If you live along the Pacific Coast and see a hummingbird in January, this is your bird. The Anna’s Hummingbird is the West Coast’s year-round resident, hardy enough to hold its ground through winters that send every other North American hummingbird south. It is also the only hummingbird in North America whose entire head, crown and throat both, blazes rose-pink, and the only one whose males sing a real, learned song.

And it is a bird with a remarkable recent history. A century ago you would not have found one north of Southern California. Today it nests in British Columbia, and the reason is largely us.

Quick Facts

• Scientific name: Calypte anna
• Length: about 3.9 to 4.3 inches
• Weight: roughly that of a nickel
• Range: Pacific Coast from Baja California to British Columbia, east into Arizona; largely non-migratory
• Named for: Anna Masséna, Duchess of Rivoli, by French naturalist René Primevère Lesson in 1829
• Conservation status: common, and expanding

How to Identify an Anna’s Hummingbird

The male is unmistakable when the light is right. Both his crown and his throat are iridescent rose-pink to magenta, making him the only North American hummingbird with a fully red-pink head. His back is metallic emerald green, his underparts grayish. He is stocky and relatively large-headed for a hummingbird, with a short, straight bill.

As with all iridescent gorgets, that magenta vanishes at the wrong angle and the whole head reads as dark or black. If a hummingbird on the West Coast looks like it is wearing a black hood, wait for it to turn. The science of that effect is in the article on why hummingbirds are so colourful.

The female is subtler but has a giveaway most female hummingbirds lack: a small patch of red spotting in the center of her throat, sometimes forming a tiny gorget of its own. That alone separates her from most other female hummingbirds, which have plain throats. Otherwise she is dull iridescent green above, dingy gray below, usually with a whitish mark over the eye.

Overall impression: gray and green, with no buff or orange tones anywhere. That absence is a useful field mark in itself, since the western Selasphorus hummingbirds are washed with rufous.

Similar Species

• Costa’s Hummingbird is the closest relative and the main confusion. The male Costa’s gorget is violet-purple rather than rose-pink and flares much further down the sides of the neck into a pointed “mustache.” If an Anna’s-shaped bird looks more violet than rose, consider a Costa’s, or even an Anna’s–Costa’s hybrid, which do occur.
• Black-chinned Hummingbird has a noticeably longer bill and a black throat with only a thin violet band.
• Rufous and Allen’s are smaller and carry obvious orange tones that Anna’s never shows.

For the wider picture, see the article on North American hummingbird species.

Range, and a Range Expansion Worth Knowing About

In the first half of the twentieth century, Anna’s Hummingbird bred only in northern Baja California and Southern California. That was the whole of it.

Then the range began moving north and east, and it has not stopped. The species now breeds up the coast through Oregon and Washington into British Columbia, occurs regularly in southeast Alaska, and has pushed east into Arizona. Research points to two human causes: the widespread planting of exotic flowering trees and ornamental garden plants, which supplied nectar and nesting sites where none existed before, and the growth of backyard feeding. A 2017 study specifically linked the winter range expansion to urbanization and supplementary feeding.

It is a rare and cheering thing: a bird whose range grew because of what people did, rather than shrinking because of it. If you keep a feeder anywhere on the Pacific Coast, you are part of that story.

Anna’s favors open and scrubby habitat, chaparral, desert scrub, oak woodland, and takes readily to suburban yards, parks, and gardens. Most individuals stay put year-round, though some southwestern birds make a modest east-west movement, with Arizona birds shifting toward the California coast after nesting.

The Winter Hummingbird

Along the coast, Anna’s is often the only hummingbird present in winter, and it is markedly more cold-hardy than its relatives. It survives freezing nights the same way all hummingbirds do, by entering torpor, a deep dormancy that slows the body almost to a standstill until morning. Its willingness to take insects, spiders, and tree sap as well as nectar may help it through the lean months, since that protein-rich diet supports the metabolism cold weather demands.

