The Buff-winged Starfrontlet (Coeligena lutetiae) is a small hummingbird found exclusively in the Andes Mountains of northern South America. Measuring just 8-9 centimeters in length and weighing 4-5 grams, it is one of the smallest hummingbird species in the world. Despite its tiny size, the Buff-winged Starfrontlet exhibits some remarkable adaptations that allow it to thrive in the cold, high-altitude cloud forests it inhabits between 2500-3700 meters above sea level.
Physical Description
The most distinguishing feature of the Buff-winged Starfrontlet is the buff-colored patches on the undersides of the male’s wings and tail. The plumage on the upperparts and head is mostly a metallic green, becoming more bronze-tinged on the rump and uppertail. The underparts are white with the unique buffy patches on the wings and base of the tail. The females lack the colorful wing patches and are generally duller in plumage overall. Both sexes have relatively short straight bills and deeply forked tails. Juveniles resemble adult females but with pale spotting on the throat.
Distribution and Habitat
The Buff-winged Starfrontlet has an extremely limited range confined to the Andes Mountains of Venezuela, Colombia, Ecuador and far northern Peru. The total global population is estimated at just 2500-9999 mature individuals. Its habitats are humid montane forests and elfin woodlands at elevations between 2500-3700 meters. It tends to forage along forest edges, in clearings and in shrubby second growth. Flowers of plants such as fuchsias, passionflowers and shrubs in the heather family provide nectar. The hummingbird’s small size allows it to access nectar in flowers with very short corollas.
Feeding
Like all hummingbirds, the Buff-winged Starfrontlet feeds mainly on nectar from flowers using its specialized long tongue. It takes nectar by licking with its forked tongue at a rate of up to 15-17 licks per second. The bill is used to pierce at the base of flowers to access nectar the tongue cannot reach. In addition to nectar, these hummingbirds will eat small insects and spiders to obtain protein and minerals. Aerial insects are captured during flight or may be picked directly off leaves and branches. The Buff-winged Starfrontlet frequents a preferred network of nectar plants, visiting each flower repeatedly multiple times per day. If food resources become scarce, the hummingbird can enter a hibernation-like state called torpor to conserve energy.
Vocalizations
Male Buff-winged Starfrontlets produce high-pitched squeaky vocalizations during courtship displays. They can make multiple different calls, including metallic chips given in aggressive interactions with other males. Their rapid wingbeats, used for hovering and forward flight, create a loud buzzing hum. Males perform dive displays up to 12 meters in the air then plunge downward to impress females. The tail feathers are splayed and the wings held stiffly during these display dives.
Reproduction
The breeding season for Buff-winged Starfrontlets coincides with peak flower availability from April to July in Colombia. Courtship displays by the males occur at leks, where the birds gather at traditional sites. After mating, the female alone builds a small cup nest on a high horizontal branch, wrapping it in moss, lichen and other materials. She incubates the two tiny white eggs for about 15-19 days until they hatch. The female cares for the young chicks for another 20-26 days until they fledge. The chicks rely on the female for brooding, feeding and protection. Surviving fledglings reach sexual maturity at 10-12 months old.
Threats and Conservation
Although still relatively common, the Buff-winged Starfrontlet’s small native range and fragmented habitat make it vulnerable to extinction. Climate change poses a threat as warming temperatures cause the cloud forests it depends on to recede further up mountain slopes. Logging, fires, cattle grazing and mining also degrade and destroy key habitat. Parts of the range are protected in parks and reserves but more habitat conservation is needed. Eco-tourism focused on birdwatching provides an incentive to preserve cloud forests and the unique species they harbor. However, care must be taken to minimize disturbance to fragile bird communities. More research is needed on the basic biology and population trends of this little-known Andean hummingbird. With appropriate habitat management and conservation measures, the amazing Buff-winged Starfrontlet can continue gracing the treetops of cloud forests well into the future.
In summary, the Buff-winged Starfrontlet is a diminutive yet distinctive hummingbird constrained to very specific cloud forest habitat in the northern Andes. Some remarkable adaptations allow it to inhabit the cold high-altitude environment. The major threats it faces are climate change and habitat loss. Greater habitat protections and interest in bird-focused eco-tourism may aid conservation efforts for this species. There are still gaps in our knowledge of the Buff-winged Starfrontlet’s ecology and behavior that warrant further scientific study. With increased understanding and management focus, this unique hummingbird can remain an integral part of Andean cloud forest communities.