The Broad-tailed hummingbird is a medium-sized bird found in highland regions of North and Central America. Adult birds have an iridescent green back, white eye-ring and a rounded black tail projecting beyond their wing tips, from which their name was inspired. The male possesses a characteristic bright rose-red gorget. The female can be distinguished from the male by her paler coloration, cinnamon flanks, and spotted cheeks absent in the male.
Broad-tailed hummingbirds are found from Guatemala to Mexico, in the western United States and Western Canada during summer, and winter mainly in southern Mexico and Guatemala. These birds live in pine and oak or pinyon-juniper woodland and forage in open areas with flowers or in grasslands among trees and shrubs. They breed mainly in subalpine meadows, foothills, montane valleys, and strands of aspen or spruce.
Broad-tailed hummingbirds are partially migratory. Some populations spend winter in southern Mexico or Guatemala and return to their breeding area in spring. Some populations in southern Mexico and Guatemala do not migrate and are sedentary. Broad-tailed hummingbirds are solitary and very territorial birds. They are active during the day and are often seen hovering above flowers feeding on nectar. Nesting females also often catch insects on the wing. These small birds communicate with several different sounds. Their call sounds like a sharp “cheet” and is repeated “cheet cheet cheet cheet...”. Hummingbird wing beats have also been found to be a communication signal. These birds produce two different types of sound using their wing beat. The first one is a “wing hum” and is simply produced when the hummingbird flies. This type of wing beat has a sound that ranges from 35 to 100 Hz, and both sexes are able to produce it for communication. The second is “wing trills” produced mainly by males during courtship displays. The wing trill produces a buzzing sound and can be heard 50 m away by other males and 75 m away by other females. This sound is produced when air passes rapidly through the 9th and 10th primary feathers. In one experiment, birds without this wing trill lost their territory more easily to more aggressive birds.
Broad-tailed hummingbirds have a polygynandrous (promiscuous) mating system and do not form pair bonds; both males and females may mate with several partners during the breeding season. Broad-tailed hummingbirds breed when the flower production is at its peak. Males arrive first to the breeding grounds, followed by breeding females. They perform aerial displays to attract females; they fly high and dive while producing a trill sound with their wing feathers. Females usually return to their nest sites from year to year. They build their nests alone, without male help. The overall nest construction may take around 4 to 5 days. The nest has an overall cup shape and is stuck to a tree branch with spider webs, camouflaged by the addition of an external layer of lichen, moss, and tree material. The female will lay two white eggs of around 1.2-1.5 centimeters (0.47-0.59 in) in length and incubate them alone for around 16 to 19 days. Nest cup diameter increases as the chicks age. Chicks are altricial; they hatch helpless, naked and with their eyes closed. They fledge around 10 to 12 days after hatching but will stay with their mother for up to several weeks more.
Broad-tailed hummingbirds are common and widespread, however, their populations decline due to climate change that affects the breeding success and due to severe winter temperatures on the wintering grounds. Other reasons for population declines include collisions with cars, electric fences, and window strikes.
According to the What Bird resource, the total population size of the Broad-tailed hummingbird is 3,800,000 individuals. According to the All About Birds resource the total breeding population size of the species is 10 million birds. Overall, currently, Broad-tailed hummingbirds are classified as Least Concern (LC) on the IUCN Red List and their numbers today are stable.
Broad-tailed hummingbirds are important pollinators in the ecosystem they live in. While collecting nectar, birds fly from flower to flower and transfer the pollen, thus assisting in plant pollination.