Indochinese Yuhina Staphida torqueola 栗耳鳳鶥
Category I. Winter visitor to closed-canopy woodland and shrubland. Small numbers occur in summer and breeding is occasionally reported.
IDENTIFICATION
Dec. 2019, Michelle and Peter Wong.
14–15 cm. Small, rufous-brown yuhina with short dark grey crest, brown above, white below, with white-streaked chestnut ear-coverts; rather long tail with broad white tips on outer feathers.
Sexes similar. Juvenile is very like adult, but has upperparts tinged brown and edges of secondaries and wing coverts browner.
VOCALISATIONS
Contact calls are constantly uttered by flocks both when foraging and in flight.
DISTRIBUTION & HABITAT PREFERENCE
First recorded at Mount Nicholson on 25 November 1980, Indochinese Yuhina is typically found in relatively mature forest with a moderate to closed canopy. Tai Po Kau and mature forest on the Tai Mo Shan massif (such as Ng Tung Chai and Shing Mun) are favoured localities, but there are also numerous records at such sites as Tai Lam Country Park, Lau Shui Heung, Sha Tin Pass and Pak Sha O. They are occasionally seen at slightly more shrubby habitats such as Shek Kong catchment. Numbers at other sites are low, with few records on HK Island, Ma On Shan and the northwest New Territories. They are rarely seen on other outlying islands such as Lamma, Lantau and Cheung Chau, and there are no records on Po Toi Island.
The percentage of occupied 1km squares increased from 1.5% to 1.9% between the Winter Atlas surveys of 2001-05 and 2016-19. This is likely due to an increase in closed-canopy forest in the interim. The percentage of occupied squares was similar in the two breeding bird surveys of 1993-96 and 2016-19, standing at 0.4-0.5%.
OCCURRENCE
Most records of Indochinese Yuhina occur in winter from mid-October to the third week of January, and particularly from the third week of November to the third week of February (Figure 1). Previously regarded as an irruptive winter visitor (Carey et al. 2001), the pattern of records since 1999, and in particular since 2010 as a result of increased observer activity, suggests a less variable occurrence (Figure 2). Both the number of localities at which it is recorded and group sizes are larger. Although the number of observers has also grown in the last two decades, it is likely that the population increase is at least in part a result of the maturation and expansion of forests in most Country Parks in HK.
The highest count is 120 at Tai Po Kau on 3 January 2013,. Other high counts have been reported in Tai Lam Country Park (110 birds on 25 Nov 2019) and along Hoi Ha Road (110 birds on 14 March 2020). Records of large flocks greater than 30 are common.
There is evidence that a minority of birds are ex-captive. For example of four birds trapped at Kadoorie on 2 September 1996 two adults showed signs of captivity while the two juveniles appeared to have been reared in the wild.
BREEDING
Breeding was first confirmed at Kowloon Hills in 1994 (Tedbury 1995) and probably occurs in HK regularly, if not frequently or in widespread areas. Kowloon Hills was a favoured site in the 1990s, but since then most summer records have occurred in the Tai Mo Shan massif. Evidence of a breeding pair was recorded in early spring at Ng Tung Chai on 12 April 2004 and 18 March 2017, while juveniles have been seen at several locations, including Sha Tin Pass (22 June 2004), Lion Rock Country Park (16 June 2012 and 27 April 2014) and Ng Tung Chai (23 April 2017).
BEHAVIOUR, FORAGING & DIET
Usually occurs in noisy single species flocks moving through the canopy or restlessly flying between foraging areas. There is little local data regarding diet, but consumption of caterpillars has been noted. Flocks may remain for a number of weeks, albeit roving around a relatively large area.
RANGE & SYSTEMATICS
Monotypic. Occurs in south and southeast China (Sichuan, Yunnan, Hubei, Zhejiang, Guangxi and Guangdong, including HK) (Liu and Chen 2020), north Thailand, Laos and Vietnam (Collar and Robson 2021).
CONSERVATION STATUS
IUCN: Least Concern. Population trend unknown.
Figure 1.
Figure 2.
Collar, N. and C. Robson (2021). Indochinese Yuhina (Staphida torqueola), version 1.1. 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.indyuh1.01.1
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.
Tedbury, G. (1995). Striated Yuhina breeding in Hong Kong. Hong Kong Bird Report 1994: 221.
