This common summer hummingbird of the Northwest is the western species most often found in the East (in fall and winter). Note that all except (most) adult male Rufous are rarely separable in the field from Allen’s Hummingbird, so many observations are best termed “rufous/Allen’s.” In dive display (also given in migration, and by immatures) male climbs to a start point, then dives with a slanted J-form trajectory, typically followed by a short, horizontal fluttering flight before climbing to repeat the dive. Monotypic. Length 3.2–3.7"; bill 15–19 mm.
Adult males often detected by wing buzz, which, like other Selasphorus, is produced only in direct flight, not when hovering. Adult male: flame orange gorget; rufous back often has some green spotting, can be solidly green. Adult female: throat whitish with lines of bronzy-green flecks strongest at corners, and typically a central splotch of red. Immature male: resembles adult female but upperparts fresher in fall, with fine buff tips; throat usually flecked fairly heavily, and with red spots. Rectrices average narrower and with more rufous at bases, and white tips to outer rectrices narrower. Complete molt in winter produces plumage like adult male. Immature female: resembles adult female but upperparts fresher in fall, with fine buff tips; rectrices average broader; throat evenly flecked and with no (rarely a few) red spots.
Female and immature Allen’s hummingbird safely distinguished only in the hand by narrower outer rectrices relative to age and sex. Adult male Allen’s has green back (like very small percentage of Rufous). Male Allen’s display dives are U-shaped, not J-shaped, and can be given by immatures in fall and winter. Females of resident southern California subspecies of Allen’s have paler and strongly green-mottled flanks, unlike the rufous. See female and immature Broad-tailed.
Call: a fairly hard ticking or clicking tik or chik, often doubled or trebled, ch-tik or ch-ti-tik. Alarm call: a slightly squeaky buzz, tssiur or tsirr, and squeaky chippering in interactions. Adult male’s wing buzz often draws attention; stuttering ch-ch-ch-ch-chi at pullout of dive is diagnostic. Immature males make species-specific dives without the sound effects.
Status & Distribution
Breeding: northwestern North America. Common (March–July) in open woodlands and parks. Migration: mainly late February–early May, late June–September. Rare (mainly July–November) in the East. Winter: Mexico. Rare (mainly October–March) in the Southeast and southern California.
—From the National Geographic book Complete Birds of North America, 2006