NT
Tristan Thrush Turdus eremita



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.

IUCN Red list criteria met and history
Red List criteria met
Critically Endangered Endangered Vulnerable
- - -

Red List history
Year Category Criteria
2016 Near Threatened B1ab(v); C2a(i)
2012 Near Threatened B1ab(v);C2a(i)
2008 Near Threatened B1a+b(v); C2a(i)
2004 Near Threatened
2000 Lower Risk/Near Threatened
1994 Lower Risk/Near Threatened
1988 Lower Risk/Least Concern
Species attributes

Migratory status not a migrant Forest dependency Does not normally occur in forest
Land mass type Average mass -
Distribution

Estimate Data quality
Extent of Occurrence breeding/resident (km2) 810 medium
Number of locations -
Severely Fragmented -
Population and trend
Value Data quality Derivation Year of estimate
No. of mature individuals 1500-7000 medium estimated 2007
Population trend Stable suspected -
Decline (3 years/1 generation past) - - -
Decline (5 years/1 generation past) - - -
Decline (10 years/1 generation past) - - -
Decline (10 years/3 generation future) - - -
Decline (10 years/3 generation past and future) - - -
Number of subpopulations - - -
Percentage in largest subpopulation 100 - - -
Generation length (yrs) 4.3 - - -

Population justification: In 1972-1974, island population sizes were estimated as follows (in pairs): Tristan 40-60; Inaccessible 100-500; Nightingale 300-500; Middle 20-40; and Stoltenhoff 10-20. In the 1980s, the Inaccessible population was revised to 850 pairs, and the total population for the group to 6,000 birds. More recently, the Tristan population has been estimated (very crudely, but conservatively) as at least several hundred birds (P. G. Ryan in litt. 2000). It is best placed in the band 2,500-9,999 individuals, equating to 1,667-6,666 mature individuals, rounded here to 1,500-7,000 mature individuals.

Trend justification: There is presently no serious threat to the species and no evidence of declines in either its population or range, thus the species's population is currently suspected to be stable.


Country/territory distribution
Country/Territory Occurrence status Presence Resident Breeding Non-breeding Passage
St Helena (to UK) N Extant Yes

Important Bird and Biodiversity Areas (IBA)
Country/Territory IBA Name
St Helena (to UK) Tristan Island
St Helena (to UK) Inaccessible Island
St Helena (to UK) Nightingale Island group

Habitats & altitude
Habitat (level 1) Habitat (level 2) Importance Occurrence
Artificial/Terrestrial Rural Gardens suitable resident
Grassland Temperate suitable resident
Marine Intertidal Rocky Shoreline suitable resident
Shrubland Temperate suitable resident
Altitude 300 - 0 m Occasional altitudinal limits  

Threats & impact
Threat (level 1) Threat (level 2) Impact and Stresses
Invasive and other problematic species, genes & diseases Invasive non-native/alien species/diseases - Rattus rattus Timing Scope Severity Impact
Ongoing Minority (<50%) Unknown Unknown
Stresses
Reduced reproductive success

Recommended citation
BirdLife International (2021) Species factsheet: Turdus eremita. Downloaded from http://www.birdlife.org on 16/10/2021. Recommended citation for factsheets for more than one species: BirdLife International (2021) IUCN Red List for birds. Downloaded from http://www.birdlife.org on 16/10/2021.