VU
Pale-throated Barbet Gymnobucco vernayi



Taxonomy

Taxonomic note

Gymnobucco calvus and G. vernayi (del Hoyo and Collar 2014) were previously lumped as G. calvus following Sibley and Monroe (1990, 1993).

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.

IUCN Red List criteria met and history
Red List criteria met
Critically Endangered Endangered Vulnerable
- - C2a(ii)

Red List history
Year Category Criteria
2019 Vulnerable C2a(ii)
2016 Least Concern
2014 Least Concern
2012 Not Recognised
2008 Not Recognised
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) 38,600 km2 medium
Number of locations 11-15 -
Severely fragmented? no -
Population
Estimate Data quality Derivation Year of estimate
Population size 2500-9999 mature individuals poor inferred 2019
Population trend decreasing - inferred 1995-2020
Rate of change over the past 10 years/3 generations (longer of the two periods) 1-9% - - -
Rate of change over the future 10 years/3 generations (longer of the two periods) 1-9% - - -
Rate of change over the past & future 10 years/3 generations (longer of the two periods) 1-9% - - -
Generation length 8.5 years - - -
Number of subpopulations 1 - - -
Percentage of mature individuals in largest subpopulation 100% - - -

Population justification: Current population size calculated based on local observations (M. Mills in litt. 2019) and an expected density of <c.1.3 mature individuals/km2. True figure could be considerably lower and a more robust population estimate is needed.

Trend justification: The population is suspected to be in decline owing to loss of suitable nesting and roosting trees (del Hoyo et al. 2002). Extrapolating data from Tracewski et al. (2016) suggests that the area of forest within the species’s range is declining at a rate of approximately 8.6% over three generations (25.5 years). Therefore, if we assume that population trends are proportional to habitat trends, we can suspect that the population is declining at a rate of 8.6% over three generations. here placed in the band 1-9%. Survey work has shown the species to have disappeared from or declined at some locations (M. Mills in litt. 2018), which further supports the view that the species is in decline.


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

Important Bird and Biodiversity Areas (IBA)
Country/Territory IBA Name
Angola Chongoroi
Angola Gabela

Habitats & altitude
Habitat (level 1) Habitat (level 2) Importance Occurrence
Artificial/Terrestrial Plantations suitable resident
Artificial/Terrestrial Rural Gardens suitable resident
Forest Subtropical/Tropical Moist Lowland major resident
Forest Subtropical/Tropical Moist Montane suitable resident
Savanna Dry suitable resident
Altitude 0 - 1820 m Occasional altitudinal limits  

Threats & impact
Threat (level 1) Threat (level 2) Impact and Stresses
Agriculture & aquaculture Wood & pulp plantations - Agro-industry plantations Timing Scope Severity Impact
Ongoing Unknown Slow, Significant Declines Unknown
Stresses
Ecosystem degradation, Ecosystem conversion
Biological resource use Logging & wood harvesting - Intentional use: (large scale) [harvest] Timing Scope Severity Impact
Ongoing Unknown Slow, Significant Declines Unknown
Stresses
Ecosystem degradation
Biological resource use Logging & wood harvesting - Motivation Unknown/Unrecorded Timing Scope Severity Impact
Ongoing Unknown Unknown Unknown
Stresses
Ecosystem degradation

Utilisation
Purpose Scale
Pets/display animals, horticulture international

Recommended citation
BirdLife International (2024) Species factsheet: Pale-throated Barbet Gymnobucco vernayi. Downloaded from https://datazone.birdlife.org/species/factsheet/pale-throated-barbet-gymnobucco-vernayi 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.