Blue-throated Mountain-gem

Overview

The Blue-throated Mountain-gem is among the largest hummingbirds occurring in the United States, favoring shady, humid canyons and streamside woodland in mountainous parts of the Southwest and Mexico. Its broad tail and deliberate flight style give it a somewhat different flight impression from smaller, faster hummingbird species sharing its habitat.

Males carry a rich blue throat patch that can look almost black without direct light, while both sexes show bold white stripes above and below the eye and a tail proportionally larger than that of most other hummingbirds in its range.

Feather ID Notes

The male's gorget feathers show deep blue iridescence, often looking dark until light catches them directly. The tail is the best structural clue: broad, dark, and squared with large white corner patches visible from below, larger and more conspicuous than the tail markings of similar species.

• Gorget feathers: deep blue, can appear blackish in shade
• Facial feathers: bold white stripes above and below the eye
• Tail feathers: broad and dark with prominent white corners
• Upperparts: bronze-green, relatively dull compared to gorget The combination of a large, white-cornered tail and bold facial striping helps separate this species from other large montane hummingbirds.

Plumage Details

Adult males show the blue gorget and prominent tail markings described above, while females lack the blue throat, instead showing a plain grayish throat and the same bold facial stripes and tail pattern as males. Juveniles resemble females. There is no strong seasonal plumage variation, with an annual molt maintaining feather condition.

Habitat & Range

This species favors humid, shaded canyons, streamside woodland, and pine-oak forest at moderate elevations in mountain ranges of the southwestern United States and Mexico, extending south into parts of Central America. Some populations are resident while northern edge populations withdraw southward for the winter.

Behavior & Field Notes

Blue-throated Mountain-gems feed on nectar from canyon wildflowers and readily visit hummingbird feeders, often dominating smaller species due to their larger size. They also glean small insects from foliage and spider webs. Nests are built on rock ledges or under overhangs near water, sometimes reused across seasons. Calls include a distinctive, sharp "seep" note repeated persistently while perched or foraging.