• 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.
SACC. 2005 and updates. A classification of the bird species of South America. Available at: https://www.museum.lsu.edu/~Remsen/SACCBaseline.htm.

Red List criteria met

Critically Endangered	Endangered	Vulnerable
-	-	-

Red List history

Year	Category	Criteria
2023	Least Concern
2016	Near Threatened	A2c+3c+4c;B1ab(i,ii,iii,v);C2a(i)
2012	Near Threatened	A2c+3c+4c;B1ab(i,ii,iii,v);C2a(i)
2008	Near Threatened	A2c; A3c; A4c; B1a+b(i,ii,iii,v); C2a(i)
2004	Near Threatened
2000	Vulnerable
1996	Vulnerable
1994	Vulnerable
1988	Threatened

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

	Estimate	Data quality
Extent of Occurrence (breeding/resident)	286,500 km2	medium
Severely fragmented?	no	-

	Estimate	Data quality	Derivation	Year of estimate
Population size	unknown	-	-	-
Population trend	decreasing	poor	suspected	2017-2027
Rate of change over the past 10 years/3 generations (longer of the two periods)	1-9%	-	-	-
Rate of change over the future 10 years/3 generations (longer of the two periods)	1-9%	-	-	-
Rate of change over the past & future 10 years/3 generations (longer of the two periods)	1-9%	-	-	-
Generation length	2.84 years	-	-	-
Number of subpopulations	2-100	-	-	-

Population justification: The global population size has not been quantified, but this species is described as common and relatively abundant (CSS Brazil and CEMAVE-ICMBio 2020).

Trend justification: There are no recent data on the population size or trend. However, ongoing declines are suspected, owing to rates of habitat destruction and degradation within the species' range.
Over ten years, 8% of tree cover is lost within the range (Global Forest Watch 2022, using Hansen et al. [2013] data and methods disclosed therein). The species is able to tolerate some degree of habitat conversion and is also found in small forest patches (CSS Brazil and CEMAVE-ICMBio 2020). Therefore, any population declines are unlikely to be rapid. Tentatively, population declines are here placed in the band 1-9% over ten years, but an exact quantification is urgently required.

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

Country/Territory	IBA Name
Brazil	Boa Nova / Serra da Ouricana
Brazil	Vitória da Conquista

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
Forest	Subtropical/Tropical Moist Montane	major	resident
Altitude	250 - 1060 m	Occasional altitudinal limits

Threat (level 1)	Threat (level 2)	Impact and Stresses
Agriculture & aquaculture	Annual & perennial non-timber crops - Agro-industry farming	Timing		Scope		Severity		Impact
		Ongoing		Minority (<50%)		Slow, Significant Declines		Low Impact: 5
		Stresses Ecosystem degradation, Ecosystem conversion
Agriculture & aquaculture	Livestock farming & ranching - Agro-industry grazing, ranching or farming	Timing		Scope		Severity		Impact
		Ongoing		Minority (<50%)		Slow, Significant Declines		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%)		Negligible declines		Low Impact: 4
		Stresses Ecosystem degradation
Energy production & mining	Mining & quarrying	Timing		Scope		Severity		Impact
		Ongoing		Minority (<50%)		Slow, Significant Declines		Low Impact: 5
		Stresses Ecosystem degradation, Ecosystem conversion

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Recommended citation
BirdLife International (2024) Species factsheet: Narrow-billed Antwren Formicivora iheringi. Downloaded from https://datazone.birdlife.org/species/factsheet/narrow-billed-antwren-formicivora-iheringi 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.