Anna’s Hummingbird is a medium-sized stocky hummingbird that is hailed as the most common hummingbird along the Pacific Coast. Along with the Allen’s and the Costa’s Hummingbirds, Anna’s is one of the only three species that exclusively live in the US or Canada, even during winter.
Anna’s Hummingbirds are highly distinguished for their unique physical appearance. They have iridescent emerald feathers and sparkling rose-pink throats, making them look like flying jewelries rather than birds. With this, their small size didn’t prevent them from making a strong impression.
In the early half of the 20th century, the Anna’s Hummingbird exclusively bred in northern Baja California and southern California. The expansion of the bird’s breeding range was mainly attributed to the planting of rare flowering trees, which provided nectars and nesting sites to the hummingbirds.
The bird’s name was attributed to Anna Masséna, the Duchess of Rivoli – wide of a 19th century bird collector, Duke Victor Massena.
The length of the body of Anna’s Hummingbird is 3.9 to 4.3 inches. And the most dominant color combination in the bodies of Anna’s Hummingbirds are green and gray.
The bird has an iridescent bronze-green back, a pale grey chest and belly, and green flanks. Its bill is described as long, straight and slender.
There are iridescent reddish-pink feathers that cover the adult male’s head and throat that may look dull in the absence of direct sunlight. The gorget of Anna’s Hummingbird extends over its head, which makes it more of a balaclava rather than a bib. Interestingly, female Anna’s display a tiny red gorget, while most hummingbird species do not have any.
For the record, Anna’s Hummingbird is the only North American hummingbird species that exhibit a red crown.
Anna’s Hummingbirds are usually found in urban and suburban settings, such as yards, parks, residential streets, and others. They are also commonly seen in wilder places such as chaparral, riverside woods, savannahs, and coastal scrubs. Most notably, they often lurk around eucalyptus trees, even though eucalyptus was only introduced to the West Coast in the mid-nineteenth century.
Anna’s Hummingbirds are often seen looking for food during the day. Also, they readily approach hummingbird feeders and flowering plants.
They use their long, extendable tongue in feeding on nectar from different types of flowering plants, which include currant, gooseberry, and manzanita. They also eat nectars from introduced species such as eucalyptus.
Aside from nectar, they also eat various types of insects from understory leaves, crevices, stream banks, or caught in the webs of spider, plucked from the air, or taken from flowers. They prefer eating small insects like midges and whiteflies. Sometimes, they also eat tree sap that leaks out from the holes made by sapsuckers. Because of this diet, bees and wasps may become impaled on the Anna’s Hummingbird’s bill, which leads to their starvation and eventual death.
Nesting and Behavior
An adult male Anna’s Hummingbirds displays an interesting courtship behavior. He would hover in front of the hummingbird or person by 2 to 4 meters, and then climb high into the air, up to about 131 feet. Then, he would swoop to the ground in a near-vertical dive, which ends with a high-pitched noise near the display object. After which, he will make a circular arc back to his origin. On sunny days, the dives are coordinated in such a way that the sun is reflected from the iridescent throat and crown directly at the object. The dive display would last up to 12 seconds.
As the courtship slowly progresses, the male would chase the female Anna’s, who will lead him towards the location of her nest, where he will perch again. There, the male Anna’s will perform a “shuttle display”, seining back and forth above the female while his body horizontal and his head down toward the female. He does this while singing a song.
The nest is built out of plant down and spider webs. The female Anna’s would normally just sit in the nest while building the cup rim around her. After a week, the nest, which is about 1 inch tall by 1.5 inches in diameter, is already completed. The nest can be a combination or parts of cattail, willow, leaves, thistle, or small feathers that are bounded together by spider webs or cocoons of insects. Other paraphernalia, such as lichens, mosses or paint chips, may be stolen items from other active nests.
The male Anna’s Hummingbirds are often found perching above head level in trees and shrubs and making a scratchy metallic sound. Male and female Anna’s hummingbirds do not form pairs. Moreover, both sexes would possibly mate with more than one individual every season. The males do not participate in taking care for the baby hummingbirds.
The normal body temperature of Anna’s Hummingbirds is around 107 degrees Fahrenheit, which is too high for humans. When the environment gets extremely cold, Anna’s Hummingbirds, along with other hummingbird species, enter into torpor, which is a state of decreased physiological activity in an animal. As a result, their breathing and heart rate slow down, and their body temperature can fall as low as 48 degrees Fahrenheit. The hummingbirds become active as soon as the outside temperature rises again.
Another fun fact about Anna’s Hummingbirds is that they can shake their bodies 55 times per second while flying. This behavior is associated to shaking off any pollen or dirt from their feathers. With such a fast rate, the shaking of Anna’s Hummingbirds is said to be the fastest of any vertebrate on earth.
With an estimated population of 1.5 million, Anna’s Hummingbirds are not considered an endangered species and their population appears to be stable.
According to the North American Breeding Bird Survey, there was a recorded 2 percent increase in the population of Anna’s Hummingbirds. Another estimate suggest that the global breeding population of the species runs at 5 million, with 96 percent in the United States.
Anna’s Hummingbird rates an 8 out of 20 on the Continental Concern Score. The bird is also not included in the 2012 Watch List. Because of its strong thriving abilities, Anna’s Hummingbird has become the most common hummingbird on the West Coast, even extending its numbers of occurrences to as far as Vancouver, Canada.