Andean Emerald

The Andean emerald is 9 to 11 cm (3.5 to 4.3 in) long. Males weigh about 5.6 g (0.20 oz) and females about 5.3 g (0.19 oz). Both sexes of all subspecies have a straight to slightly decurved bill of medium length with a blackish maxilla and a coral red mandible with a dark tip. Adult males of the nominate subspecies U. f. franciae have a glittering violet-blue crown and glittering golden- to emerald green cheeks and neck. Their upperparts and flanks are light green to golden-green with a coppery tinge to the uppertail coverts. The center of their underparts is white. Their tail is bronze-green to copperish. The adult female is similar to the male but its crown is turquoise-blue to greenish and less glittering. Juveniles are similar to the adult female and also have brownish edges on the upperparts' feathers and grayish brown flanks. Subspecies U. f. viridiceps differs from the nominate with a shorter tail and a green crown. U. f. cyanocollis also differs slightly from the nominate; the blue of its crown extends to the nape.

The subspecies of Andean emerald are found thus:

U. f. franciae, Andes of northwestern and central Colombia U. f. viridiceps, Andes from southwestern Colombia's Nariño Department through western Ecuador to Loja Province U. f. cyanocollis, Andes of southeastern Ecuador's Zamora-Chinchipe Province and northern Peru's Marañón River valley south and east to La Libertad Province The Andean emerald inhabits secondary forest and the edges and clearings of wet primary forest. In Peru it also occurs in drier shrublands. In elevation it ranges between 600 and 2,100 m (2,000 and 6,900 ft) and is most common above 1,000 m (3,300 ft).

The Andean emerald forages for nectar at a variety of flowering herbs, vines, and trees, usually from the middle to upper strata of the forest. It forages by trap-lining, visiting a circuit of nectar sources. It sometimes mixes with other hummingbirds at flower patches but is subordinate to territorial species. In addition to nectar it feeds on insects by hawking from a perch.