The Broad-tailed Hummingbird, sometimes labeled as a ‘hummingbird of subalpine meadows’ in reference to its preferred habitat, is a medium-sized hummingbird that lives mostly in the western United States and Mexico. It’s called Broad-tailed to refer to the broad, rounded tail of both males and females of the species.
The bird is known to easily adapt in cold environments. It has the ability to enter torpor, slow its heart rate and drop its body temperature.
The Broad-tailed Hummingbird grows to a length of 3.1-3.5 inches, a wingspan of 5.1 inches, and a weight of 3-4 grams.
The Broad-tailed Hummingbird has shiny green upper parts, especially the crown and back.
The adult male is distinguished for having a metallic rosy-red or iridescent pink-red throat, white belly and breast, green sides, and black tail with some red-brown outermost feathers. Its tail is also described as wide and rounded.
The adult female, on the other hand, has a white throat with iridescent green or bronze speckles. The lower parts of the bird’s body is dull whitish, with warm buff-tinged sides. The tail feathers have an interesting color combination. The central tail feathers are green, and the outer tail feathers are rust-colored at base, black in middle, and white on the outer tips. Its chin and throat are marked with dark spots. The female’s plumage closely resembles that of Allen’s and Rufous Hummingbirds.
The juvenile Broad-tailed Hummingbird looks similar to the adult female, except that it has more spotting on its throat and its tail averages more rufous at base.
The primary diet of Broad-tailed Hummingbirds is nectar from flowers, which include red columbine, Indian paintbrush, sage, and scarlet mint. Aside from these, Broad-tailed Hummingbirds are known to feed from flowers that do not typically belong in a hummingbird’s diet, such as pussy willows, currants, and glacier lilies. Saps from trees and shrubs serve as alternate food source to nectar.
They also feed on small insects, which serve as their protein source. They get them by gleaning from leaves or snatching from midair.
Distribution and Habitat
Broad-tailed Hummingbirds live in high-altitude areas of California, Mexico, and the southern and central Rocky Mountains. Their summer range extends across mountain forests and meadows in different areas in the western United States. The resident birds’ range spans from the mountain areas of northern Mexico to as far south as Guatemala. As the summer ends, the northerly birds migrate and overwinter in the range’s southern portions. The species is mostly migratory, with some resident populations in Mexico.
They live in open woodland areas, especially pinyon-juniper and pine-oak, brushy hillsides, montane scrub and thickets. Most of the time, they live in subalpine meadows and shrubby areas that are close to forests of willow, pine, fir or spruce.
During migration season, as well as winter months, they may be seen in open spaces of lowlands perching around flowering shrubs.
The bird’s northernmost range has a very cold climate, with temperatures that can drop below freezing points even in the summer. This prompts small-bodied birds like the Broad-tailed to careful select their immediate environments.
Behavior and Ecology
The only mode of mobility of Broad-tailed Hummingbirds is flying. Indeed, they hover when they forage, beating their wings at approximately 50 wing beats per second.
The Broad-tailed Hummingbird has an ability to enter torpor in order to adapt to cold nights. It slows down its metabolic state and maintains a body temperature of 12.2°C (54°F) when ambient temperatures fall below 10°C (44°F).
Some portions of the species’ breeding habitat experience thermal inversion, which happens when cold air descends into valleys at night and consequently warms the upslope areas. Because of this, the male Broad-tailed Hummingbird, which does not attend the nest, goes upslope in order to conserve heat and reduce the energy costs of thermoregulation.
Similar to other hummingbirds, Broad-tailed Hummingbirds also exhibit a dive display during courtship. They would climb to great heights, create a cricket-like wing trill, and dive back down to the females.
Being promiscuous in nature, Broad-tailed Hummingbirds mate with different individuals in a season. Also, they do not make bonds with their pairs. Indeed, aside from the actual mating itself, male Broad-tailed Hummingbirds do not participate in building the nest or caring for the young.
The females take the responsibility of building the nest for the young in 4-5 days. They build nests about 1-4 meters above the ground, usually in low, horizontal tree branches. They utilize spider webs and gossamer in constructing the thick inner cup that will form the nest. Lichens, moss, and bark fragments will cover the outside lining of the nest. This well-insulated structure reduces the nightie energy requirements of the incubating female. The finished nest has an average outside diameter of 2 inches and inner diameter size of 0.8 inches. However, as the baby hummingbird grows, the nest slowly stretches until the cup is already flattened.
The young Broad-tailed Hummingbirds fledge about 23 days after hatching.
Even though there is no known information on population trends, the popularity of hummingbird feeders is said to be contributory to the increase in population of Broad-tailed Hummingbirds. Also, the species easily adapts to human-modified habitat, and even benefited from it.
Some threats to the existence of Broad-tailed Hummingbirds are window strikes, collision with cars, and electric fences.