Violet-tailed Sylph

Hummingbird Information

Violet-tailed Sylph, Aglaiocercus coelestis


Violet-tailed Sylph, Aglaiocercus coelestisThe Violet-tailed Sylph (Aglaiocercus coelestis) is a South American hummingbird that occurs naturally in Colombia and Ecuador at elevations from 300 to 2100 meters; however mostly above 900 meters.

These solitary birds typically remain low inside forest areas, close to small clumps of flowers.


Subspecies and Distribution:

  • Aglaiocercus coelestis coelestis - Nominate Race (Gould, 1861)
    • Range: Along the Pacific slope of the west Andes of both Colombia and north and central Ecuador

  • Aglaiocercus coelestis aethereus (Chapman, 1925)
    • Range: Southwest Ecuador, south from Zaruma


Males are around 18 - 21 cm (~7 inches) and females about 9.5 - 9.7 cm (~3.8 inches) long - including their long tail. They weigh around 4.6 – 5.2 g.

The male has a long blue-violet tail. The rest of his plumage is mostly an iridescent green, with orangey-copper coloration on the throat and upper chest, and a blue crown.

The female is also mostly green. She has a blue crown, a rusty-orange abdomen, as well as a white upper chest band and tail tips,

In some instances, females lack the white upper breast band and then are easily confused with Long-tailed Sylph - however, an ID can be made by the color of their crown, which is blue in the Violet-tailed Sylph and green in the Long-tailed Sylph.


Violet-tailed Sylph, Aglaiocercus coelestisNesting / Breeding

Hummingbirds are solitary in all aspects of life other than breeding; and the male's only involvement in the reproductive process is the actual mating with the female. They neither live nor migrate in flocks; and there is no pair bond for this species. Males court females by flying in a u-shaped pattern in front of them. He will separate from the female immediately after copulation. One male may mate with several females. In all likelihood, the female will also mate with several males. The males do not participate in choosing the nest location, building the nest or raising the chicks.

The nest is a suspended ball of moss that is fastened to leafy twigs with a side entrance. The average clutch consists of one white egg, which she incubates alone, while the male defends his territory and the flowers he feeds on. The young are born blind, immobile and without any down.

The female alone protects and feeds the chicks with regurgitated food (mostly partially-digested insects since nectar is an insufficient source of protein for the growing chicks). The female pushes the food down the chicks' throats with her long bill directly into their stomachs.

As is the case with other hummingbird species, the chicks are brooded only the first week or two, and left alone even on cooler nights after about 12 days - probably due to the small nest size. The chicks leave the nest when they are about 20 days old.


Violet tailed sylphDiet / Feeding

The Violet-tailed Sylphs primarily feed on nectar taken from a variety of brightly colored, scented small flowers of trees, herbs, shrubs and epiphytes. They favor flowers with the highest sugar content (often red-colored and tubular-shaped) and seek out, and aggressively protect, those areas containing flowers with high energy nectar.They use their long, extendible, straw-like tongues to retrieve the nectar while hovering with their tails cocked upward as they are licking at the nectar up to 13 times per second. Sometimes they may be seen hanging on the flower while feeding.

Many native and cultivated plants on whose flowers these birds feed heavily rely on them for pollination. The mostly tubular-shaped flowers actually exclude most bees and butterflies from feeding on them and, subsequently, from pollinating the plants.

They may also visit local hummingbird feeders for some sugar water, or drink out of bird baths or water fountains where they will either hover and sip water as it runs over the edge; or they will perch on the edge and drink - like all the other birds; however, they only remain still for a short moment.

They also take some small spiders and insects - important sources of protein particularly needed during the breeding season to ensure the proper development of their young. Insects are often caught in flight (hawking); snatched off leaves or branches, or are taken from spider webs. A nesting female can capture up to 2,000 insects a day.

Males establish feeding territories, where they aggressively chase away other males as well as large insects - such as bumblebees and hawk moths - that want to feed in their territory. They use aerial flights and intimidating displays to defend their territories.

Violet-tailed Sylph, Aglaiocercus coelestis

Metabolism and Survival and Flight Adaptions - Amazing Facts


Calls / Vocalizations

Its call is described as a rapid, double-sounding tez-it.

Species Research by Sibylle Johnson


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