Anna's hummingbird

Anna's hummingbird (Calypte anna) is a North American species of hummingbird. It was named after Anna Masséna, Duchess of Rivoli. It is native to western coastal regions of North America. In the early 20th century, Anna's hummingbirds bred only in northern Baja California and Southern California. The transplanting of exotic ornamental plants in residential areas throughout the Pacific coast and inland deserts provided expanded nectar and nesting sites, allowing the species to expand its breeding range. Year-round residence of Anna's hummingbirds in the Pacific Northwest is an example of ecological release dependent on acclimation to colder winter temperatures, introduced plants, and human provision of nectar feeders during winter. These birds feed on nectar from flowers using a long extendable tongue. They also consume small insects and other arthropods caught in flight or gleaned from vegetation. Anna's hummingbird was formally described and illustrated in 1829 by the French naturalist René Lesson in his Histoire naturelle des Oiseaux-Mouches from a specimen that had been collected in California. Lesson placed it in the genus Ornismya and coined the binomial name Ornismya anna. Anna's hummingbird is now placed in the genus Calypte that was introduced in 1856 by the English ornithologist John Gould. Gould did not explain the derivation of the genus name but it is probably from the Ancient Greek kaluptrē meaning "woman’s veil" or "head-dress" (from kaluptō meaning "to cover"). The specific epithet anna was chosen to honour Anne d'Essling who married the ornithologist François Victor Massena, 3rd Duke of Rivoli. The species is monotypic: no subspecies are recognised. Anna's hummingbirds are long with a wingspan of and a weight range of . They have an iridescent bronze-green back, a pale grey chest and belly, and green flanks. Their bills are long, straight, and slender. The adult male has an iridescent crimson-red, derived from magenta, to a reddish-pink crown and gorget, which can look dull brown or gray without direct sunlight, and a dark, slightly forked tail.