Justification This species has not been recorded since 1918, and no forest remains in the vicinity of the two known collecting localities, so it may have declined severely as a result of habitat destruction. However, it cannot be assumed to have gone Exitnct, because lowland forest in Sumatra has been relatively poorly surveyed, and the specimens were collected in 'exploited forest', hinting at a tolerance to some degree of habitat degradation. Any remaining population is likely to be tiny, and for these reasons it is treated as Critically Endangered.

Family/Sub-family Muscicapidae

Species name author (Oustalet, 1881)

Taxonomic source(s) Sibley and Monroe (1990, 1993)

Synonyms Cyornis ruecki Collar and Andrew (1988)

Identification 17 cm. Medium-large, blue flycatcher. Male mostly dark blue, becoming paler on forehead, rump and lower breast, white on belly. Slender, black bill and legs. Female has brown upperparts, becoming rusty on rump, tail and breast. Paler buff throat and belly. Similar spp. Male White-tailed Flycatcher C. concretus is larger, has paler blue forehead, fringes to wing feathers and distinct white outer tail feathers. Female has white on breast sides and tail sides. Male Pale Blue-flycatcher C. unicolor is paler blue with contrasting black lores. Female is duller brown on chest. Voice Undocumented. Hints Survey dense understorey habitat.

Population estimate

Population trend

Range estimate (breeding/resident)

Country endemic?

<50

unknown

-

Yes

Range & population Cyornis ruckii is known from two specimens collected in 1917 and 1918, at Tuntungan and Delitua in the lowlands of northern Sumatra, Indonesia. Two further specimens are purportedly from Malaysia, but their provenance has been questioned. The species must have always been very rare or local, given the failure of all but one zoological collector to obtain specimens.

Ecology: Its ecology is virtually unknown. Specimens were collected at 150 m and 200 m in "exploited forest", suggesting it may tolerate some habitat degradation. The fact that they were taken in January and April raises the possibility that the species may be migratory. Judging by its morphology, its closest relatives are to be found in the Hainan Blue-flycatcher C. hainanus group of China and South-East Asia: birds of tangled understoreys and secondary forest. However, as the species's taxonomic relationships remain unclear, a broad outlook should be maintained on its likely ecology.

Threats There is apparently no remaining forest cover at the two known collecting localities (they are situated on the outskirts of a large city: Medan), and its range may therefore have shrunk considerably. However, the description of its habitat as "exploited forest" raises the possibility that it may persist in adjacent disturbed wooded areas.

Conservation measures underway CITES Appendix II. This species has been protected under Indonesian law since 1972. The Wildlife Conservation Society is currently actively trying to locate this species in the lowlands surrounding Gunung Leuser National Park, and hope to expand this work in the future once additional funding has been secured¹.

Conservation measures proposed Examine the two skins in detail to improve understanding of its taxonomic status, and indeed (by consideration of wing length) to determine the likelihood of its being migratory. Conduct surveys (including use of mist nets) for the species between January and April in remaining forest patches ranging out from the two historical locations. Develop a conservation plan for the species, pending results of these surveys, including the establishment of protected areas, where appropriate, at any sites supporting populations.

References BirdLife International (2001). 1. N. Brickle in litt. (2007).

Further web sources of information

Fully detailed species accounts from the Threatened birds of Asia: the BirdLife International Red Data Book (BirdLife International 2001), together with new information collated since the publication of the Red Data Book

Text account compilers Phil Benstead (BirdLife International), Jeremy Bird (BirdLife International), Stuart Butchart (BirdLife International), Pete Davidson (BirdLife International), Andy Symes (BirdLife International), Joe Tobias (BirdLife International)

Contributors Nicholas Brickle (Wildlife Conservation Society)

IUCN Red List evaluators Jeremy Bird (BirdLife International), Stuart Butchart (BirdLife International), Andy Symes (BirdLife International)

Recommended citation BirdLife International (2009) Species factsheet: Cyornis ruckii. Downloaded from http://www.birdlife.org on 9/2/2010

This information is based upon, and updates, the information published in BirdLife International (2000) Threatened birds of the world. Barcelona and Cambridge, UK: Lynx Edicions and BirdLife International, BirdLife International (2004) Threatened birds of the world 2004 CD-ROM and BirdLife International (2008) Threatened birds of the world 2008 CD-ROM. These sources provide the information for species accounts for the birds on the IUCN Red List.

To provide new information to update this factsheet or to correct any errors, please email BirdLife

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