Anna's Hummingbird | |
---|---|
male | |
female | |
Scientific classification | |
Kingdom: | Animalia |
Phylum: | Chordata |
Class: | Aves |
Order: | Apodiformes |
Family: | Trochilidae |
Genus: | Calypte |
Species: | Calypte anna |
A common sight in North America, this flashy hummingbird is a regularly spotted bird near backyard feeders.
Appearance[]
Anna's hummingbirds are small hummingbirds; about 4 inches in length, with a relatively short, straight bill and a long sloping forehead. They have an iridescent green back and grayish-white underparts and greenish or golden flanks. This hummingbird has dark wing feathers and pale tufts on their rump.
The male has a colorful rose-colored crown that extends from the top of their head to their neck. Females have only a small patch. Males also have partial pale eyerings, while females have a white spot behind their eye. Females also have black tails with white tips, while the males' tails are solid blackish-gray. Immature hummingbirds resemble females.
Occurrence[]
Anna's Hummingbirds can be found around the coast of British Columbia to northern Mexico. They've recently began expanding to Arizona and Canada.
Anna's Hummingbirds live in a wide variety of habitats. Chaparral is their traditional habitat, although in recent years they have been found more often in suburban gardens where hummingbird feeders and exotic plantings provide them with food throughout the year. This allows the Anna's Hummingbird to expand their range.
Life History[]
Diet[]
Anna’s Hummingbirds eat nectar from many flowering plants and feeders. They also eat a wide array of insects from understory leaves, crevices, streambanks, or caught in spider webs, plucked from the air, or taken from flowers. These birds primarily target smaller insects. Anna's Hummingbirds also feed on tree sap (and insects caught in it) leaking out from holes made by sapsuckers.
Hummingbirds feed about 5-10 times per hour for 30-60 seconds each time. They feed through a long, tube-like tongue that darts into the flower's corolla for nectar. The tongue, shaped like a "W", uses capillary action to absorb the nectar, much like a paper towel absorbs water.
Nesting[]
They begin nesting in December, or even earlier.
Nest site is variable, usually on a branch of tree or shrub, sometimes in vines, on wires, under eaves.
Females choose the nest site, usually a horizontal branch of trees or shrubs 6-20 feet off the ground (occasionally higher) near a source of nectar. They often build nests in oak, sycamore, or eucalyptus trees, but they may use vines, shrubs or even poison oak. They use conifers less frequently.
The female builds the nest out of plant down and spider webs, sitting in the nest and building the cup rim up around her. Nests take around a week to build and are 1 inch tall by 1.5 inches in diameter. They may be built of cattail, willow, leaves, thistle, or small feathers and bound together by spider webs or insect cocoons. They may decorate the outside with lichens, mosses, or even paint chips. They sometimes steal these from other active nests.
The female only incubates the eggs and incubation period lasts from 14 to 19 days. Clutch size are from 2 to 3 eggs and Anna's Hummingbirds raise 2 to 3 broods per year.
Behavior[]
A hummingbird can rotate each of its wings 360 degrees, allowing them to be the only bird that can fly forwards, backwards, up, down, sideways, or hover. To hover, hummingbirds move their wings forward and backward in a repeated figure eight. Hummingbirds can move instantaneously in any direction, instantly accelerate their flight speed, and doesn't need to slow down to land. Hummingbirds can even fly short distances upside down, a trick rollover they employ when being attacked by another bird.
One of the most distinctive behaviors of the Anna's Hummingbird is the male's courtship flight dive. He flies as high as 130 feet in the air, then plummets toward the ground (and the watching female). At the bottom of the dive, he lets loose a unique, short high-pitched noise made by air whipping through his tail feathers. As courtship progresses, the male chases a receptive female, who leads him toward her nest site, and perches again. The male then performs a “shuttle display,” where he swings back and forth about a foot above the female, keeping his body horizontal and his head down toward the female, often singing an intense song. When males are not feeding or performing, they often sit fairly high in a bush or small tree, noisily chattering. Males and females do not form pairs, and both sexes likely mate with more than one individual per season. Both males and females defend feeding territories, although males defend more diligently and for a longer period of time. Only the females care for the young.
Vocalization[]
The song of an Anna's Hummingbird is composed of a series of buzzes, then a clearer, more tuneful whistle, followed by more emphatic chip notes; then the bird may repeat the whole set of buzz-whistle-chip sounds. The whole song lasts for 10 seconds or more, which is long for a hummingbird. Hummingbird calls are a series of short, sharp chip notes that may be given one at a time or one after another to make a twittering sound.
Displaying males make a loud squeak at the bottom of the courtship dive. For years, the dive noise was thought to be mostly vocal, but recent experiments and analysis of high-speed video show it comes from wind passing over the hummingbird's modified outer tail feathers.
Conservation[]
Since the 1950s, has expanded its breeding range both north and east. Very common in much of its range, adapting well to suburban areas.
Anna's Hummingbirds populations increased by over 2% per year between 1966 and 2014, according to the North American Breeding Bird Survey. Partners in Flight estimates the global breeding population at 5 million, with 96% in the United States, 13% spending part of the year in Canada and 15% in Mexico. They rate an 8 out of 20 on the Continental Concern Score, and are not on the 2014 State of the Birds Watch List. The Anna’s Hummingbird is the most common hummingbird on the West Coast, and it has thrived alongside human habitation. Its range has increased dramatically since the 1930s, when it was found only in California and Baja California. Thanks to widespread backyard feeders and introduced trees such as eucalyptus, it now occurs in healthy numbers all the way to Vancouver, Canada. Even so, Anna’s Hummingbirds can fall prey to outdoor cats in gardens where flowers grow close to the ground.