Allen's Hummingbird

Allen's hummingbird was formally described by the French naturalist René Lesson in 1829 and given the binomial name Ornismya sasin. The Allen's hummingbird is part of the family Trochilidae, which covers over 300 species of hummingbirds found primarily in the Americas. The specific epithet is a Wakashan or Nootka Native American name for a hummingbird. The type locality is San Francisco. Allen's hummingbird is now placed in the genus Selasphorus, which was introduced by William Swainson in 1832. The common name commemorates Charles Andrew Allen, an American collector and taxidermist who identified the bird in 1879 in Nicasio, California. Two subspecies are recognised:

Allen's hummingbirds are commonly found in locations such as the brushy woods, gardens, and meadows of coastal California from Santa Barbara north, and southern coastal Oregon. Individuals breeding along these coasts migrate to central Mexico for the winter, while birds breeding on the Channel Islands and in southern California are mainly year-round residents. The migratory habits of Allen's hummingbirds are closely linked to the availability of food sources, which affects their breeding success and survival rates. Male and female migratory patterns do not occur at the same time – the males head back north first early in the year, while the females arrive closer to spring, preparing to breed. This difference in timing helps reduce competition for food and nesting sites between males and females during the breeding season. This population colonized the Palos Verdes Peninsula of Los Angeles County in the 1960s and has since spread over much of Los Angeles and Orange Counties, south through San Diego County, and east to the western end of Riverside County. The elevations in which these birds breed vary, peaking at around 1,000 feet. Allen's hummingbirds are increasingly threatened by human actions and habitat loss, an impact causing their population to decline by about 80% since the 1960s.

The courtship flight of male Allen's hummingbirds is a frantic back-and-forth flight arc of about similar to the motion of a swinging pendulum, followed by a high-speed dive from about during which tail feathers emit a characteristic sharp flutter to further attract attention of the female. Male Allen's hummingbirds are aggressive and territorial, chasing other males and different hummingbird species from their territory. They have even been known to attack and drive off predatory birds much larger than themselves, such as kestrels and hawks. After mating, the male does not stay and help the female raise the young. Both male and females utilize high-pitched vocalizations in familial and territorial social settings. Its feeding on nectar from flowers supports pollination, including the endangered Western lily, other coastal lilies, and monkey flower. Also, similar to other birds, Allen's hummingbirds use their feet as a means of maintaining body temperature; in colder months, they often tuck their feet into their feathers during flight, which keeps them warmer, while in warmer months, they fly with their feet dangling to enable cooling.