EN
Juan Fernandez Tit-tyrant Anairetes fernandezianus



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

IUCN Red List criteria met and history
Red List criteria met
Critically Endangered Endangered Vulnerable
- C2a(i,ii) A2be+4be; C2a(i,ii); D1

Red List history
Year Category Criteria
2023 Endangered C2a(ii)
2016 Near Threatened D2
2012 Near Threatened D2
2008 Near Threatened D2
2004 Near Threatened
2000 Lower Risk/Near Threatened
1994 Lower Risk/Least Concern
1988 Lower Risk/Least Concern
Species attributes

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

Estimate Data quality
Extent of Occurrence (breeding/resident) 136 km2 medium
Area of Occupancy (breeding/resident) 136 km2
Number of locations 11-100 -
Severely fragmented? no -
Population
Estimate Data quality Derivation Year of estimate
Population size 250-1550, 520 mature individuals good estimated 2023
Population trend decreasing poor inferred 2019-2029
Rate of change over the past 10 years/3 generations (longer of the two periods) 39% - - -
Rate of change over the past & future 10 years/3 generations (longer of the two periods) 30-39% - - -
Generation length 2.51 years - - -
Number of subpopulations 1 - - -
Percentage of mature individuals in largest subpopulation 100% - - -

Population justification: Estimated at 5,000 individuals during the mid-1980s (Brooke 1987), the population appears to have undergone a rapid decline since. While census data suggested a population of 4,200 individuals in 1994, it declined to 2,000 individuals in 2001 and to 1,550 individuals in 2009 (Hahn et al. 2011). Under the assumption that declines are continuing at this rate to the present day, the current population is thought to number 780 individuals, which equates to 520 mature individuals.
The population size is here placed in the band 250-1,550 mature individuals, with a best estimate of 520 mature individuals. This wide band reflects the uncertainty in the current estimate and the absence of recent population and trend data; the minimum population size is set as 250 mature individuals under the assumption that declines may have accelerated, while the maximum is set as 1,550 mature individuals under the assumption that the population has remained stable since 2009.

Trend justification: In the mid-1980s the population was estimated to be stable and secure at 5,000 individuals (Brooke 1987). Since then, the species however appears to have suffered from habitat loss through land-use change and the spread of invasive plants, as well as from predation by birds and introduced mammals (Hahn et al. 2011). While the population numbered around 4,200 individuals in 1994, it dropped to 2,000 individuals in 2001 and further to 1,550 in 2009 following an exponential decline (Hahn et al. 2011).
There is no recent data on the population trend. However, under the assumption that the population continued to decline exponentially to the present day, the rate of decline amounts to 39% over the past ten years.
There are currently considerable efforts being undertaken to restore native vegetation and to eradicate introduced predators (Dittrich 2019); this may prove beneficial to the species and it is therefore likely that the rate of decline will slow down in the near future. Precautionarily, it is however inferred that population declines will go on at a similar rate into the near future, here placed in the band 30-39% over ten years.


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

Important Bird and Biodiversity Areas (IBA)
Country/Territory IBA Name
Chile Parque Nacional Archipiélago de Juan Fernández: Islas Robinson Crusoe and Santa Clara

Habitats & altitude
Habitat (level 1) Habitat (level 2) Importance Occurrence
Artificial/Terrestrial Rural Gardens suitable resident
Forest Subtropical/Tropical Dry major resident
Shrubland Subtropical/Tropical Dry major resident
Altitude 0 - 900 m Occasional altitudinal limits  

Threats & impact
Threat (level 1) Threat (level 2) Impact and Stresses
Biological resource use Logging & wood harvesting - Unintentional effects: (subsistence/small scale) [harvest] Timing Scope Severity Impact
Past, Unlikely to Return Majority (50-90%) Rapid Declines Past Impact
Stresses
Ecosystem degradation, Ecosystem conversion
Invasive and other problematic species, genes & diseases Invasive non-native/alien species/diseases - Felis catus Timing Scope Severity Impact
Ongoing Majority (50-90%) Rapid Declines Medium Impact: 7
Stresses
Species mortality
Invasive and other problematic species, genes & diseases Invasive non-native/alien species/diseases - Geranoaetus polyosoma Timing Scope Severity Impact
Ongoing Majority (50-90%) Rapid Declines Medium Impact: 7
Stresses
Species mortality
Invasive and other problematic species, genes & diseases Invasive non-native/alien species/diseases - Named species Timing Scope Severity Impact
Ongoing Majority (50-90%) Rapid Declines Medium Impact: 7
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%) Rapid Declines Medium Impact: 7
Stresses
Ecosystem degradation, Ecosystem conversion

Recommended citation
BirdLife International (2024) Species factsheet: Anairetes fernandezianus. Downloaded from https://datazone.birdlife.org/species/factsheet/juan-fernandez-tit-tyrant-anairetes-fernandezianus on 02/03/2024.
Recommended citation for factsheets for more than one species: BirdLife International (2024) IUCN Red List for birds. Downloaded from https://datazone.birdlife.org on 02/03/2024.