There's a bird that sings, that dive-bombs from 130 feet in the air with a sound produced entirely by its tail feathers, that has expanded its range faster than almost any bird in North American history — and that you've very likely already seen at your own feeder without knowing its full story. That's Anna's Hummingbird: the most familiar hummingbird on the Pacific Coast, and one of the most remarkable birds in North America once you look past the flash of pink at its throat.

Quick Facts

• Scientific name: Calypte anna
• Length: 3.9–4.3 inches (9.9–10.9 cm)
• Weight: 0.1–0.2 oz (2.8–5.7 g) — roughly the weight of a nickel
• Wingspan: about 4.7 inches (12 cm)
• Lifespan: typically 3–5 years in the wild; the oldest known wild individual lived at least 8 years, 2 months
• Population: an estimated 9.6 million, and growing — over 2% per year between 1966 and 2019 according to the North American Breeding Bird Survey
• Conservation status: Least Concern (IUCN); rated 7 out of 20 on Partners in Flight's Continental Concern Score, indicating low conservation concern
• Claim to fame: the only North American hummingbird species known to sing, and the hummingbird with the northernmost year-round range of any species in the world

The Origin Story: How Anna's Hummingbird Got Its Name

In 1829, French naturalist René Primevère Lesson described this species for science based on specimens collected by Paolo-Émilio Botta, originally naming it Ornismya anna. Lesson considered it one of the most beautiful hummingbirds he'd encountered, drawn to what he described as the "bright sparkle of a red cap of the richest amethyst" crowning the male's head — and he named the species in honor of Anna de Belle Masséna, the Duchess of Rivoli, whose husband owned the specimens.

In 1856, English ornithologist John Gould moved the species into a new genus he created specifically for it: Calypte, from the Greek word for "covered" or "hooded" — a direct reference to the male's iridescent crown, which extends up over the entire head rather than staying confined to the throat like most hummingbird gorgets. That full-head iridescence is still one of the easiest ways to recognize a male Anna's today, and it's part of what sets the genus apart; the only other living species in Calypte is Costa's Hummingbird, its close desert-dwelling cousin.

Within the broader hummingbird family tree, Anna's Hummingbird sits in what taxonomists call the "bee" radiation — a lineage that also includes the Ruby-throated and Rufous Hummingbirds familiar across the rest of the country. Hybridization between Anna's and Allen's Hummingbirds is well documented in the scientific literature, and if you ever spot a male with a throat that reads more violet than rose-pink, there's a real chance you're looking at a hybrid.

One of the Most Remarkable Range Expansions in North American Bird History

This is arguably the single most interesting fact about Anna's Hummingbird, and it's backed by real, peer-reviewed research: in the early 1900s, this species bred only along a narrow strip of the Pacific coast, from northern Baja California up to the San Francisco Bay area. That's it. Today, Anna's Hummingbirds breed as far north as Vancouver Island, British Columbia — over 700 miles beyond their historic range — and east through Arizona, with an increasing presence in New Mexico and West Texas.

What happened? A 2019 study led by researcher C.J. Battey used Christmas Bird Count records going back to the early twentieth century to document the pattern precisely: populations began growing in California in the early 1900s, and sites across the Pacific Northwest show a striking fit to simple exponential-growth models following colonization in the 1960s and 1970s. The driving forces were almost entirely human-created — the widespread planting of non-native ornamental flowering trees (eucalyptus chief among them) and the explosion of backyard hummingbird feeders gave the species year-round nectar in climates it previously couldn't have survived in without migrating.

Genetic research adds another layer to the story. A 2023 study published in Molecular Ecology (Adams et al.), carried out in partnership with the Bird Genoscape Project at UC Davis, sampled 241 individuals across the species' full range and found no evidence of local adaptation between the original and newly expanded populations — Anna's Hummingbird behaves as a single, genetically uniform group with high gene flow throughout. The researchers suggest the expansion may simply be too recent, starting in earnest in the 1940s, for evolutionary adaptation to have caught up yet. In other words: Anna's Hummingbird didn't evolve to survive in Seattle winters. It simply found enough artificial nectar and ornamental shelter to make survival possible anyway — and it's still figuring out the rest as it goes.

More recent research has also found the species expanding upward in elevation, into cooler high-altitude terrain in California's Sierra Nevada up to 9,268 feet, a pattern researchers link to climate change opening up new but still physiologically demanding habitat. USGS habitat mapping now tracks that shifting distribution across the species' full western range.

Key paper: Battey, C.J. (2019). "Ecological Release of the Anna's Hummingbird during a Northern Range Expansion." The American Naturalist.

How to Identify Anna's Hummingbird: Males vs. Females

Anna's Hummingbird is a stocky, medium-sized hummingbird with a straight, short-to-medium bill — heavier-looking than the slightly curved bill of its close relative, Costa's Hummingbird.

