Aglaeactis castelnaudii
The White-tufted Sunbeam, *Aglaeactis castelnaudii*, is a striking, medium-sized hummingbird renowned for its iridescent plumage and adaptation to extreme high-altitude environments of the Peruvian Andes. Measuring approximately 12-13 cm in length, including its tail, and weighing 7-9 grams, it exhibits brilliant bronzy-green upperparts that shimmer with fiery coppery-red to violet hues on the rump, particularly in good light. A key field mark is the distinctive white patch on its flanks, oft...
This specialized hummingbird inhabits humid montane scrub, open *Polylepis* woodlands, and paramo edges, frequently found near rocky slopes. It thrives at impressive elevations, typically ranging from 3,000 to 4,800 meters, sometimes even venturing up to 5,000 meters above sea level.
Its primary diet consists of nectar, extracted from a variety of high-altitude flowering plants such as *Bomarea*, *Brachyotum*, *Centropogon*, *Chuquiraga*, *Salvia*, and *Puya*. It supplements its diet by gleaning small arthropods like insects and spiders for essential protein.
The White-tufted Sunbeam is a diurnal species, active throughout the daylight hours, though it may enter torpor during cold nights to conserve energy. Its foraging strategy primarily involves hovering at high-altitude flowers, employing a trap-lining approach where it visits a circuit of flowerin...
The White-tufted Sunbeam is endemic to the high Andes of central and southern Peru, inhabiting a relatively restricted but robust range. Its distribution spans various departments, including Ancash, Huánuco, Junín, Lima, Pasco, Apurímac, Cusco, and Ayacucho. While primarily resident throughout it...
Least Concern
- The White-tufted Sunbeam is one of the highest-altitude hummingbirds in the world, regularly found above 4,000 meters. - Its genus name, *Aglaeactis*, translates to 'splendid ray,' a fitting description for its brilliantly iridescent plumage. - To survive the frigid Andean nights, this species ...