Species of bird
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The Chinese nuthatch or snowy-browed nuthatch (Sitta villosa) is a species of bird in the family Sittidae. It is a small nuthatch, measuring in length. The ;dfn id="" ;upperparts ;/dfn ; are blue-gray and the ;dfn id="" ;underparts ;/dfn ; from a dull buff-grayish to a cinnamon-orange; the cheeks are white. There is a marked sexual dimorphism: the adult male is distinguished by its very black ;dfn id="" ;crown ;/dfn ;, while that of the female is the same blue-grey as the back, or at most dark gray when the plumage is worn. In both sexes, a dark gray ;dfn id="" ;eyestripe ;/dfn ; extends in front of and behind the eye, topped by a clear white supercilium separating it from the crown. The song is variable, and composed of repetitions of small invariant whistles. The species feeds mainly on insects in summer and completes its diet with seeds and fruits. The nest is generally placed in the hole of a conifer. The pairs raises one brood per year, with five or six chicks.
The Chinese nuthatch lives from central China to the northeast of the country, as far as Korea and the extreme southeast of Russia. Up to three subspecies are distinguished, "S. v. villosa", "S. v. bangsi" and "S. v. corea", with slightly different distributions and colorations. The Chinese nuthatch is phylogenetically related to the Corsican nuthatch ("S. whiteheadi") and both species are themselves closely related to the North American red-breasted nuthatch ("S. canadensis"). Because the bird's range is so large and numbers do not appear to decline significantly, the International Union for Conservation of Nature considers the species to be of "least concern".
Taxonomy.
Nomenclature and subspecies.
The Chinese nuthatch was described in 1865 by the French ornithologist Jules Verreaux, based on specimens sent from Beijing by the missionary Armand David in 1862, who also referred to it as "Sitta pekinensis" in 1867. Verreaux described the species as close to red-breasted nuthatch ("Sitta canadensis") but with long, silky plumage, and thus gave the specific name "villosa", from the Latin for "hairy". German ornithologist Hans Edmund Wolters proposed the division of the genus "Sitta" into subgenera in 1975–1982. The Chinese nuthatch is placed in "Sitta" ("Micrositta"). According to the International Ornithological Congress there are three subspecies:
The Japanese ornithologist Toku Tarô Momiyama also later used the name "Sitta villosa yamashinai" , but this name is not associated with any valid scientific description and therefore is a nomen nudum.
Molecular phylogeny.
In 1998, Eric Pasquet studied the cytochrome-b of the mitochondrial DNA of a dozen nuthatch species, including the various species of the "Sitta canadensis" group, which are also those that comprise the subgenus "Micrositta": "canadensis", "villosa", "yunnanensis", "whiteheadi", "krueperi" and "ledanti". The Yunnan nuthatch ("S. yunnanensis") is not included in the study. Pasquet concludes that the Chinese nuthatch is phylogenetically related to the Corsican nuthatch ("S. whiteheadi") and the red-breasted nuthatch, these three species form the sister group of a clade including Krüper's nuthatch ("S. krueperi") and the Algerian nuthatch ("S. ledanti"). The first three species would even be close enough to be conspecific. For the sake of taxonomic stability, however, all retain their status as species in their own right. In 2014, Eric Pasquet and colleagues published a phylogeny based on nuclear and mitochondrial DNA of 21 nuthatch species and confirmed the relationships of the 1998 study within the "canadensis group", adding the Yunnan nuthatch, which was found to be the most basal species of the group.
Biogeography.
With its phylogeny established, Pasquet concludes that the paleogeographic history of the group would be as follows: the divergence between the two main clades of the "canadensis group" appears to have occurred more than five million years ago, at the end of the Miocene, when the common ancestor of "krueperi" and "ledanti" entered the Mediterranean basin at the time of the Messinian salinity crisis; the two species diverged 1.75 million years ago. The other clade split into three, with populations leaving Asia for the east, giving rise to the red-breasted nuthatch, and then from the west, about one million years ago, marking the separation between the Corsican and Chinese nuthatches.
