Chinese Blackbird Turdus mandarinus 烏鶇
Category I. Common migrant and winter visitor, scarce but increasing breeding species in northwest New Territories.
IDENTIFICATION
Nov. 2019, Guy Miller. Adult male.
28–29 cm. A large, all-dark thrush. Plumage differences between the sexes are variable and can be quite muted. This obvious adult male is sooty black above and brownish to sooty-black below, with narrow orange-yellow eye-ring and orange to bright yellow bill; legs blackish to dark brown.
Jan. 2021, Kenneth Lam. First-winter male.
First-winter males are less black and show contrast between blackish primary coverts and tertials with browner flight feathers; in addition, the bill is less yellow.
Nov. 2015, Guy Miller. First-winter female.
This first-winter female is obviously browner, has faint scalloping on the underparts and shows contrast between the greyer primary coverts and browner flight feathers. The adult female is slightly browner than many adult males and has a paler chin and throat with broad darker streaks and a less distinct eye-ring.
May 2023, Paul Leader. Juvenile.
The juvenile is dark brown with variable paler buff mottling and streaking on the face and underparts.
VOCALISATIONS
A distinctive metallic ‘hyeev’ is heard from birds in flight.
Uttered when alarmed or anxious is a ‘chip’ or ‘choo’ given singly or short series.
The song is rather even in pitch and usually includes the disyllabic phrase ‘weet-hu’ or similar.
DISTRIBUTION & HABITAT PREFERENCE
Common and widespread in winter, Chinese Blackbird frequents lightly-wooded country, urban parks and occasionally more extensively-forested areas. It is most commonly recorded in the central, eastern and northern New Territories, but is also regularly noted on HK Island, the outlying islands and in Kowloon. There was, however, a decline in the percentage of occupied 1km squares from 20.7% to 8.2% between the Winter Atlas surveys of 2001-05 and 2016-19. The decline was widespread but proportionately greater on Lantau, Lamma and HK islands and the northwest and central New Territories.
The largest numbers are recorded in New Territories, including the Tai Mo Shan massif (Ng Tung Chai, Lam Tsuen valley, Shek Kong and Shing Mun), Mai Po, Tai Po Kau, Long Valley / Ho Sheung Heung and Shuen Wan. It is also frequent on Po Toi especially during autumn migration, where peak seasonal counts of over 20 birds are regular. Numbers on HK Island and Lantau are generally lower.
In summer, the breeding population is largely restricted to the northwest New Territories, where nests and juveniles have been reported at Mai Po, Lok Ma Chau, Palm Springs, Au Tau, Tuen Mun Park, Yuen Long Park and Tin Shui Wai Park. The percentage of occupied 1km squares double from 0.4% to 0.8% between the breeding bird surveys of 1993-96 and 2016-19.
OCCURRENCE
Chinese Blackbird is mainly an autumn passage migrant and winter visitor, occurring from the second week of October to the end of March, with a few individuals present in summer (Figure 1). A migratory peak occurs during November, while the wintering population appears established by the first week of October. Departure may begin as early as the first half of January after when numbers decline gradually through to April.
The highest count is 500 birds between Tung Chung and Sha Lo Wan on 24 November 1988; however, the highest count since 1999 is 130 birds at Ng Tung Chai on 18 November 2005. Most high counts are recorded in November and early December during migration.
Numbers vary somewhat each winter period (Figure 2). Winter 2004/05 apparently saw higher numbers, with peak counts of over 30 birds at eight localities (Ng Tung Chai, Pak Sha O, Wu Kau Tang, Mai Po, Lam Tsuen valley, Lai Chi Wo, Kei Lun Shan and Chinese University of HK). Ten years later in 2014/15 peak counts of over 30 birds occurred at six localities (Ng Tung Chai, Hang Tau, Mai Po, Long Valley, Yung Shue O and Shuen Wan).
Swinhoe (1861) stated that Chinese Blackbird was an ‘abundant resident’ in the areas he visited, which included HK, Macau and Guangzhou, though he made no specific reference to encountering it here. Kershaw (1904) noted it was ‘very common in winter’ in southeast China, though, again, not specifically HK. Thus the first definite mention of its occurrence in HK came from Vaughan and Jones (1913) who stated it was a scarce winter visitor (though common in Macau) and bred abundantly 50 miles inland. Herklots (1953) noted it was a winter visitor mainly from mid-November to March.
BEHAVIOUR, FORAGING & DIET
Often in flocks (sometimes large) in autumn and winter, frequently keeping to tree tops; roosts communally. However, foraging birds are often observed on the ground, and individuals often feed in the open on lawns in city parks. Omnivorous like other thrushes, has been seen feeding on fruits of Cinnamomum camphora and Schefflera heptaphylla. Ground-foraging birds are presumably searching for invertebrates, though detailed observations are lacking.
BREEDING
The first definite breeding record occurred at Fung Yuen, near Tai Po, where a juvenile and two adults were seen on 6 August 1995; a juvenile with two adults were seen again at this site on 19 May 1996 (Hackett 1996). Breeding then became rare during the 2000s, with only one juvenile seen (at Mai Po village on 28 June 2004). However, it has bred regularly since 2010, with an estimated breeding population of ten to 20 pairs in 2023, all in the northwest New Territories. The breeding population is largely confined to urban or urban fringe areas, especially city parks, with no records from more semi-natural woodland areas that may be utilised in winter.
Nest-building begins in late March, and juveniles have appeared from late May to early September.
RANGE & SYSTEMATICS
As a breeding species Chinese Blackbird is endemic to China in lowland areas from Guangxi and Sichuan northeast to at least Beijing, where it it also occurs as a migrant suggesting the breeding range extends further northeast. Birds winter to the south and southwest to north Indochina (del Hoyo et al. 2020, Birding Beijing 2022).
Two subspecies are recognised. T. m. mandarinus breeds in east China (from Shaanxi, Sichuan and Yunnan to Beijing), and winters in south China, Hainan and north Indochina. T. m. sowerbyi breeds in central China and winters in south China and Indochina (Cheng 1987). Based on this it would appear that sowerbyi is likely to be rare in HK. However, Etchécopar and Hüe (1982) state that when comparing a series of birds sowerbyi is more sooty than brown compared to mandarinus, which suggests identification in the field may be impractical.
CONSERVATION STATUS
IUCN: Least Concern. Population trend decreasing.
Figure 1.
Figure 2.
Birding Beijing (2022). https://birdingbeijing.com/the-status-of-the-birds-of-beijing/ (Accessed 18 July 2023).
Cheng, T. H. (1987). A Synopsis of the Avifauna of China. Science Press, Beijing.
del Hoyo, J., N. Collar, and D. A. Christie (2020). Chinese Blackbird (Turdus mandarinus), 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.chibla1.01
Etchécopar. R. D. and F. Hüe (1982). Les oiseaux de Chine, de Mongolie et de Coree: Passereaux. Papeete, Tahiti: Editions du Pacifique.
Hackett, J. A. (1996). The first record of Blackbird breeding in Hong Kong. Hong Kong Bird Report 1995: 252.
Kershaw, J. C. (1904). List of birds of the Quangtung Coast, China. Ibis 1904: 235-248.
Swinhoe, R. (1861). Notes on the ornithology of Hong Kong, Macao and Canton, made during the latter end of February, March, April, and the beginning of May 1860. Ibis 1861: 23-57.
