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
2012 Not Recognised
2008 Not Recognised
2004 Not Recognised
2000 Not Recognised
1994 Not Recognised
1988 Not Recognised
Species attributes

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

Estimate Data quality
Extent of Occurrence (breeding/resident) 15,600 km2 medium
Number of locations 6-10 -
Severely fragmented? no -
Population
Estimate Data quality Derivation Year of estimate
Population size unknown - - -
Population trend decreasing - estimated 2011-2022
Rate of change over the past 10 years/3 generations (longer of the two periods) 30-49% - - -
Rate of change over the future 10 years/3 generations (longer of the two periods) 30-49% - - -
Rate of change over the past & future 10 years/3 generations (longer of the two periods) 30-49% - - -
Generation length 3.8 years - - -

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 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 Áreas costeras de Fernandina y del occidente de Isabela
Ecuador Puerto Ayora
Ecuador Tierras altas de Isabela
Ecuador Tierras altas de Santa Cruz
Ecuador Tierras altas de Santiago

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 (2024) Species factsheet: Green Warbler-finch Certhidea olivacea. Downloaded from https://datazone.birdlife.org/species/factsheet/green-warbler-finch-certhidea-olivacea 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.