White-chested Emerald
Chrysuronia brevirostris
Small hummingbird with short, black bill and completely white underparts; found in savannas, dry forests, and disturbed habitats. Hovers at flowers like other hummingbirds. Males sing a hard, rattling trill from exposed perches beneath forest canopy. Most similar to Plain-bellied and Versicolored Emeralds, but has shorter, entirely black bill; where these species occur together, White-chested may not be safely separable from them if not seen well.
识别特征
The white-chested emerald is 9 to 10 cm (3.5 to 3.9 in) long. Males weigh about 4.6 g (0.16 oz) and females 4.4 g (0.16 oz). Adults of both sexes of all subspecies have a short, straight, blackish bill and the sexes are almost alike in plumage. The nominate subspecies has iridescent turquoise-green crown and cheeks and shining bronze-green upperparts that become coppery on the rump. Its central tail feathers are coppery and the outer ones bronze to copperish with blackish bars near the end of their underside. Its underside from throat to belly is white with bronze-green sides and flanks. Its undertail coverts are golden-green with white edges. The female differs from the male only by having grayish tips on the outer tail feathers. Juveniles resemble adult females with a yellowish to reddish base on their mandible.<p>Subspecies C. b. chionopectus is significantly larger than the other two subspecies but has the same plumage as the nominate. C. b. orienticola is similar to the nominate but has darker, more bronze colored, upperparts and flanks.
分类信息
The white-chested emerald's taxonomic history is complex. The species was previously known in succession as Amazilia chionopectus, Agyrtria brevirostris, and Amazilia brevirostris. A molecular phylogenetic study published in 2014 found that Amazilia was polyphyletic. In the revised classification to create monophyletic genera, the white-chested emerald was moved by most taxonomic systems to Chrysuronia. However, BirdLife International's Handbook of the Birds of the World retains it in Amazilia. <p>The white-chested emerald has three subspecies, the nominate C. b. brevirostris, C. b. chionopectus, and C. b. orienticola.
- 学名
- Chrysuronia brevirostris
- 命名信息
- (Lesson, RP, 1829)
- 目
- Apodiformes
- 科
- Trochilidae
- 属
- Chrysuronia
分布与栖息地
The nominate subspecies of white-chested emerald is the most widespread. It is found in eastern Venezuela, Guyana, Suriname, and extreme northern Brazil's Roraima state. C. b. chionopectus occurs only on Trinidad and C. b. orienticola only in coastal French Guiana. The species inhabits a variety of landscapes including rainforest; semi-deciduous, gallery, and secondary forests; scrublands; savanna; and some cultivated areas. C. b. chionopectus favors more open landscapes including cacao plantations. There are very few specimens or sightings of C. b. orienticola, and all are from coastal areas.
- 迁徙
- Resident species
行为
Most populations of white-chested emerald are thought to be sedentary but data are lacking.<p>The white-chested emerald forages for nectar at a variety of flowering plants and trees; species in at least nine families are known to be sources. In addition to nectar it feeds on insects captured by hawking from a perch or by gleaning from vegetation.<p>The white-chested emerald's breeding season includes at least December to April. It makes a cup nest of plant fibers with lichen on the outside and typically places it on a horizontal branch between 1 and 7 m (3 and 20 ft) above the ground. The female incubates the clutch of two eggs but the period is not known; fledging occurs about 20 days after hatch.<p>The white-chested emerald's song is variable but always "nasal and squeaky". Some typical phrases are described as "tsri-lee … tsri-lee ... tsri-lee", "tee-tink-tink-tink .. tsee-tink ... tee-tink-tink-tink … tsee-tink ...", or "teee-tjitjitjitjitji ..... teee-tjitjitjitjitji...".
保护状况
- 种群趋势
- stable
照片
分布
鸟叫声
其他鸟类
Black Scoter
Melanitta americana
Plump diving duck, typically seen in flocks in coastal areas. Males are completely black with bright orange knob on the bill. Females are brown overall with pale cheek and contrasting dark cap. Note potbellied shape and rounded head in flight. Typically coastal, but migrates over land especially in the Northeast U.S. Often gathers in tight flocks. Dives frequently, feeding on aquatic invertebrates. Breeds on ponds in Arctic tundra.
Bay-vented Cotinga
Doliornis sclateri
Uncommon cotinga found only in very high-elevation forest near treeline in the eastern Andes of central Peru. Adult plumage is gray with a tan breast and belly and a chestnut vent. Male has a black cap and a red crest that is usually hidden. Female lacks the crest and has only a little black on the crown. Juvenile is mostly brown but has the chestnut vent. Often perches up on an exposed branch. Typical call is a short, metallic rasp given at long intervals.
Rufous-tailed Robin
Larvivora sibilans
Combination of strongly scaled breast, rufous tail, and round-headed appearance distinguish this species from others in its range. Small and skulky, sticking to dense shrubbery and shorter trees in its forest breeding grounds, where it favors dense, moist growth in lowland broadleaf forests. Often bolder on migration, emerging into forest edges and gardens. Song is distinctive, a long, wet-sounding descending trill.
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。