Description.
Plumage and measurements.
The Chinese nuthatch is a small nuthatch, measuring in length.[fn. 1] The ;dfn id="" ;upperparts ;/dfn ; of the Chinese nuthatch are blue-gray, with the ;dfn id="" ;crown ;/dfn ; shiny black to dark gray; the ;dfn id="" ;underparts ;/dfn ; are light, ranging from dull buff-gray to cinnamon orange. The coloration varies a bit depending on the sex, plumage wear and subspecies. The species has a marked white supercilium, as well as a more or less well defined black ;dfn id="" ;eyestripe ;/dfn ;. The bill is thin and pointed, with the edge of the upper mandible (the ;dfn id="" ;culmen ;/dfn ;) straight, which may give the impression that the tip of the bill is rising upwards. The bill is slate-black, with the base of the lower mandible blue-gray. The ;dfn id="" ;iris ;/dfn ; is brown to dark brown, and the legs and toes are dull, blue-gray to brownish-gray.
There is a marked sexual dimorphism: the male has a very black crown and a clear black eyestripe framing a contrasting white supercilium, while in the female the crown is barely darker than the rest of the upperparts in fresh plumage, becomes a darker and more contrasting sooty-grey, especially on the forehead, and in some cases the entire crown is sooty-black. Its eyestripe is also less well defined, duller, and its supercilium thinner. The female is overall duller than the male, notably with the scapulars less vivid, the wing feathers edged with brown and the underparts darker and less colored. The juvenile male has a blacker crown than the darker female, but still less black and less bright than the adult male; its underparts are darker and more cinnamon-colored. In the nominate subspecies, juveniles also have cinnamon edging on their wing feathers, whereas the adult feather edges are generally duller, tending to gray. In the subspecies "S. v. bangsi", adults have cinnamon feather margins, and are overall more colorful than subspecies "S. v. villosa", with the male having orange-cinnamon and the female dull buff-cinnamon and dull underparts. However, in late winter, both subspecies have paler and fairly similar colorations. The subspecies "S. v. corea" is paler, more grayish, and smaller than the nominate subspecies
Similar species.
This species is locally found in sympatry with the Eurasian nuthatch (S". europaea"), but differs from it in its smaller size, clearly visible white supercilium, black crown in males, and relatively plain underparts, lacking the reddish undertail coverts and flanks. In the west of its range, the Chinese nuthatch can also be found with Przevalski's nuthatch ("S. przewalskii"), and both have brightly cinnamon-colored underparts. The Chinese nuthatch is easily distinguished by its black eyestripe, while Przevalski's nuthatch has very light cheeks contrasting with the breast. The Chinese nuthatch is phylogenetically and morphologically very close to the Corsican nuthatch, which is, however, endemic to Corsica and generally has much less vivid underparts; a Chinese nuthatch in worn plumage has underparts that are just more buff than a Corsican nuthatch in fresh plumage. Both species are closely related to the red-breasted nuthatch, which has even brighter underparts, with a more prominent eye streak.
Ecology and behavior.
Vocalizations.
The Chinese nuthatch sings on the top of pine and spruce trees. British ornithologist Simon Harrap gives three basic types of calls. The first is a harsh, prolonged "schraa", "schraa" call, reminiscent of the Eurasian Jay ("Garrulus glandarius"), and similar to some calls found in the Corsican nuthatch, Algerian nuthatch, and Krüper's nuthatch. Given, in agitation or excitement, singly or in irregular series at intervals of 0.31-1 second. The second type is a various quiet, conversational, single short units, more melodic or piping and repeated in series of "whip", "whip whip..." or "quip-quip-quip", sometimes becoming a "quit", "quit..." squeak. The song is composed of this type of calls, in number from five to thirty, the volume increasing in the first part of the song. Small ascending whistles are also emitted, at a rate of seven notes per second and for 1.5 to 2.25 seconds, sometimes introduced by a higher note, forming a "tsi-pui-pui-pui-pui..." A variant is a much flatter, less musical and more monotous rattle (c. 12 units per second), "duiduiduidui...", recalling song variants of chestnut-vented nuthatch in speed of delivery and duration, but a little mellower and lower-pitched. The last type of call consists of short, nasal notes, "quir", "quir", produced in long, very rapid series, or in an irregular manner.
