Grand Comoro Bulbul Hypsipetes parvirostris


Taxonomic note

Hypsipetes parvirostris and H. moheliensis (del Hoyo and Collar 2016) were previously lumped as H. parvirostris following Dowsett & Forbes-Watson (1993) and Sibley & Monroe (1990, 1993).


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
- - -

Red List history
Year Category Criteria
2022 Near Threatened B1ab(ii,iii)+2ab(ii,iii)
2016 Vulnerable C2a(ii)
Species attributes

Migratory status not a migrant Forest dependency medium
Land-mass type Average mass 60 g

Estimate Data quality
Extent of Occurrence (breeding/resident) 1,300 km2
Area of Occupancy (breeding/resident) 1,252 km2
Severely fragmented? no -
Estimate Data quality Derivation Year of estimate
Population size 2500-9999 mature individuals poor suspected 2016
Population trend decreasing - suspected 2015-2027
Rate of change over the past 10 years/3 generations (longer of the two periods) 1-5% - - -
Rate of change over the future 10 years/3 generations (longer of the two periods) 1-5% - - -
Rate of change over the past & future 10 years/3 generations (longer of the two periods) 1-9% - - -
Generation length 3.83 years - - -
Number of subpopulations 1 - - -
Percentage of mature individuals in largest subpopulation 100% - - -

Population justification: This species is reasonably common (with encounter rates of 25 birds/hr [Safford 2013]), although less common above 1,000m (Louette 2004). Based on descriptions of abundance, and assuming only a proportion of its restricted range is inhabited, this species is not thought to number more than 10,000 mature individuals. Therefore, it is tentatively placed in the range of 2,500-9,999 mature individuals.

Trend justification: The population is suspected to be slowly declining owing to on-going habitat loss and degradation. Deforestation rates have been low over the past three generations, amounting to 4% (Global Forest Watch 2021, using Hansen et al. [2013] data and methods disclosed therein). Given that the species can tolerate degraded areas and clearings, any population decline is likely to be slower than this, therefore the decline is not expected to exceed 5% over three generations.

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

Important Bird and Biodiversity Areas (IBA)
Country/Territory IBA Name
Comoros Karthala Mountains
Comoros La Grille Mountains

Habitats & altitude
Habitat (level 1) Habitat (level 2) Importance Occurrence
Artificial/Terrestrial Subtropical/Tropical Heavily Degraded Former Forest suitable resident
Forest Subtropical/Tropical Moist Lowland major resident
Forest Subtropical/Tropical Moist Montane suitable resident
Altitude 500 - 1000 m Occasional altitudinal limits (max) 1850 m

Threats & impact
Threat (level 1) Threat (level 2) Impact and Stresses
Agriculture & aquaculture Annual & perennial non-timber crops - Small-holder farming Timing Scope Severity Impact
Ongoing Minority (<50%) Negligible declines Low Impact: 4
Ecosystem degradation, Ecosystem conversion

Recommended citation
BirdLife International (2024) Species factsheet: Hypsipetes parvirostris. Downloaded from https://datazone.birdlife.org/species/factsheet/grand-comoro-bulbul-hypsipetes-parvirostris on 21/02/2024.
Recommended citation for factsheets for more than one species: BirdLife International (2024) IUCN Red List for birds. Downloaded from https://datazone.birdlife.org on 21/02/2024.