Esmeralda Colifina
Narrow-tailed Emerald
Chlorostilbon stenurus
Song
Narrow-tailed Emerald
Appearance: The Narrow-tailed Emerald is a small hummingbird, about 7.6 cm long and around 3–3.5 g. The male is mostly brilliant metallic green, with shining green upperparts and iridescent green underparts. Its tail is dark green, forked, and very narrow, with the outer tail feathers reduced and pointed, giving the species its “narrow-tailed” name. The bill is short, straight, and black. The female is duller: green above, paler whitish below, with a slightly decurved bill, dusky face, and white-tipped outer tail feathers.
Habitat: It inhabits humid montane forest, forest borders, secondary growth, shrubland, and degraded former forest. It often uses fairly open or disturbed habitats, especially shrubby edges and regenerating vegetation. It is mainly a montane species, usually found between about 1,000 and 2,300 m elevation.
Behavior: This hummingbird usually forages low to middle levels in vegetation. It feeds on nectar by trap-lining, meaning it visits a regular circuit of flowers rather than defending only one flower patch. It visits plants such as Ericaceae, Rubiaceae, Heliconiaceae, Gesneriaceae, and Inga. It also catches small insects, often by flying out from a perch. It is considered generally sedentary, although it may make local seasonal elevational movements.
Breeding: The breeding season is reported mainly from September to November. The female builds a small cup nest made of moss, with lichen on the outside for camouflage. The nest is usually placed in a shrub or small tree about 1–2 m above the ground. The clutch is typically two eggs; incubation is about 15–16 days, and young leave the nest after about 20 days.
Conservation Status: The Narrow-tailed Emerald is listed as Least Concern
MALE
FEMALE
Distribution
It is found mainly in the northeastern Andes, especially the Eastern Cordillera. The nominate subspecies Chlorostilbon (stenurus) stenurus occurs from the Andes of Colombia in the border with Venezuela.
Taxonomy
The Narrow-tailed Emerald (Chlorostilbon stenurus)
- Kingdom: Animalia
- Phylum: Chordata
- Class: Aves (Birds)
- Order: Caprimulgiformes
- Family: Trochilidae
- Genus: Chlorostilbon
- Species: stenurus
Vocalization
A recent Macaulay Library record from nearby Mérida, Venezuela, describes the voice as a very high-pitched, sharp vocalization.
The Narrow-tailed Emerald (Chlorostilbon stenurus) has poorly documented calls.
Its most likely call type is a short, very high-pitched contact note, probably a thin “tsip,” “tseep,” or “sit.” This would be used while the bird is perched, feeding, or moving through shrubs and forest edges.
A second likely vocalization is a rapid repeated call, such as “tsip-tsip-tsip.” This would probably be heard during close interactions with other hummingbirds, especially around flowers or feeding areas.
It may also give brief flight calls while moving between flowers or perches. These are probably short, sharp notes similar to the contact call, but given in flight.
