The black-hooded sunbeam (Aglaeactis pamela) is a species of hummingbird found in the Andes mountains of South America. With its distinctive black hood and bright orange-yellow chest, it is one of the most striking members of the hummingbird family.
Description
The adult male black-hooded sunbeam has brilliant iridescent orange-yellow underparts from chin to vent. The rest of the body is an iridescent bronzy-green. The namesake black hood runs from the base of the bill back over the head and nape. The bill is long, slim and curved. Females are similar but lack the black hood and have greener underparts. Juveniles resemble adult females but have buffy edges to the feathers.
This medium-sized hummingbird reaches lengths of 11-12 cm and weighs 5-7 grams. The wingspan is approximately 6.5 cm. Males are slightly larger than females.
Distribution and Habitat
The black-hooded sunbeam is found along the Andes mountains of Peru, Bolivia and far northern Chile and Argentina. Its preferred breeding habitat is humid montane forest and elfin forest at elevations of 2000-4600 meters. It frequents forest edges and clearings where flowers grow.
In the southern part of its range, it migrates to lower elevations in winter. Further north where winters are less severe, populations may remain in the breeding areas year-round.
Diet
Like all hummingbirds, the black-hooded sunbeam has a fast metabolisms and feeds on flower nectar and small insects. Its long curved bill allows it to access nectar from long tubular Andean flowers. Favored nectar sources include species in the genera Bomarea, Angelica, Nicotiana, Ipomopsis and others. The bird also hawks small insects in flight.
Reproduction
The breeding season ranges from August to December. Males are promiscuous and mate with multiple females. The female alone builds the tiny cup nest out of soft plant fibers such as moss and attaches it to a vertical branch. She incubates the two white eggs for 15-19 days until they hatch.
The chicks are born blind, naked and completely helpless. They develop quickly though, putting on weight and feathers rapidly. After about a month they are ready to fledge from the nest. The female continues to feed them for another 2-3 weeks as they learn to forage on their own.
Threats and Conservation
While still relatively common over much of its range, the black-hooded sunbeam does face some threats. Habitat loss from deforestation and conversion to agriculture is the main issue. Climate change may also pose problems by altering flower availability.
The species is not considered globally threatened however, and is classified as Least Concern by the IUCN. Population trends will need to be monitored, especially in the southern part of its range. Conservation efforts should focus on habitat protection, limiting deforestation in Andean cloud forests.
Interesting Facts
– The male’s spectacular iridescent hood is thought to be used to attract females and repel rival males. Males display the hood during aggressive displays and courtship.
– The Andes harbor over 100 of the world’s approximately 330 hummingbird species. The black-hooded sunbeam is one of 12 species in the brilliant-thighed clade endemic to the region. This radiation of Andean hummingbirds evolved to take advantage of the wealth of flower diversity.
– Like many other hummingbirds, the black-hooded sunbeam can go into torpor – a temporary hibernation – at night to conserve energy. Body temperature drops markedly and the bird becomes lethargic.
– The genus name Aglaeactis refers to the colorful, shining birds in this group. Pamela honors Lady Pamela Greville who financed the expedition on which the species was first collected.
In summary, the black-hooded sunbeam is a beautiful and fascinating Andean hummingbird adapted to the forests and flowering plants of high elevations. While not globally threatened, care should be taken to protect its specialized habitat which is vulnerable to human activities. This sunbeam provides just one example of the amazing diversity of hummingbirds found in South America.