The white-tailed sabrewing is a medium-sized hummingbird found in Central America and western South America. With its vibrant green plumage, distinctive white-tipped tail, and curved bill, this species is unmistakable among hummingbirds.
Adult white-tailed sabrewings reach about 8-9 centimeters in length and weigh 5-7 grams. As their name suggests, the most distinctive feature of these hummingbirds is the white tips on their outer tail feathers. The rest of the plumage is primarily vibrant emerald green on the upperparts and whiter on the underparts. The bill is fairly long, thin, and distinctly curved. The legs and feet are small and blackish.
Males and females look alike, although the emerald colors may be slightly duller on females. Immature birds have buffy edges to the green feathers. The white tail tips help distinguish sabrewings from other similar hummingbird species in their range.
White-tailed sabrewings are found from southern Mexico through Guatemala, El Salvador, Honduras, Nicaragua, Costa Rica and Panama. Their range extends into parts of Colombia, Venezuela, Ecuador, Peru and Bolivia in northwestern South America.
They reside in tropical and subtropical forests, woodlands, and shrublands, mainly at lower elevations up to around 5000 feet. However, they may venture higher into mountain forests during the warmer months when flowers are in bloom.
Diet and Feeding
Like all hummingbirds, white-tailed sabrewings have specialized diets consisting of nectar, tree sap, and small insects. Their long curved bills allow them to access nectar from tubular flowers. Some favorite nectar sources are flowers from the Heliconia genus as well as psuedobananas.
These agile hummingbirds can hover in midair while feeding and even maintain their position while winds blow them backwards, a feat requiring immense energy output. Their fast metabolism requires them to consume more than their weight in nectar each day.
In addition to nectar, sabrewings will supplement their diet with tree sap and small insects including mosquitoes, spiders, aphids, and gnats. The extra protein boost helps maintain their high metabolisms.
White-tailed sabrewings exhibit some interesting behaviors both in the way they feed and interact. As territorial birds, they are aggressive towards other hummingbirds that encroach on their feeding areas. They will vocalize warnings, perform display dives and even physically chase intruders away.
When feeding, sabrewings show a behavior called trap-lining where they repeatedly visit favorite nectar sources in a set sequence or “trap line.” This allows them to most efficiently exploit the nectar availability in their territory.
Sabrewings also exhibit an intriguing behavior where individuals will follow groups of army ants swarming through the forest. When insects and small animals flee from the advancing ants, the hummingbirds opportunistically pick them off. This gives them access to extra protein stirred up by the ant swarms.
Reproduction and Nesting
In Central America, the breeding season for white-tailed sabrewings typically runs from January through August. However, timing can vary by region and elevation. Males will perform elaborate courtship displays, flying back and forth in u-shaped patterns to impress females.
Once paired, the female constructs a small cup-shaped nest out of plant down, spider webs and lichens. She attaches it to a tree branch, often overhanging a stream. The eggs are tiny, about the size of a coffee bean. She usually lays two eggs and incubates them for 14-19 days.
The chicks hatch out blind, featherless, and highly vulnerable. The female cares for them, feeding them regurgitated nectar and insects. They grow and fledge in about 20-26 days from hatching. The father does not participate in rearing the young.
Currently, white-tailed sabrewings are listed as a species of Least Concern by the IUCN. While some localized declines have occurred, their overall population remains steady throughout most of their range. Destruction of rainforest habitats is one concern for the future.
However, they readily adapt to gardens, parks, and degraded woodland areas. This adaptability should help them fare better than some other tropical hummingbirds. Maintaining protected reserves and habitats will benefit sabrewings and countless other rainforest species.
With their glittering emerald plumage, curved bills, and energetically territorial behavior, the white-tailed sabrewing aptly reflects the dynamism of hummingbirds. While small, they play an integral role as pollinators in tropical American ecosystems. Their unique adaptations allow them to thrive and fully exploit both flowering plants and insect populations. As striking members of the diverse hummingbird family, sabrewings provide an excellent representation of the specialized traits and behaviors found across this captivating group of birds. Their continued preservation provides an opportunity to better understand the ecology and evolution of hummingbird species worldwide.