• Summary
• Text account
• Data table and detailed info
• Distribution map
• Reference and further resources

Taxonomic note

Formicivora acutirostris (del Hoyo and Collar 2016) was previously listed as Stymphalornis acutirostris.

 

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
2019	Near Threatened	B2ab(ii,iii,iv,v)
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
1994	Not Recognised
1988	Not Recognised

Migratory status	not a migrant	Forest dependency	does not normally occur in forest
Land-mass type	continent	Average mass	-

	Estimate	Data quality
Extent of Occurrence (breeding/resident)	27,900 km2	medium
Area of Occupancy (breeding/resident)	100 km2
Number of locations	11-100	-
Severely fragmented?	no	-

	Estimate	Data quality	Derivation	Year of estimate
Population size	5000-9999 mature individuals	good	estimated	2013
Population trend	decreasing	poor	inferred	2006-2020
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	4.8 years	-	-	-
Number of subpopulations	9	-	-	-
Percentage of mature individuals in largest subpopulation	1-89%	-	-	-

Population justification: The species is locally fairly common. Its population size was previously estimated at 17,700 mature individuals (Reinert et al. 2007), but a more recent study estimated the population at 7,511 mature individuals, based on recorded population densities and estimated areas of a range of habitats (Bornschein 2013). The population size is therefore placed in the band 5,000 - 9,999 mature individuals.

Trend justification: A continuing decline in population size can be inferred from the estimated reduction in the area of occupied habitat (Bornschein 2013). A study of the area of habitat within the species’s range estimated that it had decreased by 9.5% between 1978-1980 and 2013, largely as a result of encroachment of invasive plant species (Bornschein 2013), which is equivalent to a reduction of approximately 4% across three generations (14.4 years).

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

Country/Territory	IBA Name
Brazil	Área de Proteção Ambiental de Guaratuba
Brazil	Baía da Babitonga
Brazil	Rio Guaraguaçu

Habitat (level 1)	Habitat (level 2)	Importance	Occurrence
Grassland	Subtropical/Tropical Seasonally Wet/Flooded	suitable	resident
Wetlands (inland)	Bogs, Marshes, Swamps, Fens, Peatlands	major	resident
Wetlands (inland)	Shrub Dominated Wetlands	suitable	resident
Altitude	0 - 5 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 degradation, Ecosystem conversion
Biological resource use	Gathering terrestrial plants - Unintentional effects (species is not the target)	Timing		Scope		Severity		Impact
		Ongoing		Minority (<50%)		Negligible declines		Low Impact: 4
		Stresses Ecosystem degradation
Climate change & severe weather	Habitat shifting & alteration	Timing		Scope		Severity		Impact
		Future		Whole (>90%)				Low Impact: 4
		Stresses Indirect ecosystem effects, Species disturbance, Ecosystem degradation
Climate change & severe weather	Other impacts	Timing		Scope		Severity		Impact
		Future		Whole (>90%)		Slow, Significant Declines		Low Impact: 5
		Stresses Ecosystem degradation
Energy production & mining	Mining & quarrying	Timing		Scope		Severity		Impact
		Ongoing		Majority (50-90%)		Slow, Significant Declines		Medium Impact: 6
		Stresses Ecosystem degradation, Ecosystem conversion
Human intrusions & disturbance	Recreational activities	Timing		Scope		Severity		Impact
		Ongoing		Minority (<50%)		Slow, Significant Declines		Low Impact: 5
		Stresses Species disturbance, Ecosystem degradation
Human intrusions & disturbance	Work & other activities	Timing		Scope		Severity		Impact
		Ongoing		Minority (<50%)		Slow, Significant Declines		Low Impact: 5
		Stresses Species disturbance, Ecosystem degradation
Invasive and other problematic species, genes & diseases	Invasive non-native/alien species/diseases - Hedychium coronarium	Timing		Scope		Severity		Impact
		Ongoing		Majority (50-90%)		Slow, Significant Declines		Medium Impact: 6
		Stresses Ecosystem degradation
Invasive and other problematic species, genes & diseases	Invasive non-native/alien species/diseases - Named species	Timing		Scope		Severity		Impact
		Ongoing		Majority (50-90%)		Slow, Significant Declines		Medium Impact: 6
		Stresses Ecosystem degradation
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 Ecosystem degradation
Pollution	Industrial & military effluents - Oil spills	Timing		Scope		Severity		Impact
		Past, Likely to Return		Minority (<50%)		Slow, Significant Declines		Past Impact
		Stresses Ecosystem degradation
Residential & commercial development	Commercial & industrial areas	Timing		Scope		Severity		Impact
		Ongoing		Minority (<50%)		Slow, Significant Declines		Low Impact: 5
		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

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Recommended citation
BirdLife International (2024) Species factsheet: Parana Antwren Formicivora acutirostris. Downloaded from https://datazone.birdlife.org/species/factsheet/parana-antwren-formicivora-acutirostris on 27/12/2024.
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 27/12/2024.