• 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
2020	Least Concern
2016	Near Threatened	A2c+3c+4c
2012	Near Threatened	A2c+3c+4c
2008	Near Threatened	A2c; A3c; A4c
2004	Near Threatened
2000	Lower Risk/Near Threatened
1994	Lower Risk/Near Threatened
1988	Near Threatened

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

	Estimate	Data quality
Extent of Occurrence (breeding/resident)	288,000 km2	medium
Severely fragmented?	no	-

	Estimate	Data quality	Derivation	Year of estimate
Population size	20000-49999 mature individuals	poor	suspected	2020
Population trend	decreasing	poor	inferred	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	2.26 years	-	-	-
Number of subpopulations	2-5	-	-	-
Percentage of mature individuals in largest subpopulation	1-89%	-	-	-

Population justification: No survey data is available. The species has been described as infrequent and difficult to see (R. Amorin in litt. 2020). Based on the recorded population density of a congener (Phylloscartes virescens: 1.14 individuals per km²; Thiollay 1986), the area of tree cover with over 30% canopy cover within the range in 2010 (94,000 km²; Global Forest Watch 2020) and assuming that only 40-60% of forest within the species's range is occupied, the population size is tentatively suspected to be in the range of 42,864-64,296 individuals, roughly equating to 28,576-42,864 mature individuals. The population size is here placed in the band 20,000-49,999 mature individuals. The species has a disjunct distribution, so is likely to have more than one subpopulation.

Trend justification: Approximately 4% of tree cover was lost between 2009 and 2019 within the species's range (Global Forest Watch 2020). A continuing decline in population size is inferred. The population size is suspected to have declined by 1-9% over the past ten years.

Over three years from 2017-2019, approximately 1.6% of tree cover within the species's range was lost over three years (Global Forest Watch 2020). If this rate were to continue across ten years, this would equate to a loss of 5% of tree cover. Hence, over the next ten years, the population size is suspected to undergo a reduction of 1-9%.

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

Country/Territory	IBA Name

Habitat (level 1)	Habitat (level 2)	Importance	Occurrence
Forest	Subtropical/Tropical Moist Montane	major	resident
Altitude	950 - 2150 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
Natural system modifications	Fire & fire suppression - Increase in fire frequency/intensity	Timing		Scope		Severity		Impact
		Ongoing		Minority (<50%)		Unknown		Unknown
		Stresses Species disturbance, Ecosystem degradation, Species mortality
Residential & commercial development	Tourism & recreation areas	Timing		Scope		Severity		Impact
		Ongoing		Minority (<50%)		Unknown		Unknown
		Stresses Ecosystem degradation, Ecosystem conversion

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Recommended citation
BirdLife International (2024) Species factsheet: Serra do Mar Tyrannulet Phylloscartes difficilis. Downloaded from https://datazone.birdlife.org/species/factsheet/serra-do-mar-tyrannulet-phylloscartes-difficilis 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.