IDENTIFICATION

RANGE & SYSTEMATICS

The White Wagtail Motacilla alba breeds in almost all Eurasia from above the Arctic Circle south to the south coast of China; it winters in western and southern Europe, Africa north of the Equator, the Middle East and the Indian subcontinent east to south China and east Asia and south to peninsula Malaysia. Polytypic species of many taxa. Those recorded in HK are leucopsis, ocularis, lugens and personata.

The locally-breeding M. a. leucopsis breeds from the Primorsky region through northeast China, the Korean peninsula and southwest Japan to much of east and southeast China, including Taiwan and Hainan; it winters in China from Beijing (where scarce) south through the east and south of the country to northern Indochina and the northeast part of the Indian subcontinent (Badyaev et al. 2020, Birding Beijing 2022).

VOCALISATIONS

The typical flight call is a double note ‘chee-chik’; also ‘chik’ or ‘chee-chik-chik’. Sometimes similar to that of Grey Wagtail.

The ‘twittering song’ (Alström et al. 2013) is the more complex song type.

The simple variant of the song is the ‘advertisement call’ (Alström et al. 2013).

The following vocalisation is given in flight when approaching foraging areas, especially early morning.

DISTRIBUTION & HABITAT PREFERENCE

Wetland-associated, and thus frequently seen near water but not dependent on it, most open-country rural habitats are utilised apart from grassland and grassland-shrubland. Migrants are seen in substantial numbers in the fish pond areas of Deep Bay, while larger nocturnal roosts are generally reported from urban areas.

Most reports of breeding activity are from the northwest New Territories, in particular Deep Bay and its hinterland, and the central New Territories (Kam Tin, Lam Tsuen, Shek Kong, Tai Po). There are fewer reports from the northeast and west New Territories, HK Island, Kowloon and Sai Kung, though this may to some extent reflect observer activity. On Lantau such reports have come from the airport island at Chek Lap Kok, Pui O, Shui Hau and Mui Wo. Breeding on offshore islands has only been reported from Po Toi and Cheung Chau.

OCCURRENCE

M. a. leucopsis is a common passage migrant and winter visitor, and a locally common breeding species (Figure 1). Numbers are highest from the second week of October to the third week of February. Highest numbers are present from the second week of January to the second week of February. A feature of the latter period is the appearance of larger numbers of males around fish ponds, which may be a response to colder weather further north or it could mark the beginning of northward passage. The highest count of birds away from a roost site is 250 at San Tin on 12 February 2017. By early April it is largely the breeding population that is present, which remains the case until late July or early August.

Many reports of White Wagtail do not differentiate between leucopsis and ocularis, though the former massively predominates usually. The highest such count is 3,000 roosting at Mai Po NR on 24 October 1992.

Kershaw (1904) referred to leucopsis as the commonest resident wagtail, and Vaughan and Jones (1913) reported it to be mainly a winter visitor with a few pairs remaining to breed both at the coast and inland in Guangdong. In contrast, Herklots (1934, 1953) stated that ocularis was ‘undoubtedly the commonest wagtail during the winter’; he also described leucopsis as a common winter visitor and considered it probable that a few might remain for the summer, though there were no records outside the period from mid-September to April.

BREEDING

Vaughan and Jones (1913) reported breeding in nearby Guangdong and stated that in June birds evidently breeding were seen in HK.

The first modern breeding record occurred on 13 May 1959 when an adult and a juvenile were observed at Kai Tak and a bird was in song in the summer of 1961. Herklots (1967) reported that birds had been seen on several occasions in summer at Kai Tak entering possible nest sites. The 1990s witnessed a marked upsurge of breeding records, to such an extent that by the end of the decade breeding leucopsis were found in much of the northwest New Territories, as well as areas such as the airport at Chek Lap Kok, Yim Tso Ha, Shuen Wan, Sha Tin, Tai Wai and Mui Wo.

Nesting has been noted as early as 28 January, and the collection of nest material has been observed up to 28 March. Food-carrying has been noted up to 7 April. The earliest record of an unfledged juvenile occurred on 15 March, and that of fledged birds on 21 March. Most reports of fledged juveniles occur in April and May, though there are records of ‘recently-fledged’ young up to 15 June suggesting a second brood.

Pairs are now established in such places as areas of fish ponds and wet agriculture, rural areas with low-density housing, residential housing estates with suitable areas of irrigated landscaping and artificial ponds.

BEHAVIOUR, FORAGING & DIET

Forages by walking or running after insects, and occasionally by leaping up to catch them mid-air or after a short aerial pursuit. Tail-pumping is frequently conducted while walking and perched, and at a greater speed upon landing or after running.

As with its congeners, White Wagtail is a communally-roosting species, and from at least the late 1950s to the winter of 1980-81 up to 500 birds regularly roosted in the Statue Square area in the core urban area of Central, HK Island. Other roosts in urban areas recorded during this period were at Nathan Road, Kowloon and the Kowloon side of the Star Ferry terminal. White Wagtails were also noted roosting in a sugar cane field at Mong Tseng in late February 1967, the maximum count being 300. It was also recorded roosting in reedbeds at Mai Po from at least 1984; counts there in 1992 indicated that numbers peaked during migration as 1,000 birds were recorded on 5 October rising to 3,000 on 24 October, but only 700 were present on 5 December.

CONSERVATION STATUS

IUCN (Motacilla alba): Least Concern. Population trend stable.