• 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
-	-	D1

Red List history

Year	Category	Criteria
2023	Near Threatened	D1
2016	Vulnerable	D1+2
2012	Vulnerable	D1+2
2008	Vulnerable	D1; D2
2006	Vulnerable
2004	Vulnerable
2000	Vulnerable
1996	Vulnerable
1994	Vulnerable
1988	Threatened

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

	Estimate	Data quality
Extent of Occurrence (breeding/resident)	84 km2	medium
Area of Occupancy (breeding/resident)	84 km2
Severely fragmented?	no	-

	Estimate	Data quality	Derivation	Year of estimate
Population size	900-1650 mature individuals	poor	inferred	2022
Population trend	stable	poor	suspected	-
Generation length	2.53 years	-	-	-
Number of subpopulations	1	-	-	-
Percentage of mature individuals in largest subpopulation	100%	-	-	-

Population justification: Confined to a very small area on Kolombangara, from 1,200 m to (presumably) the summit of Mt Veve at 1,740 m (C. Filardi in litt. 2012). Its range therefore comprises only 21 km². It is said to be uncommon (Dutson 2011) or rare (Buckingham et al. 1992) but data (eBird 2022) suggest it is encountered no less regularly than other leaf-warblers in the region and two visits in 2017 and 2019 found the species with relative ease in a small area once suitable elevations were reached (J. Bergmark pers. comm. 2022). Phylloscopus warblers typically occur at a relatively high density, with other montane species recorded at densities of 55-210 birds/km² (Evans et al. 1991, 1993; Marsden 1998). Adopting the 25th and 75th percentile of this range, and assuming an occupancy of c. 70%, the population is inferred to number c. 1,400-2,500 birds, or c. 900-1,650 mature individuals. These numbers are broadly congruent with Buckingham et al. (1992) who suggested the population size numbered 900-2,100, although it is unclear how this figure was arrived at, or whether it refers to individuals or mature individuals.

Trend justification: Suspected to be stable. Reports have consistently suggested no threat is acting on this species (Buckingham et al. 1992, G. Dutson in litt. 2012, J. Bergmark in litt. 2022) removing it from logging risk. Although the data are too sparse to analyse, the species appears to have become no scarcer comparing eBird (2022) data across time series over the last ten years.

Country/Territory	Presence	Origin	Resident	Breeding visitor	Non-breeding visitor	Passage migrant
Solomon Islands	extant	native	yes

Country/Territory	IBA Name
Solomon Islands	Kolombangara Upland Forest

Habitat (level 1)	Habitat (level 2)	Importance	Occurrence
Forest	Subtropical/Tropical Moist Montane	major	resident
Altitude	1200 - 1740 m	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
Geological events	Avalanches/landslides	Timing		Scope		Severity		Impact
		Ongoing		Minority (<50%)		Causing/Could cause fluctuations		Low Impact: 5
		Stresses Ecosystem degradation
Invasive and other problematic species, genes & diseases	Invasive non-native/alien species/diseases - Named species	Timing		Scope		Severity		Impact
		Ongoing		Whole (>90%)		Negligible declines		Medium Impact: 6
		Stresses Reduced reproductive success
Invasive and other problematic species, genes & diseases	Invasive non-native/alien species/diseases - Sus domesticus	Timing		Scope		Severity		Impact
		Ongoing		Whole (>90%)		Negligible declines		Medium Impact: 6
		Stresses Species mortality

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Recommended citation
BirdLife International (2024) Species factsheet: Kolombangara Leaf-warbler Phylloscopus amoenus. Downloaded from https://datazone.birdlife.org/species/factsheet/kolombangara-leaf-warbler-phylloscopus-amoenus 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.