Adult Males

Unmistakable once you know what to look for: a full, iridescent rose-magenta crown and throat that extends over the entire head, not just the throat patch most other hummingbirds show. Depending on the light and viewing angle, this iridescence can look nearly black one moment and flash brilliant fuchsia-pink the next — it's structural color, produced by microscopic feather structures rather than pigment, which is why it seems to switch on and off as the bird moves. The back is iridescent bronze-green, and the underparts are a dull grayish-green.

Adult Females

Considerably less flashy: iridescent green upperparts, blackish wings, pale gray underparts, and — unusually for a female hummingbird — a small patch of iridescent reddish-pink spots on the throat, sometimes forming a partial gorget. Most female hummingbirds of other species have plain white throats, so this partial red throat patch is a useful Anna's-specific field mark. Look also for a small white spot behind the eye.

Immature Birds

Immature males look similar to females but are duller overall and lack a full gorget — they're still developing their adult throat coloring and may show only a few scattered iridescent flecks. Both immature males and females can be confused with females of other West Coast species, so the reddish throat spotting combined with the stocky build and straight bill are the most reliable combination of field marks.

A Quick Note on Sound

If you can't get a clear look, Anna's Hummingbird is often easier to identify by ear. Males are unusually vocal for a hummingbird, frequently singing a scratchy, buzzy song from an exposed perch — unusual behavior in this family, since most hummingbirds communicate primarily through visual displays and simple chip notes rather than sustained song.

Behavior: Bold, Vocal, and Fiercely Territorial

Anna's Hummingbirds are known for aggressively defending both feeding territories and nesting areas, chasing off rivals — and sometimes much larger birds — in fast, looping aerial pursuits accompanied by sharp chip calls. Females, while generally less conspicuous than males, will also defend feeding territories of their own, typically set up away from where males are displaying.

Bathing is a favorite activity: Anna's Hummingbirds are especially fond of bathing in dew-covered foliage in the early morning, fluffing and shaking their feathers thoroughly afterward.

Feeding and Diet

Anna's Hummingbird feeds from an unusually wide range of both native and non-native flowers. In its native chaparral habitat, it shows a particular fondness for currant and gooseberry (genus Ribes) and sage (Salvia) — both classic early-blooming natives that fuel the species through its unusually early nesting season. In developed, urban, and suburban areas, it readily turns to eucalyptus and tree tobacco (Nicotiana glauca), both non-native but abundant nectar sources.

Nectar is only part of the picture, though. Insects and spiders make up a critical part of the diet, providing protein that nectar simply can't. According to the American Bird Conservancy, a nesting female Anna's Hummingbird can capture as many as 2,000 insects a day — mostly tiny prey like midges and leafhoppers, either snatched mid-air or gleaned directly from spiderwebs and foliage. Anna's Hummingbirds have also been documented feeding on tree sap, sometimes visiting wells drilled by sapsuckers.

Courtship and Mating: The Most Dramatic Display in the Hummingbird World

Courtship in Anna's Hummingbird begins when a female enters a male's territory — typically after she's already started building a nest on her own, since males play no role in nest construction or chick-rearing. The resident male responds with one or more elaborate displays.

The shuttle display comes first in many encounters: the male flies rapidly back and forth in short, tight arcs directly above the perched female, body held horizontal, often flashing his gorget toward her with each pass.

The dive display is the main event, and it's spectacular. The male climbs as high as 130 feet into the air — Cornell Lab describes the full display lasting around 12 seconds — then plummets back down in a steep dive directly toward the watching female. At the bottom of the dive, he produces a loud, explosive popping or chirping sound. For decades, ornithologists debated whether this was a true vocal sound. High-speed video and wind-tunnel research eventually settled the question: the sound comes from air rushing over the male's specially modified outer tail feathers as he spreads them at the bottom of the dive, at speeds reaching 50–60 miles per hour — essentially turning his own tail into a musical instrument, not unlike a reed in a clarinet. Bioacoustics researcher Christopher Clark, who helped establish this mechanism, has noted watching female hummingbirds sit through the display with their eyes half-closed, "like listening to a symphony."

The same dive display doubles as a territorial warning to rival males or other intruders — including humans who get too close to an active territory.

Nesting and Family Life

Anna's Hummingbird has one of the earliest nesting seasons of any North American bird — nesting can begin as early as December in California, well before most other backyard birds have even started thinking about spring. This unusually early timing lines up directly with the bloom of early chaparral natives like currant and gooseberry.

