The dusky starfrontlet (Coeligena orina) is a small hummingbird found in the Andes mountains of South America. With an average body length of only 8-9 cm and weighing 5-7 grams, it is one of the smallest hummingbirds in the world. Despite its tiny size, the dusky starfrontlet exhibits an incredible array of adaptations that allow it to thrive in the harsh, high-altitude environments it inhabits.
Range and Habitat
The dusky starfrontlet has a relatively restricted range, occurring only in the Andes mountains of Colombia, Ecuador and northern Peru. It is found at elevations between 2500-3600 meters, inhabiting the elfin forests and paramo grasslands of the high Andes. These treeless habitats are characterized by low temperatures, frequent rain and mist, and intense winds. Few bird species are adapted to survive these conditions, but the dusky starfrontlet manages to eke out an existence in this inhospitable environment. It tends to prefer areas with an abundance of flowering plants, which provide the nectar that comprises the bulk of its diet.
Description and Identification
The dusky starfrontlet is aptly named for its distinctive plumage. The male has a velvety blue-black head, underparts and tail, contrasting sharply with its metallic bronze-green back and wings. A bright white stripe extends behind each eye. The bill is long, straight and black. The female is similar, but has gray undertail feathers and buffy streaks on the throat. Juveniles resemble the adult female.
In flight, the dusky starfrontlet can be identified by its small size, rapid wingbeats and slightly forked tail. The white eye streaks are also visible. It hovers frequently to feed on nectar from flowers. Its call is a high-pitched, squeaky “seet” sound.
The star-shaped feathers on the throat are thought to aid in heat retention in the cold mountain environments. This unique adaptation gives the species its common name.
Diet and Feeding
Like all hummingbirds, the dusky starfrontlet has a very fast metabolism. It feeds almost exclusively on nectar from flowering plants such as succulents, lupines, and red-hot pokers. It uses its specialized long bill and tongue to drink the nectar while hovering in front of flowers. The bill is perfectly adapted to the shape of the flowers from which it feeds.
The dusky starfrontlet supplements its diet with small insects such as gnats, flies, and spiders. It gleans these prey items from foliage or catches them in flight. The extra protein from insects is an important part of its energy requirements, especially during breeding season when energy demands are highest.
Living at such high altitudes requires an incredible array of specialized adaptations. One of the most vital is an increased oxygen carrying capacity. The dusky starfrontlet has proportionally larger lungs and heart relative to its body size compared to lowland bird species. This allows more efficient oxygen intake and circulation at high elevations where the air is thinner.
Dense, thick plumage provides insulation against freezing temperatures and winds. The nostrils are protected by feathers specialized for retaining heat.
Long wings and a short, rounded tail stabilize the bird while hovering in turbulent winds. Strong legs and feet allow it to tightly grip flowers and branches.
The dusky starfrontlet, like most hummingbirds, is solitary and territorial. Males establish breeding territories with plenty of flower resources which they aggressively defend from intruders. Females move through these territories seeking mates. Outside of the breeding season, they form loose flocks of hundreds of individuals that wander nomadically following the blooming of nectar plants.
Courtship displays involve the male hovering in front of the female and flying in dramatic vertical figures-of-eight or pendulum motions. If receptive, the female perches submissively with her tail feathers spread upward.
The nest is cup-shaped, woven from soft plant fibers and spider silk. It is attached to a vertical branch or tree fern. The female lays just two tiny white eggs. She alone incubates the eggs for about 16 days until they hatch.
The chicks are born helpless, featherless and with their eyes closed. The female cares for them entirely on her own, sheltering them under her wings at night or during cold snaps. She feeds them regurgitated nectar and insects. After 25-30 days, the chicks fledge and leave the nest. The female may then raise a second brood.
Threats and Conservation
While still relatively common, the dusky starfrontlet faces threats from habitat loss and climate change. Logging and land clearing destroys the elfin forest habitats this species depends on. Global warming causes upward shifts in vegetation zones, eliminating paramo habitat. Introduced grazing animals degrade fragile paramo vegetation.
Part of the dusky starfrontlet’s range lies within protected areas such as Ecuador’s Cayambe-Coca Ecological Reserve and Peru’s Huascaran National Park. But further habitat protection and limits on grazing are needed. Building corridors between isolated fragments can help the species move to more suitable habitat as climate shifts occur.
The IUCN Red List categorizes the dusky starfrontlet as a species of Least Concern. But more research and monitoring of populations are warranted to detect any declines that would necessitate stronger conservation actions. This unique and exquisite high-mountain jewel deserves protection in its fragile sky island habitats.
The dusky starfrontlet is a tiny hummingbird that has adapted to make a living in the demanding high Andes environment. It can survive freezing temperatures, howling winds and scarce oxygen thanks to modifications like dense plumage, enlarged heart and lungs, and strong claws. This species drinks nectar using a specialized long bill and tongue, and supplements its diet with small insects.
Males defend flower-rich territories, displaying dramatically to attract females. Females alone build the nest, incubate eggs and raise the young. Habitat loss and climate change pose threats. Protecting paramo habitat and creating corridors is vital for this species’ future survival. Though currently stable, more research and monitoring of dusky starfrontlet populations is warranted.