Sumatran Frogmouth
Batrachostomus poliolophus
A Sumatran endemic, this medium-sized nightbird is limited to foothill and montane forests between 1200 and 2000 meters, only rarely straying to lower elevations. Nocturnal and difficult to see by day as it perches quietly in the middle levels of forest. A relatively short-tailed species, Sumatran has extensive clean white scaling on the underparts. Gives a variety of vocalizations, including an eerily falling whistled trill, as well as various squawks, shrieks, and shorter whistles. Altitudinal range mostly separates it from other small frogmouths, but in situations of potential overlap, note short tail, well-demarcated (not messy) and extensive white scaling on underparts, and different vocalizations.
识别特征
B. poliolophus has a large, arched bill with a light-brown to straw-yellow color. Its face is adorned with bristles, mainly on the forehead and ear coverts. It can be distinguished from other frogmouths by its tail, which is considerably shorter than its wings. It is sexually dimorphic. Males are mostly a dull dark brown with some black speckling and have a collar of white to pale buff feathers. Their underside is a lighter brown with black bars. A pattern of cream-buff spots covers the throat, sometimes extending to the breast and belly. The plumage of females is mainly rufous-brown with faint black barring. Unlike the males, the underside is generally of a similar color to the wings. The greater coverts and the upper breast sometimes exhibit white spots. The colar is variable, but generally similar to that of males.
分类信息
This species is one of twelve others in its genus. The genus Batrachostomus is one of the three in the frogmouth family (Podargidae). The genus name is derived from the Greek for frog (batrakhos) and mouth (stoma). Poliolophus is Greek for "grey crest".<p>The Bornean frogmouth was once considered to be a subspecies of B. poliolophus.
- 学名
- Batrachostomus poliolophus
- 命名信息
- Hartert, EJO, 1892
- 目
- Caprimulgiformes
- 科
- Podargidae
- 属
- Batrachostomus
分布与栖息地
This species is native to the Barisan mountains of the island of Sumatra. It is known to inhabit lowland and montane tropical forests with elevations ranging from 600 to 1200 meters.
- 迁徙
- Resident species
行为
Due to the rarity and nocturnal nature of this species, very few observations of its behavior have been published.<p>The vocalization of this species has been described as an undulating whistling accompanied by 5–7 notes ("wa") with a descending pitch. Other calls include repeated and wavering "weeeow" notes, as well as a repeated, high pitched whistle sound ("tsiutsiu"). Some sources describe these vocalizations as having a wheezing or asthmatic quality.<p>This species is known to feed on insects such as crickets and small beetles.<p>The nest of B. poliolophus is described in one account as being very small relative to the size of the adult bird. The main material used in the construction of nests was parental down, as well as organic matter such as lichen or moss. The clutch consisted of a single, white egg of an oval shape. This species has a generation time of 7.5 years.
保护状况
- 种群趋势
- declining
照片
分布
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