The Black-breasted Hillstar (Oreotrochilus melanogaster) is a species of hummingbird found in the Andes mountains of South America. With its dark, velvety plumage and glittering crown, this small bird has captivated observers for centuries.
The black-breasted hillstar is a relatively small hummingbird, measuring only 8-10 centimeters in length and weighing 5-7 grams. The male has primarily black plumage on its head, back, wings and tail. Its underside is white from its chin down to its legs. The female hillstar has more gray-brown plumage overall, though retains the black tail. Both sexes have an iridescent purple-blue crown atop their heads. The long bill of the black-breasted hillstar is straight and black.
Males have a bright white spot behind their eyes, while females have white streaks along the sides of their throats. Juveniles resemble adult females but with more gray-brown plumage and less vibrant crowns. The hillstar’s wings are long and pointed, beating up to 15 times per second to enable the bird’s specialized hovering flight. The black-breasted hillstar’s tiny feet have distinct middle and outer toes that provide grip when perching.
Habitat and Range
The black-breasted hillstar lives in the high Andes mountains at elevations between 3000-5000 meters. Its range extends from central Peru to northern Chile and Argentina. These hummingbirds are found in alpine scrublands and grasslands, rocky outcroppings, and along mountain streams. They tend to avoid dense, forested areas.
Hillstars prefer the marginal zones between habitat types at this altitude where flowering plants, grasses, mosses and lichens meet bare ground. This selective habitat provides the food resources these tiny birds need as well as lookout perches and nesting sites. The hillstar’s metabolic rate is extremely high to support hovering flight in the thin, cold Andean air.
To meet their high energy needs, black-breasted hillstars feed on nectar from tube-shaped flowers of alpine plants and small arthropods. Favored nectar sources include species in the genera Alstroemeria, Barnadesia, Cantua, and Collaea. The long, specialized beak allows the birds to delve into flowers other pollinators can’t access. Hillstars use their extensible tongues to lap up the nectar while hovering in front of flowers.
When collecting insects from crevices in rocks or clumps of vegetation, the hillstar contorts its body in aerobatic maneuvers. Prey includes flies, beetles, leafhoppers, caterpillars and spiders. The hillstar supplements its diet with pollen and moss sporophytes scraped off using its lower mandible.
The breeding season for the black-breasted hillstar coincides with the austral spring and summer from October to February. Males perform elaborate courtship flights to attract females, flying in wide arcs while calling loudly. They may also puff up their iridescent crown feathers.
Once paired, the female hillstar builds a tiny cup nest out of moss, straw and feathers on a vertical surface such as a rock wall or cliff face. She lines the inner nest with soft plant down. The female lays just two tiny white eggs and incubates them alone for about 16 days. Both parents feed the chicks with regurgitated food. The young fledge in just 3 weeks, remarkably fast for such small birds.
The black-breasted hillstar has a relatively localized range but remains fairly common within that range. Its high Andean habitat has limited human development or agriculture. The IUCN Red List categorizes this species as Least Concern. However, it does face some threats from mining activities and habitat degradation from overgrazing by livestock introduced into its native alpine ecosystems. Climate change may also shrink the extent of paramo vegetation favored by this species. Expanding protected areas around key hillstar breeding habitats can help conserve its populations into the future.
Several key adaptations allow the tiny black-breasted hillstar to survive in the harsh conditions of the high Andes:
– Specialized hemoglobin to extract oxygen efficiently from thin, cold air
– Dense, insulation plumage to retain body heat
– High metabolic rate and rapid heart rate to generate energy for hovering in thin air
– Excellent eyesight and maneuverability when foraging
– Ability to enter torpor to conserve energy overnight
– Long, specialized beak and tongue for drinking nectar from flowers
– Excellent grip provided by zygodactyl feet when perching
The black-breasted hillstar has long captivated people living in the Andes due to its striking beauty and aerial agility. Ancient Incan civilizations featured the hummingbird in their artwork and imagery, believing it possessed magical qualities. Many legends center on its status as a messenger or transformer.
The hillstar remains an iconic Andean bird, widely recognized as a symbol of delicate grace and speed by the people of countries such as Peru, Bolivia and Chile. Its image continues to be used in indigenous textiles, ceramics and motifs. While many hummingbirds have fascinated cultures throughout the Americas, the Andean hillstar holds a special place in the traditions of upland South America.
The dazzling black-breasted hillstar has adapted in many unique ways to thrive in the windswept, high elevation ecosystems of the Andes. Its specialized feeding behaviors and hovering flight make it a wonder to observe as it tirelessly darts among alpine flowers. While human activities have impacted some of its habitats, expanded conservation measures seem likely to protect significant populations of this beloved high-altitude pollinator into the future. The hillstar will continue to delight bird enthusiasts lucky enough to catch a glimpse of its sparkling beauty against the dramatic backdrop of South America’s most famous mountain range.