EN
Chestnut-capped Thrush Geokichla interpres



Taxonomy

Taxonomic note

Geokichla interpres (del Hoyo and Collar 2016) was previously listed as Zoothera interpres.

Taxonomic source(s)
del Hoyo, J., Collar, N.J., Christie, D.A., Elliott, A., Fishpool, L.D.C., Boesman, P. and Kirwan, G.M. 2016. HBW and BirdLife International Illustrated Checklist of the Birds of the World. Volume 2: Passerines. Lynx Edicions and BirdLife International, Barcelona, Spain and Cambridge, UK.

IUCN Red List criteria met and history
Red List criteria met
Critically Endangered Endangered Vulnerable
- A2cd+3cd+4cd A2cd+3cd+4cd

Red List history
Year Category Criteria
2020 Endangered A2cd+3cd+4cd
2016 Near Threatened A2cd+3cd+4cd
2012 Near Threatened A2cd+3cd+4cd
2008 Near Threatened A2c,d; A3c,d; A4c,d
2006 Least Concern
2004 Not Recognised
2000 Not Recognised
1994 Not Recognised
1988 Not Recognised
Species attributes

Migratory status not a migrant Forest dependency medium
Land-mass type Average mass -
Range

Estimate Data quality
Extent of Occurrence (breeding/resident) 4,270,000 km2 medium
Number of locations 11-100 -
Severely fragmented? no -
Population
Estimate Data quality Derivation Year of estimate
Population size unknown - - -
Population trend decreasing poor inferred 2010-2024
Rate of change over the past 10 years/3 generations (longer of the two periods) 50-79% - - -
Rate of change over the future 10 years/3 generations (longer of the two periods) 50-79% - - -
Rate of change over the past & future 10 years/3 generations (longer of the two periods) 50-79% - - -
Generation length 4.5 years - - -
Number of subpopulations 2-100 - - -
Percentage of mature individuals in largest subpopulation 1-89% - - -

Population justification: The species is described as locally fairly common in the Lesser Sundas and Borneo, rare in Thailand and the Philippines and local and scarce in Peninsular Malaysia (del Hoyo et al. 2005). In Thailand, the species has been observed at 3-4 singers within an area of 3-4 hectares, albeit the species may have occurred at particularly high densities during surveys (Collar 2020), overestimating its true occurrence. Thus, due to high uncertainty, the global population size has not yet been quantified.

Trend justification: Based on a recent analyses by Symes et al. (2018), the species was considered to be undergoing a decline of 67.5% over a 10-year period, as estimated using data gathered between 2000-2015. Declines were attributed to the combined effect of habitat loss and trapping pressures (Symes et al. 2018, [also Tracewski et al. 2016]). This roughly equates to 78.1% decline over three generations (13.5 years; Bird et al. 2020). It is however important to note that surveys used to derive such trends were only conducted across the Greater Sundaic range, excluding quantification of any trends in the Lesser Sunda's and as such, potentially masking the true rate of decline over the species's overall range (F. Rheindt in litt. 2020). However, due to its known rarity, it is likely that the species has continued to decline at rate of at least 50%, with potential to exceed 70% over a three-generation period (as per Symes et al. 2018). Thus, the population here is suspected to be declining at a very rapid rate of 50-79%.


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

Important Bird and Biodiversity Areas (IBA)
Country/Territory IBA Name
Malaysia Crocker Range
Malaysia Danum Valley Conservation Area
Malaysia Maliau Basin Conservation Area
Malaysia Mount Kinabalu
Malaysia Mulu - Buda Protected Area
Malaysia Tabin Wildlife Reserve
Thailand Bala Sector, Hala-Bala Wildlife Sanctuary
Thailand Hala Sector, Hala-Bala Wildlife Sanctuary and Bang Lang National Park
Thailand Khao Banthad
Thailand Khao Nor Chuchi
Malaysia Endau-Rompin
Malaysia Kabili-Sepilok
Malaysia Nakawan Range

Habitats & altitude
Habitat (level 1) Habitat (level 2) Importance Occurrence
Artificial/Terrestrial Plantations marginal resident
Artificial/Terrestrial Subtropical/Tropical Heavily Degraded Former Forest suitable resident
Forest Subtropical/Tropical Moist Lowland major resident
Altitude 80 - 1000 m Occasional altitudinal limits  

Threats & impact
Threat (level 1) Threat (level 2) Impact and Stresses
Agriculture & aquaculture Annual & perennial non-timber crops - Agro-industry farming Timing Scope Severity Impact
Ongoing Majority (50-90%) Rapid Declines Medium Impact: 7
Stresses
Ecosystem degradation, Ecosystem conversion
Agriculture & aquaculture Wood & pulp plantations - Agro-industry plantations 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%) Rapid Declines Medium Impact: 7
Stresses
Species mortality
Biological resource use Logging & wood harvesting - Unintentional effects: (subsistence/small scale) [harvest] Timing Scope Severity Impact
Ongoing Minority (<50%) Rapid Declines Medium Impact: 6
Stresses
Ecosystem degradation
Natural system modifications Fire & fire suppression - Increase in fire frequency/intensity Timing Scope Severity Impact
Ongoing Minority (<50%) Slow, Significant Declines Low Impact: 5
Stresses
Ecosystem degradation, Ecosystem conversion

Utilisation
Purpose Primary form used Life stage used Source Scale Level Timing
Pets/display animals, horticulture - - non-trivial recent

Recommended citation
BirdLife International (2024) Species factsheet: Geokichla interpres. Downloaded from https://datazone.birdlife.org/species/factsheet/chestnut-capped-thrush-geokichla-interpres on 27/02/2024.
Recommended citation for factsheets for more than one species: BirdLife International (2024) IUCN Red List for birds. Downloaded from https://datazone.birdlife.org on 27/02/2024.