Food.
In summer, the Chinese nuthatch feeds almost exclusively on insects, which are also the sole source of food for the young. From April to August, studies in China showed that 98.5% of its diet consisted of insects, including beetles ("Coleoptera"), "Hymenoptera", butterflies, bugs ("Heteroptera"), "Homoptera" (including "aphids" and "Cicadidae"), "Neuroptera" and flies ("Diptera"). It consumes larger insects by holding them with its legs and shredding them with its bill; it can also capture insects in flight. Like other nuthatches, the Chinese nuthatch stores food. In winter, the Chinese nuthatch's diet consists primarily of nuts, seeds, and tree fruits. The species often takes part in mixed-species foraging flocks in winter, where it is observed in pairs.
Breeding.
In Jilin, the breeding season takes place from late April to early May. The nest is usually placed high in the cavity of a conifer (more than above the ground, on average), but can also be built in a rotten stump or in an old building. Nest entrance is about in diameter (does not apparently, daub the nest hole with mud or resin). Both partners build the nest within seven to eight days, making a bowl from plant fibers, feathers, and grasses. The egg–laying has four to nine eggs – usually a clutch of five or six: eggs white, marked with reddish-brown and measuring . The female incubates alone while the male feeds her, and the young hatch from the egg after 15–17 days of incubation. Both parents participate in their feeding, and raise only one brood in a year.
Parasites.
A feather mite, "Pteroherpus surmachi", was described from the Chinese nuthatch in 2011 by Russian arachnologist Sergei V. Mironov.
Distribution and habitat.
The Chinese nuthatch is distributed over northeast China, Korea, and the extreme southeast of Russia. It has been reported from the Russian island of Sakhalin, but may only be a vagrant there. In China, it ranges from eastern Qinghai in the west to southeastern and central Gansu, most of Shaanxi, Shanxi, southern Liaoning on the Liaoning peninsula, northern Hebei, Beijing Municipality, and northern Sichuan. It was recorded from northern North Korea, with some dispersal into surrounding areas in autumn; it was observed in North Hamgyong in July–August and, in May–November, in North Kyongsang, including North P'yongan. It is a very rare winter visitor in South Korea, with records from the mountains of Kyonggi (October–March, also July 1917) and North Kyongsang in November; the only recent South Korean record is from the Kwangnung Experimental Forest, near Song, Kangwon province, in March 1968. In the peninsula, it is closely associated with Japanese Red Pine ("Pinus densiflora") forests. In China, it inhabits coniferous forests ("Pinus", "Picea"), sometimes mixed with oaks ("Quercus") and birches ("Betula").
In the summer of 2006, Dutchmen on an entomological expedition incidentally observed a pair of nuthatches nesting in the Altai, more or less on the crossing of China, Kazakhstan, Mongolia, and Russia, in a pure larch ("Larix" sp.) forest at altitude. They observed that the male had a black crown, the female without black crown, and said that both have a distinct dark eyestripe topped by a white supercilium. If the European nuthatch is present in the region (subspecies "asiatica"), the observers assure that the black crown of the male and the small size of the individuals exclude a misidentification with this Eurasian species. The closest species geographically that could fit this description is the Chinese nuthatch, which would then be far from its known distribution ( from the breeding range), and which has more buffy underparts than the observed individuals. To observers, this record could be indicative of a much wider distribution of the Chinese species, or the bird could be an as yet undescribed species related to "S. whiteheadi" and "S. villosa". These two species with