Oasis
Common name: Oasis Hummingbird
Scientific name: Rhodopis vesper
Clades: Mellisugini - Bees
The Oasis Hummingbird is a small hummingbird that thrives in the desert lowlands and foothills. This species is often found in gardens, agricultural areas with flowers, and native scrub, where it is frequently quite common.
The Oasis Hummingbird can be identified by its rather long, arched bill and a distinctive pale rusty rump patch. It is appreciably larger than most other superficially similar hummingbirds in its range, such as the Peruvian Sheartail.
The adult male upperparts are an olive-green, with a cinnamon or cinnamon-rufous rump and uppertail coverts. It features a small white spot behind the eye. The tail is deeply forked, with the two outer pairs of feathers narrower and slightly curved inward. The central tail feathers are grayish olive, while the remaining feathers are purplish brown. Its iridescent gorget ranges from rosy violet to purple, becoming turquoise on the sides. The underparts are whitish to dull white, with flanks washed in dull green. Most sources indicate that this plumage is retained year-round, although there is mention of an "eclipse plumage," where the male’s throat appears scaled drab brown.
The female’s upperparts resemble the male’s, but her tail is much shorter and only slightly forked. It is slightly double-rounded, with the third and fourth pairs of feathers slightly longer than the central pairs and the outermost pair. The upper surface of her tail feathers is olive green or bronzy green, all but the central pair tipped with white and featuring a broad black subterminal bar. Her underparts are pale gray, pale buff, or pale grayish buff, darker on the flanks.
The immature males are similar to adult females but have a speckled throat with a few iridescent feathers.
3 subspecies:
R. v. koepckeae
Distribution NW Peru (Cerro Illescas, in SW Piura).R. v. vesper
Distribution most of W Peru (S from Lambayeque) and extreme N Chile (Tarapacá).R. v. atacamensis
Distribution N Chile (Atacama); probably this subspecies also farther south (Coquimbo).