The female alone selects the nest site, builds the nest, incubates the eggs, and raises the young — males contribute nothing beyond fertilization. Favored nest sites include a horizontal branch of oak, sycamore, or eucalyptus trees, typically 6 to 20 feet off the ground, though nests have been documented as low as 1.5 feet and as high as 30 feet. Vines, shrubs, and even human-built structures like wires and eaves are also used.

The nest itself is a real feat of construction: a compact cup about 1 inch tall and 1.5 inches in diameter, built from plant down and fibers bound together with spider silk, which gives the structure the stretch it needs to expand as the chicks grow. Construction usually takes about a week (ranging from 3 to 14 days), and the female continues adding material even after eggs are laid, decorating the exterior with lichen, moss — and in urban settings, sometimes even bits of paint chips or cigarette paper for camouflage.

Clutch size is typically two small white eggs, each about half an inch long. Incubation lasts 14–19 days, and the young are altricial — helpless, naked, and entirely dependent on the female — at hatching. A female Anna's Hummingbird may raise two, occasionally three, broods in a single season.

Migration: Mostly a Homebody, With Some Regional Exceptions

Unlike nearly every other North American hummingbird, Anna's Hummingbird is largely non-migratory. Most individuals along the Pacific Coast stay put year-round, which is precisely what makes this species so unusual and so valuable to backyard birders in Washington, Oregon, and coastal British Columbia — it's often the only hummingbird they'll ever see in January.

That said, the species isn't entirely stationary everywhere. Populations in the desert Southwest — particularly Arizona — show a real seasonal pattern: many birds move west toward California in mid-spring after the local nesting season wraps up, then return east again in late summer. Some individuals in this region are permanent residents instead, so the pattern isn't universal even within Arizona.

Seasonal elevational movement is also common: many populations shift to higher mountain elevations after breeding in summer, then drop back down to lower elevations for the winter — a very different pattern from the long-distance north-south migrations most other hummingbird species undertake.

Following Anna's Across the Regions

Most hummingbirds leave North America each fall. Anna's doesn't. It holds year-round territory along the Pacific Coast, and that resident status is recent in the north: Washington and Oregon had no year-round Anna's until the 1960s, and the population is still growing, helped along by feeders and non-native flowering plants. Inland, the range thins as it goes — year-round in Arizona and West Texas, holding on in southern Nevada and Utah where winters stay mild. Anna's Hummingbird's range now touches four of the eight U.S. birding regions, which is unusual for a species that barely migrates at all. Each region tells a different part of the story, and if you read them in this order, you're essentially watching a hundred-year range expansion unfold across a map.

• Pacific & West — Year-round resident. California is the core of the range; Anna's never leaves, and coastal birds nest as early as December.
• Pacific Northwest — The expansion zone. Western Washington and Oregon gained year-round Anna's only in the 1960s and 70s, and they're now the reason a hummingbird shows up at a snowy feeder in January. They're still expanding.
• Southwest — Present year-round, but not the same birds all year: many Arizona Anna's move west to California after spring nesting and return in late summer, while others stay put. Range extends into West Texas in the nonbreeding season.
• Mountain West — The frontier. Anna's is still scarce here, but records are climbing as the species pushes east and upslope. Anna's turns up across the interior mountain states as an occasional wanderer, with Idaho's records clustering around Boise and the northern panhandle.
• Rare Visitors — States with documented sightings but no established population. Alaska, Idaho, and Colorado are seeing occasional wanderers as the range pushes outward. New Mexico sits just past the current edge, with sightings increasing. Florida, Louisiana, and New York records are long-distance strays — single birds far off course.

Torpor: How Anna's Hummingbird Survives Cold Nights (and Cold Winters)

Hummingbirds burn energy at an extraordinary rate — researchers have compared a hummingbird's daily caloric intake, scaled to human size, to eating hundreds of hamburgers a day. At night, when they can't feed, most hummingbird species — Anna's included — cope by entering torpor: a controlled, dramatic drop in both body temperature and metabolic rate, essentially a nightly mini-hibernation. Body temperature can fall from a normal 105°F (40.5°C) down to as low as 48°F (9°C) or lower, depending on ambient conditions.

This is precisely what allows Anna's Hummingbird to survive truly cold winters in places like Seattle, enduring extended stretches of subfreezing temperatures, snow, and high wind that would be lethal to a bird trying to maintain a normal body temperature all night. Research has found that Anna's Hummingbirds living at colder, higher-elevation sites use torpor more frequently and for longer stretches than birds at lower, milder elevations — a direct physiological response to a harsher environment, not just a fixed trait.

Torpor comes with a real trade-off, though, which becomes especially important during nesting. A 2021 study in Functional Ecology found that incubating female hummingbirds generally avoid torpor while on eggs, since letting body temperature crash overnight can slow embryonic development or put chicks at risk. One remarkable exception was documented directly in the scientific literature: a nesting Anna's Hummingbird went into torpor for 4.5 hours one night following a rainy day, and her eggs cooled to just 11°C (52°F) — yet still hatched successfully two days later, a testament to how much punishment a hummingbird embryo can actually tolerate.

