EN
Taita White-eye Zosterops silvanus



Taxonomy

Taxonomic note
Zosterops poliogastrus, Z. kaffensis, Z. kulalensis, Z. kikuyuensis, Z. silvanus, Z. eurycricotus, Z. mbuluensis and Z. winifredae (del Hoyo and Collar 2016) were previously lumped as Z. poliogastrus 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
- B1ab(i,ii,iii,v) B1ab(i,ii,iii,v); D1

Red List history
Year Category Criteria
2016 Endangered B1ab(i,ii,iii,v)
2012 Not Recognised
2008 Not Recognised
2006 Not Recognised
2004 Endangered
2000 Endangered
1994 Critically Endangered
1988 Not Recognised
Species attributes

Migratory status not a migrant Forest dependency Medium
Land mass type Land-mass type - continent
Average mass -
Extent of occurrence (EOO)

Estimate Data quality
Extent of Occurrence breeding/resident (km2) 2,000 medium
Number of locations -
Fragmentation -
Population and trend
Estimate Data quality Derivation Year of estimate
No. of mature individuals 250-999 poor estimated 2000
Population trend Unknown not applicable -
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 2 - - -
Largest subpopulations - - -
Generation length (yrs) 3.5 - - -

Population justification: Surveys in the late 1990s suggested a minimum population of 922 individuals in Taita Hills (Mulwa et al. 2000), roughly equivalent to 615 mature individuals. Thus it is placed in the range of 250-999 mature individuals.

Trend justification: The population is thought to be declining and becoming severely fragmented as a result of habitat loss.


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

Important Bird and Biodiversity Areas (IBA)
Country/Territory IBA Name
Kenya Taita Hills Forests
Kenya Mount Kasigau forest

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

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%) Causing/Could cause fluctuations Low Impact: 5
Stresses
Ecosystem degradation, Ecosystem conversion
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, Ecosystem conversion

Recommended citation
BirdLife International (2020) Species factsheet: Zosterops silvanus. Downloaded from http://www.birdlife.org on 28/11/2020. Recommended citation for factsheets for more than one species: BirdLife International (2020) IUCN Red List for birds. Downloaded from http://www.birdlife.org on 28/11/2020.