![]() ![]() ![]() Northern range expansion Īnna's hummingbirds have the northernmost year-round range of any hummingbird. In response to rising temperatures at low elevations during climate change in the 21st century, Anna's hummingbirds have expanded their range into the cooler summer environments of higher-altitude (up to 2,825 metres (9,268 ft)) mountainous terrains of California, such as the Sierra Nevada. However, birds have been spotted far outside their range in such places as southern Alaska, Saskatchewan, New York, Florida, Louisiana, and Newfoundland. They tend to be permanent residents within their range. Distribution and habitat Īnna's hummingbirds are found along the western coast of North America, from southern Canada to northern Baja California, and inland to southern and central Arizona, extreme southern Nevada and southeastern Utah, and western Texas. As of 2021, the International Union for Conservation of Nature Red List of Threatened Species lists the Anna's hummingbird among species of least concern. Population and trend Īccording to a 2021 estimate, there are 8 million Anna's hummingbirds in the western United States and Canada, with the population increasing since 1970. Anna's hummingbirds have adapted to urban environments and are commonly seen in backyards and parks, and at feeders and flowering plants. The male's call – scratchy and metallic – is typically used as the bird perches in trees and shrubs. Male birds with elevated levels of protein in their diet have more colorful crowns and higher iridescence in their head feathers compared with male birds with low protein intake. The barbules reflect incident light in the manner of partially-opened Venetian blinds, enabling the iridescence – which varies the head and gorget coloration with the changing angle of light – as a coloration advantage for courtship attraction and territory defense. The iridescence results from large stacks of melanosomes in the feather barbules, occurring as layers separated by keratin. The male has a striking reddish-pink crown and gorget, which are strongly iridescent and dependent on the angle of illumination and observation by female or male competitor birds. Females and juvenile males have a dull green crown, a grey throat with or without some red iridescence, a grey chest and belly, and a dark, rounded tail with white tips on the outer feathers. The male Anna's hummingbird is the only North American hummingbird species with a red crown. A male bird displaying its iridescent head feathers Females also have iridescent red gorgets, although they are usually smaller and less brilliant than the male. 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. Their bills are long, straight, and slender. They have an iridescent bronze-green back, a pale grey chest and belly, and green flanks. Description Īnna's hummingbirds are 3.9 to 4.3 in (9.9 to 10.9 cm) long with a wingspan of 4.7 inches (12 cm) and a weight range of 0.1 to 0.2 oz (2.8 to 5.7 g). The species is monotypic: no subspecies are recognised. ![]() The specific epithet anna was chosen to honour Anne d'Essling who married the ornithologist François Victor Massena, 3rd Duke of Rivoli. 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"). Anna's hummingbird is now placed in the genus Calypte that was introduced in 1856 by the English ornithologist John Gould. Lesson placed it in the genus Ornismya and coined the binomial name Ornismya anna. They also consume small insects and other arthropods caught in flight or gleaned from vegetation.Īnna'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. These birds feed on nectar from flowers using a long extendable tongue. 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. 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. In the early 20th century, Anna's hummingbirds bred only in northern Baja California and Southern California. It is native to western coastal regions of North America. It was named after Anna Masséna, Duchess of Rivoli. Anna's hummingbird ( Calypte anna) is a medium-sized bird species of the family Trochilidae. ![]()
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |