The Narrow-tailed Emerald Hummingbird (Chlorostilbon angustipennis) is a small hummingbird found in northern Colombia and western Venezuela. With an average body length of 7-8 cm and weight of 2-3 grams, it is one of the smaller hummingbird species in South America. Its name refers to its distinctive long, narrow tail feathers.
Description
The male narrow-tailed emerald has vibrant emerald green upperparts from its head to tail, with a shiny emerald gorget (throat patch) and white underparts. The female is slightly duller, with more greyish-green upperparts and a whitish throat and belly. As the name suggests, both sexes have a long, narrow tail that can appear almost spike-like when spread open. The tail feathers are dark purplish-black. The bill of this hummingbird is thin, straight and black. Juveniles resemble adult females but have buffy edges to their plumage.
Distribution and Habitat
This hummingbird is endemic to Colombia and Venezuela. In Colombia, it is found along the Caribbean coast and the lower ranges of the Santa Marta Mountains. Its range extends from the Guajira Peninsula in the north to the Magdalena Valley in the south. In Venezuela, it occupies coastal regions near the Colombia border.
The narrow-tailed emerald inhabits dry forests, scrublands, and savannas, particularly favoring forest edges, clearings, and gardens. It is found from sea level up to elevations of 1000 m. It prefers hot, arid environments with flowering plants and scrubby vegetation.
Behavior and Ecology
Like most hummingbirds, the narrow-tailed emerald feeds on nectar from flowers using its long extendable tongue. It favors flowers of the families Cactaceae, Agavaceae, and Bromeliaceae. It also eats small insects to obtain protein.
The males are territorial, using vocalizations and display flights to defend rich flower feeding areas. Their display consists of flying in an oval U-shaped pattern less than 1 m above the ground.
Breeding takes place in the dry season between December to April. The female builds a small cup-shaped nest out of plant fibers and spider webs, attached to a branch 2-4 m above ground. She lays two tiny white eggs and incubates them alone for 15-19 days. The chicks hatch with their eyes closed and no feathers. They are fed regurgitated insects and nectar by the female and fledge in about 20-28 days.
Conservation Status
The narrow-tailed emerald hummingbird has a wide distribution and large population, estimated at 50,000 to 500,000 individuals. Its population appears to be stable and it is evaluated as Least Concern on the IUCN Red List. Major threats include habitat loss from agriculture, grazing, and development. Climate change and drought may also impact its arid habitat in the future. As it prefers scrubby vegetation, maintaining areas of natural brush and shrubs will help provide habitat for this species.
Interesting Facts
– The narrow-tailed emerald gets its name from its long, spike-like tail feathers that can measure up to 4 cm in length. When the tail is closed, the feathers overlap to form a narrow, pointed shape.
– Male narrow-tailed emeralds make a high-pitched repetitive vocalization sounding like “seep-seep” which is thought to be used in territorial displays.
– This species is not a forest interior hummingbird. It prefers open, arid environments and is found at forest edges and clearings where it can hawk insects.
– It has a fast, direct flight and is able to hover in place while feeding on flowers. The wings beat around 50 times per second.
– Narrow-tailed emeralds have been reported visiting more than 25 species of plants for nectar, though they prefer flowers of the aloe and agave families.
– The species was first described by French ornithologist Charles Lucien Bonaparte in 1850. For many years it was considered a subspecies of the white-tailed emerald until given full species status in 1999.
In summary, the narrow-tailed emerald is a small, vibrant hummingbird adapted to the arid scrublands of northern Colombia and Venezuela. Its specialized habitat preferences and long, narrow tail feathers make it a unique South American hummingbird. Maintaining its preferreddry forest and scrub habitat will be key to ensuring the continued survival of this species.