CR
Principe Thrush Turdus xanthorhynchus



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.
Melo, M.; Bowie, R.C.K.; Voelker, G.; Dallimer, M.; Collar, N.J.; Jones, P.J. 2010. Multiple lines of evidence support the recognition of a very rare bird species: the Principe Thrush. Journal of Zoology (London) 282(2): 120-129.

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

Red List history
Year Category Criteria
2021 Critically Endangered B1ab(ii,iii,v); C2a(ii)
2018 Critically Endangered B1ab(ii,iii,v); C2a(ii)
2016 Critically Endangered B1ab(ii,iii,v); C2a(ii)
2015 Critically Endangered B1ab(ii,iii,v); C2a(ii)
2013 Critically Endangered B1ab(ii,iii,v); C2a(ii)
2012 Critically Endangered B1ab(ii,iii,v);C2a(ii)
2011 Critically Endangered B1a+b(ii,iii,v); C2a(ii)
2008 Not Recognised
2004 Not Recognised
2000 Not Recognised
1994 Not Recognised
1988 Not Recognised
Species attributes

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

Estimate Data quality
Extent of Occurrence (breeding/resident) 60 km2 good
Number of locations 1 -
Severely fragmented? no -
Population
Estimate Data quality Derivation Year of estimate
Population size 50-249 mature individuals good estimated 2010
Population trend decreasing poor inferred -
Generation length 3.4 years - - -
Number of subpopulations 1 - - -
Percentage of mature individuals in largest subpopulation 100% - - -

Population justification: Data collected during a survey of Príncipe in 2007 were used to derive a population estimate of 364 individuals (with a 95% confidence interval of 186-887) (Dallimer et al. 2010). However, the authors consider this to be an overestimate because the species does not occupy all areas of primary forest and the data may have been biased by the species's confiding nature and habit of readily approaching humans. Thus, it is estimated that there are fewer than 250 mature individuals (Dallimer et al. 2010), although more surveys are required.

Trend justification: The population is inferred to be in decline due to predation from introduced mammals, hunting, and habitat degradation. However, the rate of decline has not been estimated.


Country/territory distribution
Country/Territory Presence Origin Resident Breeding visitor Non-breeding visitor Passage migrant
São Tomé e Príncipe extant native yes

Important Bird and Biodiversity Areas (IBA)
Country/Territory IBA Name
São Tomé e Príncipe Príncipe forests

Habitats & altitude
Habitat (level 1) Habitat (level 2) Importance Occurrence
Forest Subtropical/Tropical Moist Lowland major resident
Forest Subtropical/Tropical Moist Montane major resident
Altitude 400 - 800 m Occasional altitudinal limits (min) 0 m

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 Minority (<50%) Slow, Significant Declines Low Impact: 5
Stresses
Ecosystem degradation, Ecosystem conversion
Biological resource use Hunting & trapping terrestrial animals - Intentional use (species is the target) Timing Scope Severity Impact
Ongoing Majority (50-90%) Unknown Unknown
Stresses
Species mortality
Biological resource use Logging & wood harvesting - Unintentional effects: (subsistence/small scale) [harvest] Timing Scope Severity Impact
Ongoing Minority (<50%) Slow, Significant Declines Low Impact: 5
Stresses
Ecosystem degradation, Ecosystem conversion
Invasive and other problematic species, genes & diseases Invasive non-native/alien species/diseases - Cercopithecus mona Timing Scope Severity Impact
Ongoing Majority (50-90%) Slow, Significant Declines Medium Impact: 6
Stresses
Species disturbance, Reduced reproductive success, Species mortality
Invasive and other problematic species, genes & diseases Invasive non-native/alien species/diseases - Civettictis civetta Timing Scope Severity Impact
Ongoing Majority (50-90%) Slow, Significant Declines Medium Impact: 6
Stresses
Species disturbance, Reduced reproductive success, Species mortality
Invasive and other problematic species, genes & diseases Invasive non-native/alien species/diseases - Felis catus Timing Scope Severity Impact
Ongoing Majority (50-90%) Slow, Significant Declines Medium Impact: 6
Stresses
Species disturbance, 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%) Slow, Significant Declines Medium Impact: 6
Stresses
Species disturbance, Reduced reproductive success, Species mortality
Residential & commercial development Tourism & recreation areas Timing Scope Severity Impact
Ongoing Majority (50-90%) Unknown Unknown
Stresses
Ecosystem degradation, Ecosystem conversion

Recommended citation
BirdLife International (2024) Species factsheet: Principe Thrush Turdus xanthorhynchus. Downloaded from https://datazone.birdlife.org/species/factsheet/principe-thrush-turdus-xanthorhynchus on 24/11/2024.
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 24/11/2024.