NT
Slender-billed Finch Xenospingus concolor



Taxonomy

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.

IUCN Red List criteria met and history
Red List criteria met
Critically Endangered Endangered Vulnerable
- C2a(ii) C2a(i,ii)

Red List history
Year Category Criteria
2021 Near Threatened C2a(ii)
2016 Near Threatened C2a(i)
2012 Near Threatened C2a(i)
2008 Near Threatened C2a(i)
2004 Near Threatened
2000 Vulnerable
1996 Vulnerable
1994 Vulnerable
1988 Threatened
Species attributes

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

Estimate Data quality
Extent of Occurrence (breeding/resident) 303,000 km2 medium
Severely fragmented? no -
Population
Estimate Data quality Derivation Year of estimate
Population size 1000-2499 mature individuals poor inferred 2021
Population trend decreasing poor inferred 2015-2025
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 2.8 years - - -
Number of subpopulations 1 - - -
Percentage of mature individuals in largest subpopulation 100% - - -

Population justification: The global population size has not been quantified. The national population in Peru is estimated at less than 1,000 individuals (SERFOR 2018); assuming that around 2/3 of the population are mature this equates to roughly 670 mature individuals. There are no population size estimates available for Chile. The species appears local and less common in Peru, but fairly common in Chile (Jaramillo 2020). Based on this, and on observational records from eBird (2021), the national population in Chile may at most be twice the size of the population in Peru and is therefore tentatively suspected to number up to 2,000 mature individuals, roughly equating to 1,330 mature individuals. This number however requires confirmation. Based on these values, the global population is preliminarily inferred to number up to 2,000 mature individuals. To account for uncertainty, it is here placed in the band 1,000-2,499 mature individuals.
The subpopulation structure has not been formally assessed. However, it is assumed that the northern part of the distribution range acts as a population sink with individuals from southern Peru and Chile moving into the area (SERFOR 2018). Based on this, the population is assessed as forming one subpopulation.

Trend justification: Population trends differ across the range. The population is declining particularly in Peru, where the species has become rare and local owing to habitat loss and degradation (SERFOR 2018; Jaramillo 2020). The conversion of riparian thickets and shrubs to agricultural fields and settlements make the zone unsuitable for the species, as it does not occur in open or ubranised areas (Jaramillo 2020). This decline is partly alleviated by local increases and a range expansion in Chile (Jaramillo 2020). Precautionarily the overall population is inferred to be in decline as its habitat, and with it the Area of Occupancy, are shrinking in the north of the range. The rate of decline has not been quantified, but is unlikely to exceed 10% over ten years.


Country/territory distribution
Country/Territory Presence Origin Resident Breeding visitor Non-breeding visitor Passage migrant
Chile extant native yes
Peru extant native yes

Important Bird and Biodiversity Areas (IBA)
Country/Territory IBA Name
Chile Valle Azapa
Chile Valle de Chaca
Chile Valle de Lluta
Peru Atiquipa
Peru Cotahuasi
Peru Nazca
Peru Pisco
Peru Río Tambo y Lagunas de Mejía
Peru Valle del Majes

Habitats & altitude
Habitat (level 1) Habitat (level 2) Importance Occurrence
Artificial/Terrestrial Rural Gardens suitable resident
Shrubland Subtropical/Tropical Dry major resident
Shrubland Subtropical/Tropical Moist major resident
Wetlands (inland) Permanent Rivers/Streams/Creeks (includes waterfalls) major resident
Altitude 0 - 500 m Occasional altitudinal limits (max) 3500 m

Threats & impact
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%) Rapid Declines Medium Impact: 6
Stresses
Ecosystem degradation, Ecosystem conversion
Agriculture & aquaculture Annual & perennial non-timber crops - Small-holder farming 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 Majority (50-90%) Slow, Significant Declines Medium Impact: 6
Stresses
Ecosystem degradation

Recommended citation
BirdLife International (2024) Species factsheet: Slender-billed Finch Xenospingus concolor. Downloaded from https://datazone.birdlife.org/species/factsheet/slender-billed-finch-xenospingus-concolor on 24/12/2024.
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 24/12/2024.