Blue-throated Mountain-gem

The Blue-throated Mountain-gem (Lampornis clemenciae), previously known as the Blue-throated Hummingbird, is an exceptionally large and striking hummingbird of montane environments. Native to Mexico and the mountain canyons of the southwestern United States, this species is highly prized by birdwatchers for its impressive size, bold facial markings, and spectacular azure throat. Among North American hummingbirds, it is surpassed in size only by the Rivoli's Hummingbird, making it a dramatic visitor to mountain feeders and wildflower patches. Both sexes are characterized by their hefty size, long bills, and large tails, which they frequently pump and fan in flight.

Identifying the Blue-throated Mountain-gem is relatively straightforward due to its massive size (for a hummingbird) and key plumage characteristics:

• Male: Features a brilliant, metallic blue gorget (throat) that can look dark in poor light but flashes neon-blue when catching the sun. The back is bronze-green, transitioning to a dark greyish-brown belly. Two bold white stripes frame the face: one behind the eye (postocular stripe) and one extending from the bill down the cheek.
• Female: Lacks the blue gorget, displaying a thoroughly uniform pale grey throat and underparts. However, she retains the prominent white facial stripes and dark, bronze-green back.
• Tail: In both sexes, the large, spade-shaped tail is dark blue-black with conspicuous, broad white tips on the outer three pairs of feathers. This is highly visible when the bird fans its tail in flight.

Similar Species: Rivoli's Hummingbird (Eugenes fulgens) is of similar scale but possesses a purple crown, a green throat (in males), dark underparts, and lacks the bright white tail corners of the Mountain-gem. Broad-billed and Blue-throated should not be confused as Broad-billed is much smaller, has a bright red bill, and lacks the large white tail tips.

This species is a specialist of shady, moist montane habitats. It is primarily found in pine-oak woodlands, humid mountain forests, and steep, rocky canyons with flowing streams.

• Geographic Range: It breeds throughout Mexico's highlands and extends northward into the sky islands of southeastern Arizona, southwestern New Mexico, and West Texas (especially the Chisos Mountains).
• Migration: Populations in the United States are largely migratory, heading south into Mexico for the winter, though some individuals may linger year-round at low-elevation feeders in protected canyons. Mexican populations are mostly resident, though they may move altitudinally with the seasons.

Despite its dainty family, the Blue-throated Mountain-gem is an aggressive, loud, and dominant presence.

• Vocalization: Highly vocal, it emits a piercing, repetitive high-pitched 'peep' or 'seep' call that can be heard from a significant distance. Males sing a quiet, squeaky song composed of metallic, whispering notes.
• Feeding: Feeds heavily on nectar from native flowering plants like columbine, penstemon, agave, and honeysuckle. It also consumes small insects (gnats, flies, and wasps) caught mid-air via aerial hawking, or gleaned from foliage.
• Nesting: Uniquely, females often construct nests in shaded, sheltered locations. This includes traditional branches overhanging streams, but they frequently utilize human structures such as porch eaves, wires, cabins, and under bridges. Nests are bound with spiderwebs and camouflaged with moss and lichens.