Plain Swift
Apus unicolor
Medium-sized swift, very similar to Common Swift, but is noticeably paler, especially against a dark background. Wings are narrower and very pointed and the tail is longer and more deeply forked than Common or Pallid Swifts. Pale throat patch not distinct and difficult to see. Flight is very fast, agile, and erratic. Gives a shrill, wheezy scream that “hiccups” at the end. Breeds primarily on Madeira and the Canary Islands, but may move to North Africa in winter.
识别特征
The plain swift (Apus unicolor) is a medium-sized swift. Although this bird is superficially similar to a barn swallow or house martin, it is not related to those passerine species. The resemblances between the groups are due to convergent evolution reflecting similar life styles. Swifts have very short legs that they use only for clinging to vertical surfaces. They never settle voluntarily on the ground, and spend most of their lives in the air, feeding on insects that they catch in their beaks. They drink on the wing. Plain swifts breed in colonies on cliffs, bridges and buildings on the Canary Islands and Madeira, laying two eggs in a saucer-shaped nest made of flowerheads glued with saliva. They are partially migratory, with many birds leaving to winter in mainland Africa. Until recently it was thought that the birds wintered on the African coast but recent studies suggest they travel much further to the equatorial forests of Liberia and Guinea, a distance of 2,600 kilometres. Small numbers are also believed to breed in Morocco between Agadir and Essaouira, where a colony was found on coastal cliffs and possibly also in Mauritania where there are frequent sightings. Small breeding colonies have recently been discovered in mainland Portugal, in Lisbon and Porto. This 14–15 cm long species is very similar to the closely related common and pallid swifts, which also occur in the archipelagos, and separation is only possible with good views. Like its relatives, it has a short forked tail and very long swept-back wings that resemble a crescent or a boomerang. It is entirely dark except for an indistinct pale throat patch. It is slimmer and more rakish than the pallid swift, and is darker than that species and lacks the obvious white throat. Distinguishing the plain swift from the similarly plumaged common swift is much more difficult, although juvenile common can be easily eliminated due to its white throat. The plain is slimmer and appears longer winged than the common, and has scaly underparts, difficult to see except with excellent views. The call is a loud dry scream similar to that of the common swift, though possibly higher pitched.
分类信息
Genus: Apus; Family: Apodidae; Order: Apodiformes.
- 学名
- Apus unicolor
- 命名信息
- (Jardine, 1830)
- 目
- Apodiformes
- 科
- Apodidae
- 属
- Apus
分布与栖息地
Breeding range: AF : Madeira (all islands) and Canary is. (all islands; nc to c Macaronesia, nw of n Africa); may breed adjacent Moroccan coast. Non-breeding range: to adjacent Moroccan coast.
- 繁殖区
- AF : Madeira (all islands) and Canary is. (all islands; nc to c Macaronesia, nw of n Africa); may breed adjacent Moroccan coast
- 非繁殖区
- to adjacent Moroccan coast
- 迁徙
- Complete migrants
行为
Migration pattern: Complete migrants.
保护状况
- 种群趋势
- unknown
照片
分布
鸟叫声
其他鸟类
Pale-breasted Illadopsis
Illadopsis rufipennis
A chunky, mid-sized, remarkably drab babbler with a white throat and brownish breast. Found in the understory of rainforest at low and middle elevations, usually in small groups. Shy and skulking; rarely seen unless searched for. Very similar to Brown Illadopsis, but slightly different vocally, with higher and more inflected whistles. Also slightly paler below and more richly colored above, with a cleaner white throat. Most often detected by voice. The highly variable song consists of single-note pure whistles or short whistled phrases separated by pauses, often in a three-note ascending series; listen for a haunting clear monotone whistle. Also gives scolding calls, sometimes accompanying the whistled song.
Cozumel Emerald
Cynanthus forficatus
Only on Cozumel Island, Mexico, where it is usually the most frequently encountered hummingbird. Feeds low to high on a variety of flowers, preferring forest edge, gardens, and other semi-open habitats. Male is stunning, emerald-green with a long, deeply forked tail. Female has distinctive broad dark facemask, rather long forked tail. No similar species on the island (Canivet’s Emerald occurs on the Yucatan mainland).
Fox's Weaver
Ploceus spekeoides
A chunky, short-tailed, long-billed weaver. Breeding males are mostly yellow with a black face mask, a pale eye, and a mostly black, yellow-streaked back. Females are much duller, brownish-olive overall and pale yellow below. Found very locally in Uganda, in swamps within savanna. Similar to Heuglin’s Masked-Weaver, but larger, and males have a darker back. Vocalizations are typical of weavers: “chek” notes and a squealing, sizzling “radio static” song.
开始您的观鸟之旅
在户外识别鸟类，并在下一次观察时随手查阅鸟类图鉴。