• 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(ii,iii,v); C2a(i,ii); D	B1ab(ii,iii,v)+2ab(ii,iii,v); C2a(i,ii); D	B1ab(ii,iii,v)+2ab(ii,iii,v); C2a(i,ii); D1+2

Red List history

Year	Category	Criteria
2021	Critically Endangered	B1ab(ii,iii,v); C2a(i,ii); D
2018	Critically Endangered	B1ab(i,ii,iii,v);C2a(i,ii);D
2016	Critically Endangered	B1ab(i,ii,iii,v);C2a(i,ii);D
2013	Critically Endangered	B1ab(i,ii,iii,v);C2a(i,ii);D
2012	Critically Endangered	B1ab(i,ii,iii,v);C2a(i,ii);D
2010	Critically Endangered	B1a+b(i,ii,iii,v); C2a(ii)
2009	Critically Endangered	B1a+b(i,ii,iii,v); C2a(ii)
2008	Critically Endangered
2006	Critically Endangered
2005	Critically Endangered
2004	Critically Endangered
2000	Critically 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)	34 km2	medium
Area of Occupancy (breeding/resident)	56 km2
Number of locations	1	-
Severely fragmented?	no	-

	Estimate	Data quality	Derivation	Year of estimate
Population size	1-49 mature individuals	medium	estimated	2020
Population trend	decreasing	poor	inferred	2012-2022
Rate of change over the past 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	3.58 years	-	-	-
Number of subpopulations	1	-	-	-
Percentage of mature individuals in largest subpopulation	100%	-	-	-

Population justification: There have been very few recent records of the species. In the Jequitinhonha valley (the sole currently known population), at least four birds were found in a 100 ha area in the early 2000s, but it was thought unlikely that this density could be extrapolated for the whole 2,000 ha partly fragmented patch of forest (R. Ribon in litt. 2006, 2020). Subsequent surveys in the RPPN Mata do Passarinho and mata do Lodo found six individuals: five females and a single male (Damasceno 2011). Three males were recorded in 2012 (WikiAves 2013) and in 2011 the total population was considered to be no more than 10-15 individuals (R. Ribon in litt. 2011). Surveys in 2016 found only one pair with a nest, which failed, and surveys in 2017 did not detect any individuals (Rutter 2018). An expedition in 2018 found a single female outside the boundaries of the Reserva Mata do Passarinho (BirdGuides 2018). It is therefore now considered probable that there are no more than 10 individuals remaining (A. Souza in litt. 2020), and the population size is placed in the band 1-49 mature individuals.

Trend justification: There are no direct data on population trends. The species's population size is inferred to be in decline based on ongoing habitat degradation caused by fires and logging. According to Global Forest Watch, approximately 8.5% of tree cover with at least 50% canopy cover was lost within the species's mapped extant range over three generations (11 years) from 2008-2019 (Global Forest Watch 2020). This loss largely occurred in 2016 (Global Forest Watch 2020), when a large fire is known to have occurred (R. Ribon in litt. 2020). The species's population is therefore suspected to have declined by up to 10% over the past ten years.

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

Country/Territory	IBA Name
Brazil	Bandeira / Macarani

Habitat (level 1)	Habitat (level 2)	Importance	Occurrence
Artificial/Terrestrial	Subtropical/Tropical Heavily Degraded Former Forest	suitable	resident
Forest	Subtropical/Tropical Dry	major	resident
Altitude	0 - 930 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
		Past, Likely to Return		Majority (50-90%)		Slow, Significant Declines		Past Impact
		Stresses Ecosystem degradation, Ecosystem conversion
Agriculture & aquaculture	Livestock farming & ranching - Agro-industry grazing, ranching or farming	Timing		Scope		Severity		Impact
		Ongoing		Whole (>90%)		Slow, Significant Declines		Medium Impact: 7
		Stresses Species disturbance, Ecosystem degradation, Ecosystem conversion, Species mortality
Agriculture & aquaculture	Wood & pulp plantations - Agro-industry plantations	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		Whole (>90%)		Slow, Significant Declines		Medium Impact: 7
		Stresses Ecosystem degradation
Climate change & severe weather	Droughts	Timing		Scope		Severity		Impact
		Ongoing		Whole (>90%)		Unknown		Unknown
		Stresses Indirect ecosystem effects, Ecosystem degradation
Invasive and other problematic species, genes & diseases	Invasive non-native/alien species/diseases - Canis familiaris	Timing		Scope		Severity		Impact
		Ongoing		Majority (50-90%)		Unknown		Unknown
		Stresses Species mortality
Invasive and other problematic species, genes & diseases	Invasive non-native/alien species/diseases - Felis catus	Timing		Scope		Severity		Impact
		Ongoing		Majority (50-90%)		Unknown		Unknown
		Stresses Species mortality
Natural system modifications	Fire & fire suppression - Increase in fire frequency/intensity	Timing		Scope		Severity		Impact
		Ongoing		Majority (50-90%)		Slow, Significant Declines		Medium Impact: 6
		Stresses Species disturbance, Ecosystem degradation, Species mortality

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Recommended citation
BirdLife International (2024) Species factsheet: Stresemann's Bristlefront Merulaxis stresemanni. Downloaded from https://datazone.birdlife.org/species/factsheet/stresemanns-bristlefront-merulaxis-stresemanni 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.