5.2% of forest (>50% canopy cover) has been lost from within the mapped range of A. orientalis (Global Forest Watch 2023, based on data from Hansen et al. (2013) and methods disclosed therein). As a forest-dependent species, this is thought to have had a direct impact on the population size of A. orientalis, and has likely caused a population reduction of at least 5% over the same time period. Moreover, there is evidence of trapping on a scale that is unlikely to be sustainable. Nijman (2022) estimated that approximately 700 individuals are sold each year in markets on Java and Bali. Given the estimated population size of 10,000-20,000 mature individuals used here, this level of trade is suspected to be unsustainable, and causing further ongoing declines. However, in the absence of robust demographic data, plausible lower and upper bounds are difficult to model. Overall, the species is suspected of having declined by 5–20% over the past three generations. In the absence of a clear slowing or amelioration of the current threats, this rate of decline is also suspected to occur in the window 2010–2026, and in the next three generations (2023–2039).


Country/territory distribution
Country/Territory Presence Origin Resident Breeding visitor Non-breeding visitor Passage migrant
Indonesia extant native yes

Important Bird and Biodiversity Areas (IBA)
Country/Territory IBA Name
Indonesia Dataran Tinggi Hyang
Indonesia Gunung Ijen
Indonesia Gunung Raung
Indonesia Meru Betiri
Malaysia Bintang Range
Malaysia Central Titiwangsa Range

Habitats & altitude
Habitat (level 1) Habitat (level 2) Importance Occurrence
Forest Subtropical/Tropical Moist Montane major resident
Altitude 600 - 2200 m Occasional altitudinal limits  

Threats & impact
Threat (level 1) Threat (level 2) Impact and Stresses
Agriculture & aquaculture Annual & perennial non-timber crops - Shifting agriculture Timing Scope Severity Impact
Ongoing Minority (<50%) Slow, Significant Declines Low Impact: 5
Stresses
Ecosystem degradation, Ecosystem conversion
Biological resource use Hunting & trapping terrestrial animals - Intentional use (species is the target) Timing Scope Severity Impact
Ongoing Majority (50-90%) Slow, Significant Declines Medium Impact: 6
Stresses
Species mortality
Biological resource use Logging & wood harvesting - Unintentional effects: (subsistence/small scale) [harvest] Timing Scope Severity Impact
Ongoing Minority (<50%) Slow, Significant Declines Low Impact: 5
Stresses
Ecosystem degradation

Utilisation
Purpose Scale
Pets/display animals, horticulture subsistence, national

Recommended citation
BirdLife International (2024) Species factsheet: White-faced Partridge Arborophila orientalis. Downloaded from https://datazone.birdlife.org/species/factsheet/white-faced-partridge-arborophila-orientalis on 23/11/2024.
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 23/11/2024.