CR
Medium Tree-finch Geospiza pauper



Taxonomy

Taxonomic note

Geospiza pauper (del Hoyo and Collar 2016) was previously placed in the genus Camarhynchus following SACC (2005 & updates); Sibley & Monroe (1990, 1993); Stotz et al. (1996).

 

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: #http://www.museum.lsu.edu/~Remsen/SACCBaseline.htm#.

IUCN Red List criteria met and history
Red List criteria met
Critically Endangered Endangered Vulnerable
B1ab(v) B1ab(v)+2ab(v); C2a(ii) B1ab(v)+2ab(v); C2a(i,ii); D1+2

Red List history
Year Category Criteria
2018 Critically Endangered B1ab(v)
2016 Critically Endangered B1ab(v)
2015 Critically Endangered B1ab(v)
2013 Critically Endangered B1ab(v)
2012 Critically Endangered B1ab(v)
2010 Critically Endangered B1a+b(v)
2009 Critically Endangered B1a+b(v)
2008 Vulnerable
2004 Vulnerable
2000 Vulnerable
1994 Lower Risk/Near Threatened
1988 Threatened
Species attributes

Migratory status not a migrant Forest dependency medium
Land-mass type Average mass -
Range

Estimate Data quality
Extent of Occurrence (breeding/resident) 30 km2 medium
Area of Occupancy (breeding/resident) 23 km2 good
Number of locations 1 -
Severely fragmented? no -
Population
Estimate Data quality Derivation Year of estimate
Population size 600-1700 mature individuals good estimated 2008
Population trend decreasing medium estimated 1999-2010
Generation length 3.8 years - - -
Number of subpopulations 1 - - -
Percentage of mature individuals in largest subpopulation 100% - - -

Population justification: The maximum size of the population was estimated at 1,660 individuals in 2008. It is best placed in the band 1,000-2,499 individuals, equating to 667-1,666 mature individuals, rounded here to 600-1,700 mature individuals.

Trend justification: Numbers in 2008 were 39% of those recorded in 2004, indicating a decline outside the range expected for a fluctuating but stable population. Density fell from 154 birds/km2 in 2004 to 60 birds/km2 in 2008 at Cerro Pajas, and it is significantly less common now than it was 50 to 100 years ago (O'Connor et al. 2010a).


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

Important Bird and Biodiversity Areas (IBA)
Country/Territory IBA Name
Ecuador Isla Floreana

Habitats & altitude
Habitat (level 1) Habitat (level 2) Importance Occurrence
Forest Subtropical/Tropical Dry major resident
Forest Subtropical/Tropical Moist Montane major resident
Shrubland Subtropical/Tropical Moist major resident
Altitude 0 - 640 m Occasional altitudinal limits  

Threats & impact
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%) Unknown Unknown
Stresses
Ecosystem degradation, Ecosystem conversion
Climate change & severe weather Habitat shifting & alteration Timing Scope Severity Impact
Future Whole (>90%) Unknown Unknown
Stresses
Indirect ecosystem effects, Ecosystem degradation
Invasive and other problematic species, genes & diseases Invasive non-native/alien species/diseases - Bos taurus Timing Scope Severity Impact
Ongoing Majority (50-90%) Unknown Unknown
Stresses
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 - Equus asinus Timing Scope Severity Impact
Ongoing Majority (50-90%) Unknown Unknown
Stresses
Ecosystem degradation
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
Invasive and other problematic species, genes & diseases Invasive non-native/alien species/diseases - Philornis downsi Timing Scope Severity Impact
Ongoing Majority (50-90%) Rapid Declines Medium Impact: 7
Stresses
Reduced reproductive success, Species mortality
Invasive and other problematic species, genes & diseases Invasive non-native/alien species/diseases - Rattus rattus Timing Scope Severity Impact
Ongoing Majority (50-90%) Unknown Unknown
Stresses
Reduced reproductive success, Species mortality
Invasive and other problematic species, genes & diseases Invasive non-native/alien species/diseases - Sus domesticus Timing Scope Severity Impact
Ongoing Majority (50-90%) Unknown Unknown
Stresses
Ecosystem degradation
Invasive and other problematic species, genes & diseases Problematic native species/diseases - Geospiza parvula Timing Scope Severity Impact
Ongoing Whole (>90%) Unknown Unknown
Stresses
Hybridisation
Invasive and other problematic species, genes & diseases Problematic native species/diseases - Geospiza psittacula Timing Scope Severity Impact
Ongoing Whole (>90%) Unknown Unknown
Stresses
Hybridisation
Invasive and other problematic species, genes & diseases Viral/prion-induced diseases - Avipoxvirus Timing Scope Severity Impact
Ongoing Majority (50-90%) Rapid Declines Medium Impact: 7
Stresses
Reduced reproductive success, Species mortality

Recommended citation
BirdLife International (2024) Species factsheet: Geospiza pauper. Downloaded from https://datazone.birdlife.org/species/factsheet/medium-tree-finch-geospiza-pauper on 19/03/2024.
Recommended citation for factsheets for more than one species: BirdLife International (2024) IUCN Red List for birds. Downloaded from https://datazone.birdlife.org on 19/03/2024.