VU
Green Warbler-finch Certhidea olivacea



Taxonomy

Taxonomic note

Certhidea olivacea and C. fusca (del Hoyo and Collar 2016) were previously lumped as C. olivacea following SACC (2005 & updates); Sibley & Monroe (1990, 1993).

 

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.

IUCN Red list criteria met and history
Red List criteria met
Critically Endangered Endangered Vulnerable
- - A2bce+3bce+4bce; B1ab(iii,v)

Red List history
Year Category Criteria
2017 Vulnerable A2bce+3bce+4bce; B1ab(iii,v)
2016 Least Concern
Species attributes

Migratory status not a migrant Forest dependency Low
Land mass type Average mass -
Distribution

Estimate Data quality
Extent of Occurrence breeding/resident (km2) 15,600 medium
Number of locations 6-10 -
Severely Fragmented -
Population and trend
Value Data quality Derivation Year of estimate
No. of mature individuals unknown not applicable not applicable 0
Population trend Decreasing estimated -
Decline (3 years/1 generation past) - - -
Decline (5 years/1 generation past) - - -
Decline (10 years/1 generation past) - - -
Decline (10 years/3 generation future) 30-49 - - -
Decline (10 years/3 generation past and future) 30-49 - - -
Number of subpopulations - - -
Percentage in largest subpopulation - - -
Generation length (yrs) 3.8 - - -

Population justification: The species has been described as 'common and widespread' (Jaramillo and Christie 2017). Dvorak et al. (2012) estimated the number of singing males at 55,500 (37,300-80,600) on Santa Cruz alone.

Trend justification: Dvorak et al. (2012) compared measures of abundance (in terms of number of individuals sighted per point during point count observations) between 2008-2010 and 1997-1998. Combining the per point observations of this species for each time period and looking at an overall average for both 1997-1998 and 2008-2010 suggests that between the two survey periods (which roughly equates to 3 generations lengths [c.11.5 years]), C. olivacea potentially declined by c.46% on Santa Cruz. The threats which occur on this island also occur elsewhere throughout the species's range (e.g. anthropogenic habitat alteration and invasives) and so it may be inferred that the species is undergoing a rapid decline in the range of 30-49% over 3 generations.


Country/territory distribution
Country/Territory Occurrence status Presence Resident Breeding Non-breeding Passage
Ecuador N Extant Yes

Important Bird and Biodiversity Areas (IBA)
Country/Territory IBA Name
Ecuador Tierras altas de Isabela
Ecuador Tierras altas de Santiago
Ecuador Tierras altas de Santa Cruz
Ecuador Puerto Ayora
Ecuador Áreas costeras de Fernandina y del occidente de Isabela

Habitats & altitude
Habitat (level 1) Habitat (level 2) Importance Occurrence
Artificial/Terrestrial Arable Land marginal resident
Forest Subtropical/Tropical Dry suitable resident
Forest Subtropical/Tropical Moist Montane suitable resident
Shrubland Subtropical/Tropical Dry major resident
Altitude 0 - 800 m Occasional altitudinal limits  

Threats & impact
Threat (level 1) Threat (level 2) Impact and Stresses
Agriculture & aquaculture Annual & perennial non-timber crops - Scale Unknown/Unrecorded Timing Scope Severity Impact
Ongoing Minority (<50%) Slow, Significant Declines Low Impact: 5
Stresses
Ecosystem degradation, Ecosystem conversion
Biological resource use Gathering terrestrial plants - Persecution/control Timing Scope Severity Impact
Ongoing Minority (<50%) Unknown Unknown
Stresses
Other
Invasive and other problematic species, genes & diseases Invasive non-native/alien species/diseases - Philornis downsi 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 - Unspecified species Timing Scope Severity Impact
Ongoing Majority (50-90%) Slow, Significant Declines Medium Impact: 6
Stresses
Ecosystem degradation
Residential & commercial development Housing & urban areas Timing Scope Severity Impact
Ongoing Minority (<50%) Slow, Significant Declines Low Impact: 5
Stresses
Ecosystem degradation, Ecosystem conversion

Recommended citation
BirdLife International (2022) Species factsheet: Certhidea olivacea. Downloaded from http://www.birdlife.org on 05/12/2022. Recommended citation for factsheets for more than one species: BirdLife International (2022) IUCN Red List for birds. Downloaded from http://www.birdlife.org on 05/12/2022.