• 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
-	B1ab(ii,iii,v)+2ab(ii,iii,v)	B1ab(ii,iii,v)+2ab(ii,iii,v); D2

Red List history

Year	Category	Criteria
2021	Endangered	B1ab(ii,iii,v)+2ab(ii,iii,v)
2016	Least Concern
2012	Least Concern
2009	Least Concern
2008	Least Concern
2004	Least Concern
2000	Lower Risk/Least Concern
1994	Lower Risk/Near Threatened
1988	Near Threatened

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

	Estimate	Data quality
Extent of Occurrence (breeding/resident)	250 km2
Area of Occupancy (breeding/resident)	316 km2
Number of locations	2-5	-
Severely fragmented?	no	-

	Estimate	Data quality	Derivation	Year of estimate
Population size	unknown	-	-	-
Population trend	decreasing	-	inferred	2016-2026
Rate of change over the past 10 years/3 generations (longer of the two periods)	1-10%	-	-	-
Rate of change over the future 10 years/3 generations (longer of the two periods)	1-10%	-	-	-
Rate of change over the past & future 10 years/3 generations (longer of the two periods)	1-10%	-	-	-
Generation length	2.9 years	-	-	-
Number of subpopulations	1	-	-	-
Percentage of mature individuals in largest subpopulation	100%	-	-	-

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

Trend justification: This species has a high forest dependency, and it is therefore inferred to be declining in line with ongoing forest loss on Moheli (Global Forest Watch 2021), likely for subsistence farmland and fuel wood (Sewall et al. 2003). Between 2001-2019, this species experienced forest cover loss of 6.6% (Global Forest Watch 2021). This would equate to 3.5% over 10 years. Between 2016-2019, this species experienced forest cover loss of 2.3% across its range (Global Forest Watch 2021). Projected forward 10 years from 2016, this would equate to a decline of 5.6%. The rate of decline is therefore suspected to fall in the band 1-10%.

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

Country/Territory	IBA Name
Comoros	Mont Mlédjélé (Mwali highlands)

Habitat (level 1)	Habitat (level 2)	Importance	Occurrence
Forest	Subtropical/Tropical Moist Lowland	major	resident
Altitude	500 - 0 m	Occasional altitudinal limits

Threat (level 1)	Threat (level 2)	Impact and Stresses
Agriculture & aquaculture	Annual & perennial non-timber crops - Small-holder farming	Timing		Scope		Severity		Impact
		Ongoing		Majority (50-90%)		Slow, Significant Declines		Medium Impact: 6
		Stresses Ecosystem conversion
Biological resource use	Logging & wood harvesting - Unintentional effects: (subsistence/small scale) [harvest]	Timing		Scope		Severity		Impact
		Ongoing		Majority (50-90%)		Slow, Significant Declines		Medium Impact: 6
		Stresses Species disturbance, Ecosystem degradation, Ecosystem conversion

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Recommended citation
BirdLife International (2024) Species factsheet: Moheli Brush-warbler Nesillas mariae. Downloaded from https://datazone.birdlife.org/species/factsheet/moheli-brush-warbler-nesillas-mariae on 28/12/2024.
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 28/12/2024.