• 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	Near Threatened	A2cd+3cd+4cd
2016	Vulnerable	A2cd+3cd+4cd
2012	Vulnerable	A2cd+3cd+4cd
2008	Vulnerable	A2c,d; A3c,d; A4c,d
2004	Vulnerable
2000	Lower Risk/Near Threatened
1994	Lower Risk/Near Threatened
1988	Near Threatened

Migratory status	altitudinal migrant	Forest dependency	high
Land-mass type	continent	Average mass	-

	Estimate	Data quality
Extent of Occurrence (breeding/resident)	2,100,000 km2	medium
Severely fragmented?	no	-

	Estimate	Data quality	Derivation	Year of estimate
Population size	80000-130000 mature individuals	poor	suspected	2020
Population trend	decreasing	poor	inferred	2004-2021
Rate of change over the past 10 years/3 generations (longer of the two periods)	10-24%	-	-	-
Rate of change over the future 10 years/3 generations (longer of the two periods)	10-24%	-	-	-
Rate of change over the past & future 10 years/3 generations (longer of the two periods)	10-24%	-	-	-
Generation length	5.54 years	-	-	-

Population justification: It is locally common in Brazil (F. Olmos in litt. 2003) and Paraguay (especially in Canindeyú, San Pedro, and Amambay) (A. Bodrati in litt. 2007), but rare in many sites and rare in Argentina (Bodrati and Cockle 2006). In Argentina, there are suspected to be fewer than 250 mature individuals (MAyDS and Aves Argentinas 2017).

A survey using line transects and acoustic-based distance sampling in primary forest in Pico do Marumbi State Park, Parana, estimated 15 adult males per km² (95% CI 11.9-18.7; Oliveira 2012). Surveys in Irati National Forest found that the species was 2.6 times more abundant in natural Araucaria forest than in Araucaria plantations (Volpato et al. 2010). Surveys in and around Capão Bonito National Forest found that the species was 2.23 times more abundant in native forest than in planted forest, and 1.25 times more abundant in native forest than in agricultural areas (de Matos et al. 2018).

Based on the area of forest within the mapped range with at least 75% canopy cover in 2010 (c.345,000 km²; Global Forest Watch 2020), a population density of 35.7-56.1 individuals per km² (Oliveira 2012) and assuming 1% of the habitat is occupied, the population size is tentatively suspected to be in the range 123,165-193,545 individuals, roughly equating to 82,110-129,030 mature individuals and here placed in the band 80,000 - 130,000 mature individuals.

The subpopulation structure is not known.

Trend justification: It appears to have disappeared from some areas of interior semi deciduous Atlantic Forest, and declined in larger remnants, in São Paulo and Paraná states, Brazil (V. Cavarvere in litt. 2020). However, where a forest remnant has been protected and restored in Bahia, the species has recolonised over the past decade and become abundant, expanding its range into areas of secondary forest (K. M. Flesher in litt. 2017, 2018).

Over 17 years from 2002 to 2019, approximately 14% of tree cover with at least 50% canopy cover was lost from within the species's range (Global Forest Watch 2020). From this information, the species's population is inferred to be declining.

A comparison of the results of surveys carried out in 2005-2006 with those carried out 30 years earlier, in a semideciduous forest remnant in the state of São Paulo, found that the species's abundance had declined by 71% across 30 years, which is a rate equivalent to 50% over three generations (Cavarzere et al. 2012).

The species is threatened by trapping as well as by deforestation. It is assumed that trapping may have contributed an additional 10% decline. The species's population size is therefore assumed to have undergone a reduction of up to 24% over the past three generations (17 years), and is assumed to continue to decline at the same rate.

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

Country/Territory	IBA Name
Argentina	Parque Provincial Uruzú y Reserva Forestal San Jorge
Brazil	Estação Ecológica de Juréia-Itatins
Brazil	Região de Blumenau
Brazil	Reserva Biológica de Poço das Antas
Paraguay	Arroyo Blanco
Paraguay	Arroyo Tagatiya
Paraguay	Bosque Mbaracayú
Paraguay	Cerrados de Concepción
Paraguay	Cerro Guazú
Paraguay	Estancia Felicidad
Paraguay	Estancia Itabó
Paraguay	Estancia Sombrero
Paraguay	Ka'aguy Rory
Paraguay	Limoy
Paraguay	Morombi
Paraguay	Parque Nacional San Rafael
Paraguay	Paso Curuzú
Paraguay	Reserva Itabó - Itaipú
Paraguay	Serranías de San Joaquín
Paraguay	Ypané Medio
Paraguay	Ypeti

Habitat (level 1)	Habitat (level 2)	Importance	Occurrence
Forest	Subtropical/Tropical Moist Lowland	major	resident
Forest	Subtropical/Tropical Moist Montane	major	non-breeding
Altitude	0 - 1150 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		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
		Past, Unlikely to Return		Minority (<50%)		Slow, Significant Declines		Past Impact
		Stresses Ecosystem degradation, Ecosystem conversion
Biological resource use	Hunting & trapping terrestrial animals - Intentional use (species is the target)	Timing		Scope		Severity		Impact
		Ongoing		Majority (50-90%)		Slow, Significant Declines		Medium Impact: 6
		Stresses Species mortality
Biological resource use	Logging & wood harvesting - Unintentional effects: (subsistence/small scale) [harvest]	Timing		Scope		Severity		Impact
		Ongoing		Minority (<50%)		Slow, Significant Declines		Low Impact: 5
		Stresses Ecosystem degradation
Energy production & mining	Mining & quarrying	Timing		Scope		Severity		Impact
		Past, Unlikely to Return		Minority (<50%)		Rapid Declines		Past Impact
		Stresses Ecosystem conversion
Residential & commercial development	Commercial & industrial areas	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
Transportation & service corridors	Roads & railroads	Timing		Scope		Severity		Impact
		Ongoing		Majority (50-90%)		Slow, Significant Declines		Medium Impact: 6
		Stresses Ecosystem degradation, Ecosystem conversion

Purpose	Scale
Pets/display animals, horticulture	international

---

Recommended citation
BirdLife International (2024) Species factsheet: Bare-throated Bellbird Procnias nudicollis. Downloaded from https://datazone.birdlife.org/species/factsheet/bare-throated-bellbird-procnias-nudicollis on 22/11/2024.
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 22/11/2024.