Yellow-legged Buttonquail Turnix tanki 黃腳三趾鶉
Category I. Rare passage migrant to open-country grassy areas, though distressed birds occur in atypical habitat.
IDENTIFICATION
Oct. 2018, Leo Sit. Female/immature.
15-18 cm. Tiny and rotund, about 75% of the size of Japanese Quail. Largely yellow bill and surprised expression imparted by white iris and prominent dark pupil. Scapulars and coverts with large blackish centres and buff to greyish fringes; mantle feathers with blackish subterminal bands and pale tips. Legs and most of bill (excluding tip) yellow. Males are rather orange-brown on the head and underparts, while females and immatures are slightly duller and greyer.
Oct. 2020, KWOK Chi Tai. Male.
When flushed into a fast whirring flight, shows yellowish bill (and legs under favourable viewing conditions), rufous head and neck (on male) and marked contrast between pale upperwing coverts and darker flight feathers.
VOCALISATIONS
Appears not to vocalise away from the breeding grounds.
DISTRIBUTION & HABITAT PREFERENCE
The preferred habitat is dense grassy or rank vegetation, but it can be seen almost anywhere away from wetlands, including urban areas. Consequently, it has been recorded in scattered localities throughout HK.
OCCURRENCE
Yellow-legged Buttonquail has been reported as an autumn passage migrant from 20 September to 23 November, with the main passage period occurring from the first week of October to the first week of November (Figure 1). Only ones or twos have been noted.
There are three winter records of live birds, on 27 December 2011, 4-5 January 1996 and 26 January 1999, though it is possible that one or more of these were ex-captive.
The only spring record is of an ‘unkempt and tired bird’ on 10 April 1962 at Pok Fu Lam. While this could have been a distressed migrant, given the lack of spring records since then, the likelihood is this was also ex-captive.
Vaughan and Jones (1913) stated that Yellow-legged Buttonquails passed through the New Territories on migration but were most numerous in autumn. La Touche (1931-34) wrote that it was abundant in Fujian and Guangdong in October and November, and some remained during the winter.
BEHAVIOUR, FORAGING & DIET
The quality of view obtained of Yellow-legged Buttonquail is likely to be at the extremes of fleeting and poor or extremely good. On most occasions birds are flushed from dense grassy vegetation, almost underfoot, and the only view is as the bird whirrs away in its fast flight to another patch of dense cover. It then runs off, and it is rare to flush it twice. Otherwise, they are often seen in unlikely areas, presumably disoriented on migration, at close range. Birds are not infrequently rescued in a distressed state and taken in for recovery and rehabilitation at Kadoorie Wild Animal Rescue Centre.
RANGE & SYSTEMATICS
Occurs from the Indian subcontinent east through Indochina to much of south, east and northeast China and adjacent parts of Ussuriland, the Korean peninsula and south through much of mainland southeast Asia. Populations in northeast Asia and Pakistan are summer visitors (Debus and Kirwan 2020). In China breeds in the northeast and winters south of the Yangtze including Hainan and Taiwan (Liu and Chen 2020). Based on HK records, however, it may be rare in winter in south China.
Two subspecies are recognised: T. t. blanfordii breeds in from Myanmar east and south, while the nominate breeds in Pakistan and India.
CONSERVATION STATUS
IUCN: Least Concern. Population trend stable.
Figure 1.
Debus, S. and G. M. Kirwan (2020). Yellow-legged Buttonquail (Turnix tanki), 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.yelbut1.01
La Touche, J. D. D. (1931-34). Handbook of the birds of Eastern China Vol. 2. Taylor and Francis, London.
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.
Vaughan, R. E. and K. H. Jones (1913). The birds of Hong Kong, Macao and the West River or Si Kiang in South-East China, with special reference to their nidification and seasonal movements. Ibis 1913: 17-76, 163-201, 351-384.