Blue-throated Mountain-gem
At a Glance
The largest hummingbird breeding in the United States. Its normal range north of Mexico is limited to canyons in a few mountains near the border. Where it occurs, it is usually conspicuous: bold and aggressive, it dominates other hummingbirds, chasing them away from its favored flowers or sugar-water feeders. The blue on the male's throat is not easily seen, but the flashy white tail corners are hard to miss as the bird flies swiftly past or hovers in the shadows.
All bird guide text and rangemaps adapted from by Kenn Kaufman漏 1996, used by permission of Houghton Mifflin Harcourt Publishing Company. All rights reserved.
Category
Hummingbirds
IUCN Status
Least Concern
Habitat
Arroyos and Canyons, Forests and Woodlands
Region
Rocky Mountains, Southwest, Texas
Behavior
Flitter, Hovering, Rapid Wingbeats
Population
2.000.000
Range & Identification
Migration & Range Maps
Probably a permanent resident over most of its range in Mexico, but most U.S. birds depart in fall. Sometimes winters at feeders in canyons in Arizona.
Description
4 1/2 -5" (11-13 cm). Blue on throat is hard to see on male, lacking on female. Best known by size, white stripe behind eye, and especially big white corners on big black tail. Female Magnificent Hummingbird similar but more mottled below, has smaller pale corners on duller tail.
Size
About the size of a Sparrow
Color
Black, Blue, Gray, Green, White
Wing Shape
Narrow, Rounded, Short
Tail Shape
Long, Rounded, Square-tipped, Wedge-shaped
Songs and Calls
A loud seep, often repeated, uttered in flight as well as when perching.
Call Pattern
Falling, Flat, Undulating
Call Type
Buzz, Chirp/Chip, Trill
Habitat
Wooded streams in canyons. In its limited range in the U.S., almost always found near flowing water in shady mountain canyons. Inhabits streamside sycamores, pine-oak woods, coniferous forest.
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Behavior
Eggs
2. White. Incubation is by female only, 17-18 days.
Young
Female alone feeds the young. Age of young at first flight is about 24-29 days. May raise up to three broods per year.
Feeding Behavior
At flowers, usually feeds while hovering, extending its bill and long tongue deep into the flower. At feeders, may either hover or perch. To catch small insects, may fly out and grab them in midair, or hover to pluck them from foliage; sometimes takes insects from spider webs.
Diet
Mostly nectar and insects. Takes nectar from flowers. Often feeds heavily on small insects and spiders, and can survive on them in dry seasons when few flowers are blooming. Will also feed on sugar-water mixtures in hummingbird feeders.
Nesting
Especially during breeding season, males perch at mid-levels in trees and call with repeated monotonous squeak. Nest site varies, may be 1-30 feet above ground, but typically well sheltered from above. May be on branch sheltered by overhanging limb, sometimes on exposed root on undercut stream bank. Also often places nest under eaves of house or under bridge. Nest may be reused, with additions, several times. Nest (built by female) is a compact cup of grasses, moss, plant fibers, spider webs. Outer covering of green moss is unique among North American hummingbird nests.
Conservation
Conservation Status
Range in U.S. may have expanded slightly in recent decades. Vulnerable to loss of habitat in Mexico.