Velvet-fronted nuthatch
The []velvet-fronted nuthatch is a small passerine bird in the nuthatch family Sittidae found in southern Asia, from Nepal, India, Sri Lanka and Bangladesh east to southwestern China and Indonesia. Like other nuthatches, it feeds on insects in the bark of trees, foraging on the trunks and branches and their strongly clawed toes allow them to climb down tree trunks or move on the undersides of horizontal branches. They are found in forests with good tree cover and are often found along with other species in mixed-species foraging flocks. Adult males can be told apart by the black stripe that runs behind and above the eyes. They have a rapid chipping call note. They breed in tree cavities and holes, often created by woodpeckers or barbets.
Description
The velvet-fronted nuthatch has the typical nuthatch shape, short tail and powerful bill and feet. It is a small nuthatch, 12–13.5 cm long. It is violet-blue above, with lavender cheeks, buffy grey underparts, yellow eyes, and a whitish throat. The iris is distinctly pale and yellow. The bill is orange-red to bright red, and there is a black patch on the forehead and lores which is well developed in adults and less so in younger birds. The legs vary in colour between different subspecies. Young birds have a dark beak and dark tips to the undertail coverts. Adult males can be told apart by the black superciliary stripe that runs above the eye and over the head, towards the nape.Females lack the supercilium and have a warmer underpart colour. Juveniles are duller versions of the adult, lacking the black frontal band. The subspecies differ in shade and size and the distribution of white on the throat.
Taxonomy and systematics
Velvet-fronted nuthatches are very closely related to yellow-billed nuthatch S. solangiae and sulphur-billed nuthatch S. oenochlamys, with these three then next most closely related to blue nuthatch S. azurea. Some authors have placed this clade of four nuthatches in a separate genus Oenositta, but this would be inappropriate as the clade, although distinct in morphology, is nested within other Sitta species. The complex includes numerous forms which have had a confusing history, for instance S. oenochlamys has been treated as a subspecies of S. frontalis in the past. The species was first described validly by Swainson who also created the genus Dendrophila in which he initially placed the species; this was invalid as Hodgson had already used the name Dendrophila for a genus of partridges. Swainson used the species name given by Horsfield who had named the bird as Orthorynchus frontalis but Horsfield published only in 1821 giving priority to Swainson as the author.Subspecies
Five subspecies are currently accepted, though it has been argued that some could be treated as phylogenetic species:- S. f. frontalis – the nominate form, in the hill forests of southern India in the Western Ghats, the Eastern Ghats, the central Indian forests and in Sri Lanka, the Himalaya, and east through Indochina and the far south of China. Legs yellowish. The population along the Himalaya is included, although the name S. f. corallina has been proposed for this population with individuals being slightly smaller. The name S. f. simplex proposed by Koelz in 1939 for birds from the south of Bombay is also considered as a synonym. The Himalayan population extends from Uttarakhand east to Bangladesh and into Thailand, Myanmar, the Isthmus of Kra and possibly into Hong Kong where it may be an introduced species. The name S. f. chienfengensis was proposed by Tso-Hsin Cheng, 1964 for the birds of Hainan, China.
- S. f. saturatior – Malay Peninsula south of the Isthmus of Kra, Penang, Singapore, the Lingga Archipelago, and northern Sumatra. Legs brownish.
- S. f. corallipes – Borneo and adjacent Maratua Island. Legs bright orange-red.
- S. f. palawana – Palawan and Balabac in the western Philippines. Legs light brownish.
- S. f. velata – Java and southern Sumatra. Legs yellowish as in S. f. frontalis, but throat more extensively white.
Habitat and ecology
The velvet-fronted nuthatch is a resident breeder of all types of forests from deciduous to evergreen forest. In the Sunderbans, they are found in Sonneratia mangrove forests. They also live within secondary forest and make use of the shade trees in south Indian coffee plantations.Like other nuthatches they have strongly curved claws that allow them to climb down vertical tree trunks, unlike species such as woodpeckers that only work their way upwards. It moves jerkily up and down or around tree branches and trunks. It is an active feeder on insects and spiders, gleaned on the bark of the trunk and branches, and may be found in mixed feeding flocks with other passerines. The insects they disturb are sometimes taken by the racket-tailed drongo in Sri Lanka.
This is a noisy bird, often located by its repeated "sit-sit-sit" call.
Adults go through a complete postbreeding moult that begins at the end of June in northern India.
Plasmodium parasites including Haemoproteus have been detected in their blood. Feather mites of the genus Neodectes are found on the species.