The Green-tailed Emerald (Chlorostilbon mellisugus) is a small hummingbird found in tropical Central and South America. With its vibrant green plumage and long forked tail, this species is one of the most striking and easily recognizable hummingbirds.
The adult male Green-tailed Emerald has mostly bright metallic green plumage covering its head, back, wing coverts and tail. The throat is glittering golden green while the chest and belly are white. As the name suggests, the tail is long and deeply forked, with each fork extending 3-4 cm beyond the rest of the tail. The tail covers are bright emerald green. The bill of the Green-tailed Emerald is long, straight and black. The eyes are dark brown. Females are similar to males but have white spotting on the throat and chest. Juveniles resemble adult females but with buffy edges to the plumage.
Green-tailed Emeralds are relatively small, measuring 9-10 cm long and weighing around 4-5 grams. However, the elongated tail makes the bird appear somewhat larger at first glance. In fact, over half of its total length is made up by its tail. The wings are small and narrow as is characteristic of hummingbirds.
Distribution and Habitat
The Green-tailed Emerald has a wide distribution across Central and South America. Its range extends from southern Mexico through Guatemala, Belize, El Salvador, Honduras, Nicaragua, Costa Rica and Panama. In South America, it is found in Colombia, Venezuela, Ecuador, Peru, Bolivia, Brazil, the Guianas and many Caribbean islands including Trinidad and Tobago.
This species inhabits a range of tropical environments including rainforests, woodlands, plantations, gardens and mangroves. It has a preference for edges and openings in forests as well as secondary growth. The Green-tailed Emerald is mostly found in lowlands and foothills up to 1000 m elevation but occasionally occurs as high as 1500 m in some areas.
Diet and Feeding
Like all hummingbirds, the Green-tailed Emerald feeds on nectar extracted from flowers using its long extendable tongue. It favors flowers with sturdy corollas that can support its weight as it hovers in front of the blossom. Some favorite nectar sources include flowers from shrubs and small trees such as Inga, Erythrina, Calliandra and various Heliconia species. The Green-tailed Emerald uses its slender bill to pierce the base of the corolla to access the nectar.
This species is also adept at hawking small insects in flight, which provide an essential source of protein and nutrients. It plucks tiny insects such as mosquitoes, flies and spiders out of the air with great dexterity, often while hovering.
The breeding season of the Green-tailed Emerald coincides with the rainy season across most of its range. Courtship displays by the male involve aerial flights and dives to impress potential mates. Once paired, the female builds a small cup-shaped nest out of plant down, fibers and spider silk on the underside of large leaves, often overhanging a stream. She lays just two tiny white eggs. The female alone incubates the eggs for about 16-19 days. Once hatched, the chicks are fed regurgitated food by the female and fledge in around 20-26 days, but may continue to be fed by the female for some time after leaving the nest.
The Green-tailed Emerald has an extremely large range estimated at over 4 million square kilometers. The global population also seems to be large and stable based on observations. For these reasons, the species is evaluated as Least Concern on the IUCN Red List of Threatened Species. However, habitat destruction in some regions may be impacting local populations. Maintaining undisturbed primary rainforest habitat is important for the long-term conservation of this and other hummingbird species.
– The elongated tail of the male Green-tailed Emerald accounts for over 60% of its total body length. This is the longest tail relative to body size of any hummingbird species. The reason for this extravagant ornamentation is likely to enhance agility and courtship displays.
– Green-tailed Emeralds utilize a wide variety of flowering plants and are important pollinators for many tropical plant species. Their ability to hover in front of flowers while feeding allows them to access nectar from specialized bird-pollinated flowers.
– Males are highly territorial and use their metallic green plumage to dazzle rivals and attract mates. The iridescent feathers refract light into vivid flashes of color. Males may also produce buzzing and clicking sounds with their tail feathers during courtship displays.
– This hummingbird gets its name from the brilliant emerald green colors of the male. But females and juveniles are much duller with mostly yellowish-green plumage (except for the tail). This pronounced sexual dimorphism is quite unusual among hummingbird species.
– Taxonomically, the Green-tailed Emerald is placed in the large hummingbird genus Chlorostilbon along with its North American cousin the Ruby-throated Hummingbird. There are around 12 recognized species in this genus occurring in the New World tropics.
In summary, the striking and aptly named Green-tailed Emerald is a tropical jewel of Central and South America’s hummingbird diversity. With its unmistakable long forked tail and vibrant plumage, this charismatic species stands out among its relatives. Though small, it plays an important role as a pollinator for rainforest plants. As deforestation threatens much equatorial habitat, preserving expanses of old growth forest will be key to ensuring this emerald hummingbird continues to glisten over the jungles of the future.