LC
Grey-backed Tailorbird Orthotomus derbianus



Taxonomy

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
2016 Least Concern
2012 Least Concern
2009 Least Concern
2008 Least Concern
2004 Least Concern
2000 Lower Risk/Least Concern
1994 Lower Risk/Least Concern
1988 Lower Risk/Least Concern
Species attributes

Migratory status not a migrant Forest dependency Medium
Land mass type Average mass 11 g
Distribution

Estimate Data quality
Extent of Occurrence breeding/resident (km2) 125,000
Number of locations -
Severely Fragmented -
Population and trend
Value Data quality Derivation Year of estimate
No. of mature individuals unknown not applicable not applicable 0
Population trend Stable suspected -
Decline (3 years/1 generation past) - - -
Decline (5 years/1 generation past) - - -
Decline (10 years/1 generation past) - - -
Decline (10 years/3 generation future) - - -
Decline (10 years/3 generation past and future) - - -
Number of subpopulations - - -
Percentage in largest subpopulation - - -

Population justification: The global population size has not been quantified, but the species is described as relatively common at most forested sites (del Hoyo et al. 2006).

Trend justification: The population is suspected to be stable in the absence of evidence for any declines or substantial threats.


Country/territory distribution
Country/Territory Occurrence status Presence Resident Breeding Non-breeding Passage
Philippines N Extant Yes

Important Bird and Biodiversity Areas (IBA)
Country/Territory IBA Name
Philippines Northern Sierra Madre Natural Park
Philippines Angat watershed
Philippines Mount Makiling
Philippines University of the Philippines Land Grants (Pakil and Real)
Philippines Quezon National Park
Philippines Mount Isarog National Park
Philippines Catanduanes Watershed Forest Reserve

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
Altitude   Occasional altitudinal limits  

Recommended citation
BirdLife International (2023) Species factsheet: Orthotomus derbianus. Downloaded from http://www.birdlife.org on 30/03/2023. Recommended citation for factsheets for more than one species: BirdLife International (2023) IUCN Red List for birds. Downloaded from http://www.birdlife.org on 30/03/2023.