Erithacus komadori 


Taxonomy [top]

Kingdom Phylum Class Order Family
Animalia Chordata Aves Passeriformes Muscicapidae

Scientific Name: Erithacus komadori
Species Authority: (Temminck, 1835)
Common Name(s):
English Ryukyu Robin

Assessment Information [top]

Red List Category & Criteria: Near Threatened ver 3.1
Year Published: 2012
Date Assessed: 2012-05-01
Assessor(s): BirdLife International
Reviewer(s): Butchart, S. & Symes, A.
Contributor(s): Chan, S.
Facilitator/Compiler(s): Benstead, P., Bird, J., Khwaja, N.
This species is thought to have a moderately small and declining range and consequently it is considered Near Threatened.

Previously published Red List assessments:
2008 Near Threatened (NT)
2004 Near Threatened (NT)
2000 Lower Risk/least concern (LR/lc)
1994 Lower Risk/near threatened (LR/nt)
1988 Near Threatened (NT)

Geographic Range [top]

Range Description: Erithacus komadori is the most abundant of the endemic birds restricted to the Nansei Shoto archipelago, Japan. Three subspecies are currently recognised: subspecies subrufa, which occurs on the islands of Ishigaki, Iriomote and Yonaguni (where it is poorly known and may be of doubtful validity); subspecies namiyei, which is endemic to the northern part of Okinawa Island, and subspecies komadori, which inhabits the southern islands of of Kagoshima and Okinawa. The population is considered to be around 80,000-90,000 individuals (S. Chan in litt. 2003). It remains common on Amami-oshima, Toku-noshima and the northern part of Okinawa, but steep declines have been reported from some islands.

Countries occurrence:
Continuing decline in area of occupancy (AOO): Unknown
Extreme fluctuations in area of occupancy (AOO): No
Estimated extent of occurrence (EOO) - km2: 2700
Continuing decline in extent of occurrence (EOO): Unknown
Extreme fluctuations in extent of occurrence (EOO): No
Continuing decline in number of locations: Unknown
Extreme fluctuations in the number of locations: No
Lower elevation limit (metres): 100
Upper elevation limit (metres): 600
Range Map: Click here to open the map viewer and explore range.

Population [top]

Population: The global population size has been estimated at c.80,000-90,000 individuals (S. Chan in litt. 2003), while the population in Japan has been estimated at c.100-100,000 breeding pairs.

Trend Justification:  The species is suspected to be declining at a slow to moderate rate, owing to habitat loss and degradation.
Current Population Trend: Decreasing
Additional data:
Continuing decline of mature individuals: Unknown
Extreme fluctuations: No Population severely fragmented: No
No. of subpopulations: 2-100 Continuing decline in subpopulations: Unknown
Extreme fluctuations in subpopulations: No All individuals in one subpopulation: No

Habitat and Ecology [top]

Habitat and Ecology: It inhabits dense undergrowth in damp areas within riparian broad-leaved evergreen forest and nests in crevices or among the roots of trees from May to August. It occurs from 100-600 m in different parts of its range. It is a partial migrant and in the winter many birds relocate to the southern islands of the archipelago (Brazil 1991).

Systems: Terrestrial
Continuing decline in area, extent and/or quality of habitat: Unknown
Generation Length (years): 6
Movement patterns: Not a Migrant

Threats [top]

Major Threat(s): Threats include predation by introduced mongoose (Okinawa) and weasels (Nakanoshima), and habitat loss resulting from commercial logging.

Conservation Actions [top]

Conservation Actions: Conservation Actions Underway
It is considered Vulnerable in the most recent national Red Data Book for Japan (Ministry of the Environment 2002). It makes use of artificial nest boxes that have been erected.

Conservation Actions Proposed
Monitor the species in order to detect populations declines. If declines are evident consider appropriate management actions including predator control and reducing commercial logging. Calculate its range size and the area of suitable habitat. Protect areas of suitable habitat.

Citation: BirdLife International. 2012. Erithacus komadori. The IUCN Red List of Threatened Species 2012: e.T22709685A38201237. . Downloaded on 02 December 2015.
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