Santa Marta Woodstar

The Santa Marta woodstar (Chaetocercus astreans) is a species of hummingbird in tribe Mellisugini of subfamily Trochilinae, the "bee hummingbirds". It is endemic to Colombia.

Taxonomy and systematics: The Santa Marta woodstar and several other species in genus Chaetocercus were formerly placed in genus Acestrura. In addition, it was for a time treated as a subspecies of the gorgeted woodstar (C. heliodor). It has been in its current position since the late 20th century. It is monotypic.

 The Santa Marta woodstar is about 7 cm long. Both sexes have a straight black bill. The male´s head is shiny green and the rest of the upperparts dark shiny bluish. It has a reddish gorget that extends across the neck. The breast is gray and the belly bluish with a white spot on the flanks. The tail is forked, with very short central feathers and outer ones that are bare shafts. The female is bronzy green above and pale cinnamon-rufous below with a dark cheek patch and, like the male, a white spot on the flanks. Its rounded tail has green central feathers and the rest are cinnamon with a black bar near the end.

Distribution and habitat: The Santa Marta woodstar is found only in the isolated Sierra Nevada de Santa Marta of northern Colombia. It inhabits the edges of montane forest, semi-open woodlands, and coffee plantations, and occasionally visits the lower parts of the páramo. In elevation it ranges between 825 and.

Movement: The Santa Marta woodstar´s movements, if any, are not known but seasonal elevational changes are thought likely.

Feeding: The Santa Marta woodstar feeds on nectar and insects, though no details are known. It is assumed to have a foraging strategy and diet like those of its close relative the gorgeted woodstar. That species feeds from vegetation´s middle strata to the canopy; one important source is the flowers of Inga trees. It does not defend feeding territories, and because of its small size and slow bumblebee-like flight is sometimes able to feed in the territories of other hummingbirds.

Breeding: Nothing is known about the Santa Marta woodstar´s breeding phenology.

Vocalization: The Santa Marta woodstar´s vocalizations have seldom been recorded. What is possibly its song is "a regularly repeated, single, modulated squeaky note." It makes "a series of single liquid ´tsit´ notes or a doubled ´ti-tsit´" calls while hovering or feeding.

Status: The IUCN has assessed the Santa Marta woodstar as being of Least Concern. Though it has a limited range and its population size is unknown, the latter is believed to be stable. It is considered locally common and readily accepts some human-altered landscapes like coffee plantations, though some of its natural habitat is under threat of deforestation.