• 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
-	B1ab(iii)+2ab(iii); D	B1ab(iii)+2ab(iii); D1

Red List history

Year	Category	Criteria
2020	Endangered	B1ab(iii)+2ab(iii)
2016	Endangered	B1ab(i,ii,iii,v)
2012	Endangered	B1ab(i,ii,iii,v)
2008	Endangered	B1a+b(i,ii,iii,v)
2004	Endangered
2000	Endangered
1996	Critically Endangered
1994	Critically Endangered
1988	Threatened

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

	Estimate	Data quality
Extent of Occurrence (breeding/resident)	410 km2	medium
Area of Occupancy (breeding/resident)	10 km2
Number of locations	2-5	-
Severely fragmented?	no	-

	Estimate	Data quality	Derivation	Year of estimate
Population size	50-8500 mature individuals	poor	suspected	2020
Population trend	decreasing	poor	suspected	2017-2027
Rate of change over the past 10 years/3 generations (longer of the two periods)	1-4%	-	-	-
Rate of change over the future 10 years/3 generations (longer of the two periods)	1-8%	-	-	-
Rate of change over the past & future 10 years/3 generations (longer of the two periods)	1-8%	-	-	-
Generation length	3.23 years	-	-	-
Number of subpopulations	1-7	-	-	-
Percentage of mature individuals in largest subpopulation	90-100%	-	-	-

Population justification: This species has an extremely small range, and it has been reported to be difficult to locate (Tobias et al. 1993, Tobias and Williams 1996), although it is considered locally abundant in suitable habitat (CEMAVE 2018). Reported densities are 156 pairs/km² at Vale do Mambucaba and 89 pairs/km² at Ariró (Gonzaga 2008), which collectively are thought to hold more than 90% of the total population (CEMAVE 2018). Although the population size has not been directly quantified, it is suspected to be smaller than 250 mature individuals, based on sightings by researchers within the range (CEMAVE 2018).

Based on an assumed minimum population density of 40 individuals/km² (consistent with status as a locally common antwren), an upper density of 267 individuals/km² (assumed equivalent to 89 pairs/km²), and assuming 11-45% of the mapped range is occupied, the population is here suspected to number 475-12,680 individuals . This equates to approximately 317-8,453 mature individuals, here rounded to 300-8,500 mature individuals. The population size is therefore placed in the band 50-8,500 mature individuals.

The number of subpopulations is not known. Based on discontinuities between areas with records, the species is assumed to have at least two subpopulations. According to the Brazilian national Red List, 90-100% of individuals are thought to comprise a single subpopulation (CEMAVE 2018). The largest subpopulation is therefore suspected to hold 45-8,500 mature individuals.

Trend justification: An ongoing slow population decline is suspected to be taking place, based on observational information (Tobias and Williams 1996) and remote-sensed data (Global Forest Watch 2020) on habitat loss. From 2010 to 2019, approximately 4% of tree cover was lost within the species's range (Global Forest Watch 2020). The species is tolerant of degraded habitat and occurs in scrubby habitats and secondary forest, so there is a low level of confidence in the population trend, but the species is suspected to be declining, with a suspected population reduction over the last ten years of 1-4%. In 2017, approximately 0.8% of forest within the species's range was lost within a single year (Global Forest Watch 2020). Extrapolating this rate over 10 years would equate to approximately 8%. Using this value as a maximum, the population is suspected to decline by 1-8% over the next decade.

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

Country/Territory	IBA Name
Brazil	Serra da Bocaina / Paraty / Angra dos Reis

Habitat (level 1)	Habitat (level 2)	Importance	Occurrence
Artificial/Terrestrial	Plantations	suitable	resident
Artificial/Terrestrial	Subtropical/Tropical Heavily Degraded Former Forest	suitable	resident
Shrubland	Subtropical/Tropical Dry	suitable	resident
Shrubland	Subtropical/Tropical Moist	major	resident
Altitude	0 - 50 m	Occasional altitudinal limits

Threat (level 1)	Threat (level 2)	Impact and Stresses
Agriculture & aquaculture	Livestock farming & ranching - Agro-industry grazing, ranching or farming	Timing		Scope		Severity		Impact
		Ongoing		Majority (50-90%)		Slow, Significant Declines		Medium Impact: 6
		Stresses Ecosystem degradation, Ecosystem conversion
Agriculture & aquaculture	Wood & pulp plantations - Agro-industry plantations	Timing		Scope		Severity		Impact
		Ongoing		Majority (50-90%)		Slow, Significant Declines		Medium Impact: 6
		Stresses Ecosystem degradation, Ecosystem conversion
Residential & commercial development	Housing & urban areas	Timing		Scope		Severity		Impact
		Ongoing		Majority (50-90%)		Slow, Significant Declines		Medium Impact: 6
		Stresses Ecosystem degradation, Ecosystem conversion
Residential & commercial development	Tourism & recreation areas	Timing		Scope		Severity		Impact
		Ongoing		Majority (50-90%)		Slow, Significant Declines		Medium Impact: 6
		Stresses Ecosystem degradation, Ecosystem conversion

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Recommended citation
BirdLife International (2024) Species factsheet: Black-hooded Antwren Formicivora erythronotos. Downloaded from https://datazone.birdlife.org/species/factsheet/black-hooded-antwren-formicivora-erythronotos on 23/12/2024.
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 23/12/2024.