• Summary
• Text account
• Data table and detailed info
• Distribution map
• Reference and further resources

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.

Red List criteria met

Critically Endangered	Endangered	Vulnerable
-	-	-

Red List history

Year	Category	Criteria
2018	Near Threatened	B1ab(v)+2ab(v); D2
2016	Near Threatened	A2ce;D2
2012	Near Threatened	A2ce;D2
2008	Near Threatened	A2c,e; D2
2004	Near Threatened
2000	Lower Risk/Near Threatened
1996	Vulnerable
1994	Vulnerable
1988	Lower Risk/Least Concern

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

	Estimate	Data quality
Extent of Occurrence (breeding/resident)	160 km2	medium
Area of Occupancy (breeding/resident)	32 km2
Severely fragmented?	no	-

	Estimate	Data quality	Derivation	Year of estimate
Population size	13000 mature individuals	poor	unknown	1984
Population trend	decreasing	poor	suspected	1998-2008
Generation length	3.5 years	-	-	-
Percentage of mature individuals in largest subpopulation	100%	-	-	-

Population justification: Engbring et al. (1990) estimated 19,619 individuals, which is rounded to 19,600 individuals here, roughly equivalent to 13,000 mature individuals; it is thought to have become scarcer since.

Trend justification: There are no actual trend data, but D. Pratt in litt (1994) considered the species to have become scarcer in recent years.

Country/Territory	Presence	Origin	Resident	Breeding visitor	Non-breeding visitor	Passage migrant
Micronesia, Federated States of	extant	native	yes

Country/Territory	IBA Name
Micronesia, Federated States of	Yap Island

Habitat (level 1)	Habitat (level 2)	Importance	Occurrence
Forest	Subtropical/Tropical Mangrove Vegetation Above High Tide Level	major	resident
Forest	Subtropical/Tropical Moist Lowland	major	resident
Altitude		Occasional altitudinal limits

Threat (level 1)	Threat (level 2)	Impact and Stresses
Climate change & severe weather	Habitat shifting & alteration	Timing		Scope		Severity		Impact
		Future		Whole (>90%)		Unknown		Unknown
		Stresses Indirect ecosystem effects, Ecosystem degradation
Invasive and other problematic species, genes & diseases	Invasive non-native/alien species/diseases - Boiga irregularis	Timing		Scope		Severity		Impact
		Future		Whole (>90%)		Very Rapid Declines		Medium Impact: 7
		Stresses Species mortality
Natural system modifications	Fire & fire suppression - Trend Unknown/Unrecorded	Timing		Scope		Severity		Impact
		Ongoing		Majority (50-90%)		Slow, Significant Declines		Medium Impact: 6
		Stresses Ecosystem degradation

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Recommended citation
BirdLife International (2024) Species factsheet: Yap Olive White-eye Zosterops oleagineus. Downloaded from https://datazone.birdlife.org/species/factsheet/yap-olive-white-eye-zosterops-oleagineus on 25/12/2024.
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 25/12/2024.