Black-bellied Hummingbird

The Black-bellied Hummingbird, known scientifically as Eupherusa nigriventris, is a diminutive avian jewel, measuring a mere 7 to 8 centimeters in length and tipping the scales at approximately 3.0 to 3.5 grams. The males of this species are distinguished by their eponymous black breast and belly, with a similarly shaded forehead and face. Their upperparts are predominantly bronze green, accented with narrow black edges on the crown feathers and a duller bronze on the uppertail coverts. The central tail feathers exhibit a dull black hue with a subtle bronze sheen, while the outer feathers are white. Females, on the other hand, display grayish white underparts and white undertail coverts, with metallic bronze green upperparts that transition to a more pronounced bronze on the uppertail coverts.

Identification Tips

When attempting to identify the Black-bellied Hummingbird, look for the male's distinctive black underparts and the female's grayish white underparts. Both sexes share the characteristic bronze green upperparts, but the male's black crown with narrow edges is a key feature. The white outer tail feathers are also a helpful marker for identification.

Habitat

This species favors the edges and interiors of humid montane forests, thriving at elevations ranging from 600 to 2,000 meters above sea level.

Distribution

The Black-bellied Hummingbird graces the Caribbean slope, with its range extending from Costa Rica into western Panama.

Behaviour

As a mostly year-round resident, the Black-bellied Hummingbird exhibits some seasonal movement, with individuals occasionally descending to lower elevations post-breeding. Males are known to defend flowering trees in the forest canopy, while females more commonly forage in the understory and at forest edges.

Song & Calls

The song of the Black-bellied Hummingbird is a high, thin, sputtering warble, often delivered from perches at forest gaps. Its calls include a sharp, high-pitched "tseep" or "peet," as well as a high, twittering sound during chases.

Breeding

Breeding season in Costa Rica typically spans from October to March, with some early starters in July. The breeding is timed with the flowering of canopy epiphytes and other plants. Females construct a cup nest from tree fern scales and spiderweb, adorned with moss and lichen, usually situated 2 to 4 meters above ground under a protective leaf. The clutch consists of two eggs, though incubation and fledging periods remain undocumented.

Diet and Feeding

The Black-bellied Hummingbird's diet consists of nectar from various sources, including Inga and Pithecellobium trees, epiphytes like Ericaceae, Columnea, Elleanthus, and Norantea, as well as understory plants such as Psychotria, Witheringia, and Besleria. It has shown a preference for shorter flower types. Additionally, it supplements its diet with small arthropods.

Conservation status

The IUCN has classified the Black-bellied Hummingbird as Least Concern. Despite its relatively small range, there are no immediate threats identified, and in Costa Rica, it is considered "uncommon to locally abundant." However, it could potentially be vulnerable to habitat loss.