Yucatan Gnatcatcher
Polioptila albiventris
Tiny gray and white bird with cocked tail. Local in dry tropical scrub of northern Yucatan Peninsula. Male has a black cap, solid in breeding season, but with narrow white eyebrow in non-breeding season. Female has gray cap with narrow white eyebrow year-round. Told from Blue-gray Gnatcatcher by face pattern: Blue-gray has a white eyering, not a white brow.
识别特征
The Yucatan gnatcatcher is 10 to 12 cm (3.9 to 4.7 in) long. Six males weighed 5.4 to 6.2 g (0.19 to 0.22 oz) and three females 5.0 to 5.7 g (0.18 to 0.20 oz). The female's upperparts are plumbeous gray from the crown to the rump. Its underparts are white with sometimes a pale grayish wash on the flanks. The tail's central feathers are black and each pair out from them are progressively more white until the all white outermost pair. It has a narrow white supercilium. The male's basic (non-breeding) plumage is essentially the same. Its alternate (breeding) plumage is also similar with the addition of a black cap that extends to the middle of its eye.
分类信息
The Yucatan gnatcatcher is monotypic. <p>"The continually changing species to which albiventris has been allied gives testament to the general confusion that has afflicted the classification of most Central American Polioptila taxa." It was originally described as a full species. It was later variously considered a subspecies of tropical gnatcatcher (P. plumbea), black-capped gnatcatcher (P. nigriceps), and "white-browed" gnatcatcher (P. plumbea bilieata) during its time as a separate species. It was most recently considered a subspecies of the white-lored gnatcatcher (P. albiloris) until a 2018 molecular study showed significant differences from all other gnatcatchers.
- 学名
- Polioptila albiventris
- 命名信息
- Lawrence, 1885
- 目
- Passeriformes
- 科
- Polioptilidae
- 属
- Polioptila
分布与栖息地
The Yucatan gnatcatcher is found only on the northern coast of Mexico's Yucatan Peninsula. Its primary habitat is arid coastal scrub, and it also occurs in low deciduous woodlands and coastal mangroves. Most observations are within 50 km (31 mi) of the ocean where the maximum elevation appears to be approximately 200 m (660 ft).
行为
No information on the Yucatan gnatcatcher's diet or feeding technique has been published, but in common with others of its genus, "its diet is presumed to consist largely of small invertebrates gleaned from foliage or captured with short sallies."<p>Though nothing has been published about the Yucatan gnatcatcher's breeding phenology, some information has been gleaned from publicly posted photographs. The nest is a small cup of plant fibers, built by both sexes, and placed in a small tree or shrub. Active nests were found in May and June and fledglings observed in June and July.<p>The Yucatan gnatcatcher has two songs, a low-pitched nasal one and a higher-pitched clearer one. Both are in this recording: [1].
照片
分布
鸟叫声
其他鸟类
Blue-tailed Hummingbird
Saucerottia cyanura
Medium-sized hummingbird of woodlands, plantations, and forest edges in tropical lowlands and foothills of southern Chiapas and northern Central America. Feeds at all levels at flowering trees and bushes, perching mainly at low to middle levels. Note the deep blue tail, purplish rump, and small rusty wing patch. Male is deep emerald green overall. Female is duller with grayish belly. The base of the lower bill is red on both sexes but often difficult to see.
Barred Long-tailed Cuckoo
Cercococcyx montanus
Rufous-brown, heavily barred cuckoo with an unusually long tail. There can be a wash of rufous on the throat and/or breast. Found in forest and thick woodland, including some miombo. Shy and retiring, and most easily found by voice. There are two main vocalizations; one is a long series of slurred “tseeeuw” calls which become more empatic. This sometimes leads into the second call type, which is a four-noted “toot tweet tow tweet.” Similar to other long-tailed cuckoos, but the adult is easily separated by the rufous barring on the upperparts.
White-headed Petrel
Pterodroma lessonii
A large gadfly petrel with a pale white head and a distinctive dark eye-patch. Back is pale gray with darker outer wings, creating an “M” shape on the back. Look for stout black bill and pinkish-colored feet. Breed on Antipodes and Auckland Islands in the New Zealand region and also on subantarctic Indian Ocean and Macquarie Islands. Forages between the subantarctic and Antarctic convergence zones. Three similar species: Soft-plumaged Petrel is smaller with gray-brown head and band on upper breast; Gray Petrel is larger with a smaller, darker head, a pale green bill, and a long neck; and pale morph Kermadec Petrel is smaller, lacks an eye patch, has darker upperparts, and shows white patches under the wing.
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。