The Pale-tailed barbthroat (Threnetes niger) is a small hummingbird found in tropical regions of South America. With an average body length of 7-8 cm and weight of 2-3 grams, it is a tiny bird with a long, slightly decurved black bill and relatively short wings. The male has a brightly colored throat patch that can appear yellow, orange or red depending on the angle. This iridescent gorget contrasts sharply with the bird’s otherwise dull plumage of olive green above and gray below. The female lacks the flashy throat patch and is even drabber in appearance.
The pale-tailed barbthroat is found in the lowland tropical rainforests on the eastern side of the Andes in South America. Its range extends from Venezuela and the Guianas in the north down through Brazil, Peru, Bolivia and Paraguay. It occupies the mid and lower levels of the rainforest, frequenting forest edges and second growth areas. The pale-tailed barbthroat can be found visiting flowers and feeding on nectar from understory herbs, shrubs and small trees. It uses its specialized long bill to probe into flowers. Like other hummingbirds, it can beat its wings up to 70 times per second, allowing it to hover in place while feeding.
This species builds a small cup-shaped nest out of plant fibers bonded together with spider silk. The female lays two tiny white eggs in the nest, which is situated on a low branch, vine or fern. She alone incubates the eggs, which hatch after 15-19 days. Once hatched, the chicks are fed on regurgitated nectar and insects by the female. They fledge within 20-26 days, after which they quickly become independent.
Pale-tailed barbthroats are solitary and territorial, with the male defending flower-rich feeding sites from other members of the same species. They are aggressive toward other hummingbird species that try to feed in their territory as well, chasing them away with fast aerial pursuits. Vocalizations include sharp chip notes used in territorial displays.
As with many other hummingbird species, the pale-tailed barbthroat’s populations appear to be declining. Habitat loss from deforestation is the primary threat facing this species across its range. Lowland tropical rainforests continue to be logged and converted to agricultural land at alarming rates in South America. The pale-tailed barbthroat is not currently considered threatened, but its reliance on pristine rainforest habitat makes it vulnerable to further losses.
Conservation efforts aimed at preserving intact rainforest habitat will benefit the pale-tailed barbthroat. Strict legal protections on remaining old growth tropical forest areas are needed to safeguard essential breeding and feeding grounds. Sustainable forestry practices and agroforestry can also help provide habitat in areas where some human disturbance has already occurred. Ecotourism projects may assist by giving local communities incentive to maintain rainforest areas due to an interest in preserving wildlife for visiting birders and naturalists. Continued monitoring of pale-tailed barbthroat populations will be necessary to detect any declines that may warrant higher threat status for the species in the future.
In aviculture, the pale-tailed barbthroat is considered a specialty hummingbird that is infrequently kept and bred in captivity, as it can be delicate and sensitive to husbandry conditions. Those experienced aviculturalists who have worked with the species recommend planted vivariums that closely simulate the bird’s natural rainforest environment. A diet of specialized commercial nectar mixes, fruit flies, termites and other tiny insects must be provided. Breeding success has been limited, indicating there are still unknown factors regardingproper captive care of the pale-tailed barbthroat. Field studies focused on the natural history and ecology of wild pale-tailed barbthroats are needed to inform best practices for any captive management.
The pale-tailed barbthroat remains one of South America’s more mysterious and little-known hummingbirds due to its inaccessible rainforest habitat. As deforestation increasingly encroaches on its range, hopefully growing eco-tourism and conservation initiatives can protect vital habitat and stabilize populations of this species. Though small, the pale-tailed barbthroat serves as an important pollinator for rainforest plant communities. Ensuring its survival means protecting an intricate web of ecological relationships that sustain the magnificent biodiversity of tropical forests. With careful management of wilderness resources and regulation of logging activities, the pale-tailed barbthroat will continue to flourish, representing a fragile beauty in one of the world’s most complex ecosystems.