Pale-footed Bush Warbler Urosphena pallidipes 淡腳樹鶯
Category I. Rare winter visitor.
IDENTIFICATION
Oct. 2020, Michelle and Peter Wong.
11-12.5 cm. The most striking plumage features are the extensive pure white throat contrasting with greyish-buff flanks and very dark and well-marked eye stripe behind and in front of the eye. The upperparts are fairly rich dark brown. Legs strikingly pale greyish-pink, lower half of the orbital ring white and distinct, upper mandible and distal half to the lower mandible dark with a pinkish base to the latter. Very short primary projection. Superficially like Asian Stubtail but less striking supercilium and the obvious length in the tail distinguishes.
VOCALISATIONS
A vocal species for which both low-intensity song and call have been heard in HK.
When excited or alarmed, a loud and emphatic, slightly rolling ‘trrk’ or longer ‘trrrrrrk’, higher in pitch and more rolling than that of Manchurian Bush Warbler. More relaxed birds give a fairly deep but loud ‘chek’, which is a very short version of the above call.
The song heard in HK is generally not fully-developed and has generally been in response to playback when it is interspersed with the excitement calls described above.
DISTRIBUTION & HABITAT PREFERENCE
Occurs in dense shrubby vegetation and has been found at a variety of sites including the landscaped podium of a residential estate in Kowloon, reed marsh at Mai Po, hillside shrubland at Kadoorie Agricultural Research Centre, low shrubs alongside a stream on Tung Lung Chau and shrubby grassland at Wo Hop Shek.
OCCURRENCE
The first record was of a bird trapped on 6 October 1990 (Melville et al. 1991), and the following six records to 8 November 1998 were also trapped. The next record did not occur until 30 November 2007, after when there were a further five records until 29 September 2019. Winter 2020-21 proved exceptional for the species with five birds recorded until the end of 2020. Unlike the earlier period, most records since 2007 involve birds seen in the field. Extreme dates are 28 September and 24 February.
BEHAVIOUR, FORAGING & DIET
Skulking and difficult to see as it forages in dense vegetation, often near the ground. Males, at least, respond strongly to playback.
RANGE & SYSTEMATICS
The nominate subspecies occurs from north India east to north Myanmar and southwest China, while U. p. laurentei occurs southeast and east of here in north Indochina and southwest China. In China resident in Yunnan, Guangxi and north Guangdong. Some birds move south in the non-breeding season. Has possibly expanded eastward in recent years. A third subspecies, U. p. osmastoni occurs on the Andaman Islands (Clement 2020, Liu and Chen 2020).
CONSERVATION STATUS
IUCN: Least Concern. Population trend unknown.
Clement, P. (2020). Pale-footed Bush Warbler (Urosphena pallidipes), version 1.0. In Birds of the World (J. del Hoyo, A. Elliott, J. Sargatal, D. A. Christie, and E. de Juana, Editors). Cornell Lab of Ornithology, Ithaca, NY, USA. https://doi.org/10.2173/bow.pfbwar1.01
Liu, Y. and Y. H. Chen (eds) (2020). The CNG Field Guide to the Birds of China (in Chinese). Hunan Science and Technology Publication House, Changsha.
Melville, D. S., A. C. Galsworthy and P. J. Leader (1991). Pale-footed Bush Warbler: a species new to Hong Kong. Hong Kong Bird Report 1990: 111-116.
