Bird Science - Broad-tailed Hummingbird
Broad-tailed Hummingbird: A Vibrant High-altitude Species
The Broad-tailed Hummingbird (Selasphorus platycercus) is a medium-sized hummingbird that thrives in highland regions across western North America, Mexico, and Guatemala.
Known for its striking appearance and unique behaviors, this species is a fascinating subject for bird enthusiasts and researchers alike.
Physical Characteristics
Broad-tailed Hummingbirds are medium-sized, measuring about 4 inches in length with a wingspan of approximately 5.25 inches. They weigh around 3.6 grams, with females typically being slightly larger than males.
Both sexes have an iridescent green back, a white eye ring, and a rounded black tail that extends beyond their wing tips. Males are easily distinguished by their bright rose-red gorget, a vibrant throat patch that shimmers in the sunlight.
Females, on the other hand, have paler coloration, cinnamon flanks, and spotted cheeks, which are absent in males. The white eye ring is a key identification characteristic for both sexes.
Both sexes have an iridescent green back, a white eye ring, and a rounded black tail that extends beyond their wing tips. Males are easily distinguished by their bright rose-red gorget, a vibrant throat patch that shimmers in the sunlight.
Females, on the other hand, have paler coloration, cinnamon flanks, and spotted cheeks, which are absent in males. The white eye ring is a key identification characteristic for both sexes.
Communication and Sounds
Broad-tailed Hummingbirds are known for their distinct vocalizations and wing sounds. Their call is a sharp "cheet," often repeated in a series.
These birds also produce sounds using their wing beats, which serve as an important form of communication. The "wing hum" is produced during regular flight and has a frequency range of 35 to 100 Hz.
Males also produce a "wing trill" during courtship displays, creating a buzzing sound that can be heard up to 50 meters away by other males and 75 meters away by females. This trill is generated when air passes rapidly through the 9th and 10th primary feathers.
Studies have shown that males without this trill are more likely to lose their territories to more aggressive birds.
These birds also produce sounds using their wing beats, which serve as an important form of communication. The "wing hum" is produced during regular flight and has a frequency range of 35 to 100 Hz.
Males also produce a "wing trill" during courtship displays, creating a buzzing sound that can be heard up to 50 meters away by other males and 75 meters away by females. This trill is generated when air passes rapidly through the 9th and 10th primary feathers.
Studies have shown that males without this trill are more likely to lose their territories to more aggressive birds.
Taxonomy and Classification
The Broad-tailed Hummingbird belongs to the order Apodiformes and the family Trochilidae. It is a member of the "Bee group" within the Trochilidae family, which includes six species in the genus Selasphorus.
These species are characterized by their rufous plumage and colorful neck gorgets in males. The genus can be divided into two groups geographically: one in North America and the other in Central America, specifically in Costa Rica and Panama.
Other notable members of the Selasphorus genus include Allen's Hummingbird (Selasphorus sasin), Rufous Hummingbird (Selasphorus rufus), and Scintillant Hummingbird (Selasphorus scintilla).
These species are characterized by their rufous plumage and colorful neck gorgets in males. The genus can be divided into two groups geographically: one in North America and the other in Central America, specifically in Costa Rica and Panama.
Other notable members of the Selasphorus genus include Allen's Hummingbird (Selasphorus sasin), Rufous Hummingbird (Selasphorus rufus), and Scintillant Hummingbird (Selasphorus scintilla).
Habitat and Distribution
Broad-tailed Hummingbirds are primarily found in the understory or under tree canopies of pine and oak woodlands. They also frequent subalpine meadows, montane valleys, and stands of aspen or spruce.
These birds are known to forage in open areas with flowers or in grasslands among trees and shrubs. Their breeding range extends from central Montana in the north to Guatemala in the south.
While they are occasionally seen in British Columbia, there is no evidence of breeding at such northern latitudes. During the winter, Broad-tailed Hummingbirds migrate to southern Mexico and Guatemala. Some populations in these regions are sedentary and do not migrate.
These birds are known to forage in open areas with flowers or in grasslands among trees and shrubs. Their breeding range extends from central Montana in the north to Guatemala in the south.
While they are occasionally seen in British Columbia, there is no evidence of breeding at such northern latitudes. During the winter, Broad-tailed Hummingbirds migrate to southern Mexico and Guatemala. Some populations in these regions are sedentary and do not migrate.
Migration and Breeding
Broad-tailed Hummingbirds exhibit partial migration, with some populations remaining in their breeding grounds year-round. Males typically arrive at the breeding range first, followed by females.
The breeding season coincides with peak flower production, ensuring a rich food supply for the birds. Males perform aerial displays to attract females, flying high and diving while producing trill sounds with their wing feathers.
Females build nests alone, constructing a cup-shaped nest on a tree branch using spider webs and camouflaging it with lichen, moss, and tree material. The nest-building process takes about 4 to 5 days.
Females lay two white eggs, which they incubate for approximately 16 to 19 days. The chicks are altricial at hatching and take about 10 to 12 days to develop feathers. The female continues to care for the fledglings for several weeks after they leave the nest.
The breeding season coincides with peak flower production, ensuring a rich food supply for the birds. Males perform aerial displays to attract females, flying high and diving while producing trill sounds with their wing feathers.
Females build nests alone, constructing a cup-shaped nest on a tree branch using spider webs and camouflaging it with lichen, moss, and tree material. The nest-building process takes about 4 to 5 days.
Females lay two white eggs, which they incubate for approximately 16 to 19 days. The chicks are altricial at hatching and take about 10 to 12 days to develop feathers. The female continues to care for the fledglings for several weeks after they leave the nest.
Diet and Feeding Behavior
The diet of Broad-tailed Hummingbirds consists mainly of nectar from flowers and small insects. They prefer flowers that are specifically adapted to hummingbird pollination, characterized by high nectar production and tubular, red corollas.
One such flower is the Aquilegia elegantula. In addition to nectar, these birds also consume insects, which provide essential nutrients and protein.
One such flower is the Aquilegia elegantula. In addition to nectar, these birds also consume insects, which provide essential nutrients and protein.
Conservation Status
The Broad-tailed Hummingbird is currently listed as "Least Concern" on the IUCN Red List, indicating that it is not an endangered species. However, a survey conducted between 1966 and 2015 showed a 52% decline in its population.
Despite this decline, the species appears to be well-adapted to human-modified habitats, which may help mitigate some of the threats it faces. Conservation efforts continue to monitor and protect this vibrant and unique species, ensuring its survival in the diverse ecosystems it inhabits.
Despite this decline, the species appears to be well-adapted to human-modified habitats, which may help mitigate some of the threats it faces. Conservation efforts continue to monitor and protect this vibrant and unique species, ensuring its survival in the diverse ecosystems it inhabits.