IDENTIFICATION

VOCALISATIONS

The song is given throughout the year at all times of day. It is loud, insistent, monotonous and usually uttered for prolonged periods. The individual notes are delivered around 3-4 times a second, and there is some variation in how these are transcribed: ‘pwit’ with a clipped beginning and fall in pitch at the end, ‘dweet’, with a slightly nasal twang, and ‘dweep’, ‘chip’ or ‘choo’, all uniform in pitch and volume. These notes can also be delivered in a manner that suggests they are calls.

Non-song vocalisations include a downslurred ‘cheeoo’ repeated at a slower pace than the song.

Also an inflected ‘duwee’.

When two birds (presumed males) are interacting, the following may be heard.

DISTRIBUTION & HABITAT PREFERENCE

The breeding atlases of 1993-96 and 2016-19 recorded a small decline in the percentage of squares occupied from 66.8% to 64.8%, while the winter atlases of 2001-05 and 2016-19 recorded a slightly larger decline from 67.9% to 63.8%. It is unclear whether these differences are significant, but it is likely that the loss of village-edge marginal land may have had an impact.

Common Tailorbird occurs throughout Hong Kong, absent only from areas on Tai Mo Shan above approximately 700m and highly urbanised areas lacking vegetation. It is also present on larger offshore islands such as Tung Ping Chau, Sha Chau, Po Toi, Beaufort Island and the Ninepins.

It occurs in a wide variety of habitats from disturbed anthropogenic areas with limited vegetation through grassland-shrubland to open-canopy shrubland and the edge of closed-canopy forest, especially in dense clumps of tangled vegetation. Although widespread, it occurs in relatively low densities, which appear to be highest at the edge of secondary forest.

Noted by Swinhoe (1861), Kershaw (1904), Herklots (1953) and Dove and Goodhart (1955) to be a common resident.

OCCURRENCE

Although trapping indicates this species is almost entirely resident, a record of one at the former airport at Kai Tak on 25 November 1977 (Melville 1980) indicates that some movement occurs.

BREEDING

Nest-building has been noted only from 27 March to 1 April, which is perhaps an indication of how unobtrusive this species can be. Herklots (1953) stated that the nest is usually located within a few feet of the ground; however, Jansen (1959) refers to a nest site in the upper branches of a mango tree.

Jansen (1959) also provided a detailed account of the nest-building technique of Common Tailorbird. Leaves are punctured near the edge from the inside out so that the rough edges appear on the outer surface. Then a tiny wad of soft down or spider’s web is added to a piece of thread, before being moistened with saliva. This wad, with the thread passing through it, is inserted into the previously prepared hole, and the broken edges of the aperture stick to its sides to prevent its return. The same process is then used for the other end of the thread at the other side of the leaf. This pulls the edges of the leaf toward each other. Ten to fifteen of these spanning threads are installed in the lower part of the leaf drawing the sides toward each other to form a pocket, with a gap of 1.5-2.0 inches. Toward or at the end of this process begins the work of filling in the soft lining, the fibres of which interlock with the cross threads to form a firm wall between the edges of the leaf. If two leaves are used, two fibrous walls are created. The process is one of studding, rather than tying or stitching, as the bird’s name might imply. Ficus variegata is preferred, as the leaves are strong and thick, with Mangifera indica and Litsea monopetala also used. For the threads, in addition to spider web threads, fine rootlets and the thin fibres found on the trunk of Livistona chinensis are used.

Dependent juveniles, maximum three, have noted from 5 April to 9 September. It is known to be parasitised by Plaintive Cuckoo.

BEHAVIOUR, FORAGING & DIET

Common Tailorbird has a loud voice that it frequently uses and via which it usually makes its presence first known. It is territorial throughout the year, and squabbles between presumed males are a common feature of spring, in particular. Otherwise, it is generally rather unobtrusive as it generally forages fairly low down in denser vegetation; however, in forest it can also be seen in dense tree canopy or associated tangles of vines or creepers. It has a weak flight and usually only flies short distances. The only food items recorded are small invertebrates, their larvae and nectar.

RANGE & SYSTEMATICS

Resident from Pakistan east through the Indian subcontinent and Indochina to south China and south to peninsula Malaysia; a disjunct population occurs on Java (Madge 2020). In China occurs from Yunnan east through the coastal provinces, Jiangxi and Hunan as far north as Shanghai, including Hainan (Liu and Chen 2020).

O. s. longicauda occurs in north Vietnam and southeast China, including HK. Eight other subspecies are also recognised.

CONSERVATION STATUS

IUCN: Least Concern. Population trend stable.