VU
Izu Thrush Turdus celaenops



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
- - A2ce+3ce+4ce; C1

Red List history
Year Category Criteria
2018 Vulnerable A2ce+3ce+4ce; C1
2016 Vulnerable A2ce+3ce+4ce;C1
2012 Vulnerable A2ce+3ce+4ce;C1
2008 Vulnerable A2c,e; A3c,e; A4c,e; C1
2004 Vulnerable
2000 Vulnerable
1996 Vulnerable
1994 Vulnerable
1988 Lower Risk/Least Concern
Species attributes

Migratory status not a migrant Forest dependency high
Land-mass type shelf island
Average mass 84 g
Range

Estimate Data quality
Extent of Occurrence (breeding/resident) 256,000 km2 medium
Extent of Occurrence (non-breeding) 271,000 km2 medium
Number of locations 11-100 -
Severely fragmented? no -
Population
Estimate Data quality Derivation Year of estimate
Population size 2500-9999 mature individuals medium estimated 2000
Population trend decreasing poor estimated 1998-2008
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 6.1 years - - -
Number of subpopulations 2-100 - - -

Population justification: The global population is estimated to be in the band c.2,500-9,999 mature individuals (BirdLife International 2001), equivalent to 3,750-14,999 individuals, rounded here to 3,500-15,000 individuals. The population in Japan has been estimated at c.100-10,000 breeding pairs (Brazil 2009).

Trend justification: On islands affected most heavily by introduced predators, population declines have been rapid; for example surveys on Miyake-jima showed declines from 24.4, 23.4 and 33.3 individuals per km in 1978-1980, to 6.7 and 11.1 individuals per km in 1990-1991. These results suggest a rapid decline is likely to be occurring across the population.


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

Important Bird and Biodiversity Areas (IBA)
Country/Territory IBA Name
Japan Oshima island
Japan Toshima island
Japan Niijima and Shikinejima Islands
Japan Kozushima island
Japan Miyakejima island
Japan Mikurajima island
Japan Hachijojima island
Japan Aogashima island
Japan Tokara islands

Habitats & altitude
Habitat (level 1) Habitat (level 2) Importance Occurrence
Artificial/Terrestrial Arable Land suitable non-breeding
Artificial/Terrestrial Rural Gardens suitable non-breeding
Forest Temperate major resident
Altitude   Occasional altitudinal limits  

Threats & impact
Threat (level 1) Threat (level 2) Impact and Stresses
Agriculture & aquaculture Wood & pulp plantations - Agro-industry plantations Timing Scope Severity Impact
Ongoing Minority (<50%) Slow, Significant Declines Low Impact: 5
Stresses
Ecosystem degradation, Ecosystem conversion
Geological events Volcanoes Timing Scope Severity Impact
Ongoing Majority (50-90%) Rapid Declines Medium Impact: 7
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 Minority (<50%) Rapid Declines Medium Impact: 6
Stresses
Reduced reproductive success, Species mortality
Invasive and other problematic species, genes & diseases Invasive non-native/alien species/diseases - Mustela sibirica Timing Scope Severity Impact
Ongoing Majority (50-90%) Rapid Declines Medium Impact: 7
Stresses
Reduced reproductive success, Species mortality
Invasive and other problematic species, genes & diseases Problematic native species/diseases - Corvus macrorhynchos_old Timing Scope Severity Impact
Ongoing Majority (50-90%) Rapid Declines Medium Impact: 7
Stresses
Reduced reproductive success, Species mortality
Residential & commercial development Tourism & recreation areas Timing Scope Severity Impact
Ongoing Minority (<50%) Slow, Significant Declines Low Impact: 5
Stresses
Ecosystem degradation, Ecosystem conversion
Transportation & service corridors Roads & railroads 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: Turdus celaenops. Downloaded from https://datazone.birdlife.org/species/factsheet/izu-thrush-turdus-celaenops on 19/03/2024.
Recommended citation for factsheets for more than one species: BirdLife International (2024) IUCN Red List for birds. Downloaded from https://datazone.birdlife.org on 19/03/2024.