For the full science of how a three-gram bird survives a freezing night, see how hummingbirds survive winter: the science of torpor.

If you host Anna’s through the winter, keep your feeder up all year. The practical challenge is simply keeping the nectar from freezing, which our nectar recipe and feeder article cover, along with when to put feeders out and take them down everywhere else.

The Dive, and the Sound It Makes

The male’s courtship display is one of the great performances in North American birding. He hovers in front of the female, then climbs as high as 130 feet, and dives. At the bottom of the plunge he pulls up sharply and produces a loud, explosive pop or chirp. The whole sequence takes about twelve seconds.

For years that noise was assumed to be vocal. It is not. Research by Christopher Clark and Teresa Feo established that the sound is made by the bird’s tail feathers vibrating as air rushes past them at the bottom of the dive, a mechanism called sonation. The Anna’s Hummingbird, in the title of their paper, chirps with its tail.

The dive is also astonishingly fast, fast enough that measurements of it produced a vertebrate speed record, which we cover in our article on hummingbird predators and defences. And males will aim the display at intruders as well as at females, including at people, so if an Anna’s has ever dive-bombed you in the garden, you were being told off.

The song matters too. Anna’s males sing more than any other North American hummingbird: a thin, scratchy, buzzy song delivered from a perch, often for long stretches. What makes it genuinely unusual is that these songs are complex and learned, which is rare outside the songbirds. Read more on hummingbird vocalizations in the article on hummingbird sounds and territorial behaviour.

Breeding

Anna’s Hummingbirds nest remarkably early, sometimes beginning in December and typically well before spring, which is possible precisely because they do not migrate away.

The female does all the work, as in every hummingbird species. She builds a compact cup of plant fibers bound with spider silk, lined with plant down and sometimes feathers, and camouflaged outside with lichen. Nest sites are variable, usually 4 to 25 feet up on a branch, in vines, on a wire, or under an eave. The article on hummingbird breeding and nests covers the full cycle.

Attracting Anna’s Hummingbirds

They are among the easiest hummingbirds to attract, being both common and thoroughly comfortable around people.

Keep a clean feeder up year-round if you are within their range. Plant tubular-nectar flowers, including natives suited to your area; in the Pacific Northwest specifically, red-flowering currant (Ribes sanguineum) is an outstanding early-season shrub. Skip broad-spectrum pesticides so the insects and spiders they need remain available. The article on attracting hummingbirds explains this in more detail.

Frequently Asked Questions

How do I identify an Anna’s Hummingbird? Look for a stocky green-and-gray hummingbird with no orange tones. Males have a rose-pink crown and throat, the only North American hummingbird with a fully red-pink head. Females show a small red patch in the center of an otherwise plain throat.

Do Anna’s Hummingbirds migrate? Mostly not. They are year-round residents along the Pacific Coast, though some southwestern birds make short east-west movements after nesting.

Why do Anna’s Hummingbirds stay through winter? They are unusually cold-hardy, surviving freezing nights through torpor, and the ornamental plantings and feeders of suburban gardens supply food when little else is blooming.

What is the popping sound a male makes when he dives? It is made by his tail feathers vibrating in the rushing air at the bottom of the dive, not by his voice. Researchers call this sonation.

Why has the Anna’s Hummingbird’s range expanded so much? Exotic flowering plants in gardens and the growth of backyard feeding gave the species food and nesting sites far north of its original range. It has spread from Southern California to British Columbia in about a century.

Should I feed Anna’s Hummingbirds in winter? Yes, if they are resident in your area. Keep the feeder up all year and prevent the nectar from freezing.

Conclusion

The Anna’s Hummingbird is the West Coast’s constant: the one that does not leave, that sings from a bare branch in February, that flings itself 130 feet into the air and chirps with its tail on the way down. It is also a small, bright piece of evidence that what we plant and what we hang in our gardens genuinely changes where wild things can live. A hundred years ago this bird had no business being as far north as Vancouver. Now it spends the winter there.