The Glittering-bellied Emerald (*Chlorostilbon lucidus*) is a dazzling hummingbird found primarily in eastern South America, from Brazil to Argentina. True to its name, this small bird boasts a brilliant, iridescent green belly that shimmers in the sunlight, contrasting with its coppery-bronze back and forked, dark blue tail. Males are especially striking with a vibrant blue throat and a short, straight black bill, while females are slightly duller with a white stripe behind the eye. A unique characteristic of this species is its remarkable territorial aggression, often fearlessly chasing away much larger birds from its nectar-rich flower patches. Its rapid, buzzing wingbeats and ability to hover with pinpoint precision make it a living jewel of tropical gardens and forest edges.

Faits amusants

Despite its name, the Glittering-bellied Emerald’s iridescent belly actually appears black in most lighting conditions, flashing brilliant green only when the sun hits at the perfect angle. Males perform a bizarre courtship display where they hover in front of the female and rapidly flick their forked tail feathers, creating a distinct buzzing sound like a tiny zipper. Unlike many hummingbirds that aggressively chase off rivals, this species has been observed tolerating other emeralds feeding nearby in flowering trees, suggesting a surprisingly cooperative streak during non-breeding seasons. Its tongue is tipped with hair-like structures called lamellae that trap nectar with such efficiency that it can drain a flower in under three seconds.

Habitats et répartition

The Glittering-bellied Emerald is found across a broad swath of central and eastern South America, ranging from eastern Bolivia and central Brazil south through Paraguay and Uruguay to northeastern Argentina. It inhabits a variety of open and semi-open environments, including savannas, cerrado woodlands, gallery forests, scrubby pastures, and urban gardens. It is also common in the Atlantic Forest’s edges and clearings, as well as in dry thorn forests and coastal restinga vegetation, showing a preference for areas with scattered trees and flowering shrubs.

Comportements & Reproduction

The Glittering-bellied Emerald is generally solitary outside of breeding, with males defending feeding territories rather than forming pair bonds. Courtship involves the male performing a distinctive U-shaped dive display in front of a perched female, accompanied by high-pitched vocalizations, to secure mating rights. After copulation, the male plays no role in nesting or parental care. The female alone constructs a small cup-shaped nest using plant down and spider webs, often on a horizontal branch, where she lays two white eggs. Incubation lasts about 13–15 days, and the chicks fledge after roughly 20–22 days. A unique reproductive strategy is the female’s ability to lay a second clutch while still feeding fledglings from the first brood, maximizing reproductive output in favorable conditions.

Alimentation

The Glittering-bellied Emerald is a nectarivorous hummingbird, feeding primarily on the high-energy nectar from a variety of tubular flowers, including those of the genus *Erythrina*, *Jacaranda*, and *Hamelia*. An interesting fact about its diet is that it supplements this sugary liquid with small arthropods like spiders, gnats, and flies, which it catches by hawking (snatching from the air) or gleaning from leaves and spider webs, providing essential proteins and fats for growth and reproduction. Despite its small size, it must consume more than its own body weight in nectar daily, and it exhibits a unique feeding strategy called "trap-lining," where it visits a specific circuit of flowers in a predictable sequence to maximize efficiency.

Couleurs

The male Glittering-bellied Emerald has a brilliant, iridescent golden-green belly and throat, with a deep blue-purple tail and a bright red bill tipped black. The female is duller, with a white underside and throat, a green back, and a white stripe behind the eye. Both sexes have no special camouflage, but their shimmering colors help them blend into sunlit foliage.