Habitat: From Wild Chaparral to Your Own Backyard

In its original native range, Anna's Hummingbird favors chaparral with nearby broad-leaved trees, especially coast live oak, along with montane woodlands and forests at higher elevations. But the species' expanded range tells a very different habitat story: American Bird Conservancy notes that the expanded population is now mostly restricted to urban and suburban areas — meaning this hummingbird's northward and eastward growth has been, in a very real sense, a story of adapting to human landscaping rather than colonizing wild habitat.

Today, Anna's Hummingbird is common in yards, parks, residential streets, eucalyptus groves, riverside woodland, coastal scrub, oak savanna, and — everywhere it can find one — around a well-maintained feeder.

Anna's Hummingbird by Region: Where and When to Find Them

Build an Anna's Hummingbird Sanctuary in Your Own Yard

Because Anna's Hummingbird is so often a true year-round resident rather than a seasonal visitor, the single most valuable thing you can do for this species is commit to keeping your feeding station reliable through every season — including the depths of winter, when natural nectar is scarcest and a well-maintained feeder can make a real survival difference.

• Use a leak-proof, easy-to-clean feeder like the AspenPerch® Hummingbird Feeder, with a comfort perch so Anna's Hummingbirds — known to rest between sips more than some other species — can feed without hovering the whole time.
• Keep nectar fresh year-round, not just in summer — check and change it more often in winter than you'd expect, since even mild freezes can affect consistency. Pop's Nectar, with added electrolytes and calcium, supports the extra energetic demands of a bird that may be nesting as early as December.
• Add a swing near your feeder — a Pop's Original Hummingbird Swing gives a resident Anna's Hummingbird exactly the kind of perch it uses to rest, watch its territory, and sing from between feedings.
• Plant early natives. Anna's Hummingbird's unusually early nesting season means early-blooming natives matter more here than for almost any other species — red-flowering currant, native sage, and other early chaparral bloomers directly support courtship and nesting timed to December and January.
• Protect against pests without insecticide. Since insects make up a critical part of this species' diet — especially for a nesting female feeding chicks — skip pesticides entirely, and use HummGuard™ nectar tips to keep bees and wasps out of your feeder instead.

What that looks like in practice depends heavily on where you live. Attracting hummingbirds in California means planning around a December nesting season and a resident population that never leaves, while hummingbird feeding in Washington and Oregon turns on keeping nectar from freezing through a genuine winter. Down in Arizona and southern Nevada, the challenge flips entirely toward desert heat and nectar spoilage. Each guide covers local feeder timing, native plants, and planting windows — and the full 50-state guide series has the rest.

Frequently Asked Questions

Is Anna's Hummingbird the only hummingbird that sings? Among North American species, yes — males regularly produce a scratchy, buzzy song from an exposed perch, unusual behavior in a family that communicates mostly through visual display and simple chip notes.

How far north does Anna's Hummingbird live year-round? Coastal British Columbia, including Vancouver Island — giving it the northernmost year-round range of any hummingbird species in the world, a status it's only held since roughly the 1960s and 70s.

Why did Anna's Hummingbird's range expand so dramatically? Primarily the combination of widely planted non-native ornamental flowering trees (especially eucalyptus) and the rise of backyard hummingbird feeders, both of which provided reliable winter nectar in climates the species couldn't previously have survived in.

Do Anna's Hummingbirds migrate? Mostly not — most populations are year-round residents. The exception is in parts of the desert Southwest, especially Arizona, where some birds shift toward California after the breeding season and return the following spring.

Can Anna's Hummingbirds show up outside their normal range? Yes. Individual birds turn up well east of the Rockies most years, especially in fall and winter, part of a broader pattern of western hummingbirds appearing in the East. These are rare-visitor records rather than an established population — a genuine surprise when one arrives, but not a species you can expect to host outside the West.

How does Anna's Hummingbird survive freezing winter nights? Through torpor — a controlled drop in body temperature (as low as 48°F) and metabolic rate that dramatically reduces how much energy the bird needs to burn overnight.

What's the best way to attract Anna's Hummingbirds specifically? Keep a feeder up and well-maintained year-round rather than seasonally, since this is one of the only hummingbirds you can realistically expect to see in the middle of winter. Early-blooming natives like red-flowering currant also matter more here than for other species, given how early this species starts nesting.

At Pop's Birding, we believe every backyard — big or small — has room for a little more wonder. Explore our feeders, nectars, swings, and wildflower seed blends to start building your own hummingbird sanctuary today.