The calliope hummingbird ( ; ''Selasphorus calliope'') is the smallest

bird Birds are a group of warm-blooded vertebrates constituting the class Aves (), characterised by feathers, toothless beaked jaws, the laying of hard-shelled eggs, a high metabolic rate, a four-chambered heart, and a strong yet lightweigh ...

native to the

United States The United States of America (U.S.A. or USA), commonly known as the United States (U.S. or US) or America, is a country primarily located in North America. It consists of 50 states, a federal district, five major unincorporated territorie ...

and

Canada Canada is a country in North America. Its ten provinces and three territories extend from the Atlantic Ocean to the Pacific Ocean and northward into the Arctic Ocean, covering over , making it the world's second-largest country by tot ...

. It has a western

breeding range Species distribution —or species dispersion — is the manner in which a biological taxon is spatially arranged. The geographic limits of a particular taxon's distribution is its range, often represented as shaded areas on a map. Patterns of ...

mainly from

California California is a U.S. state, state in the Western United States, located along the West Coast of the United States, Pacific Coast. With nearly 39.2million residents across a total area of approximately , it is the List of states and territori ...

British Columbia British Columbia (commonly abbreviated as BC) is the westernmost province of Canada, situated between the Pacific Ocean and the Rocky Mountains. It has a diverse geography, with rugged landscapes that include rocky coastlines, sandy beaches, ...

, and migrates to the

Southwestern United States The Southwestern United States, also known as the American Southwest or simply the Southwest, is a geographic and cultural region of the United States that generally includes Arizona, New Mexico, and adjacent portions of California, Colorado, Ne ...

Mexico Mexico (Spanish: México), officially the United Mexican States, is a country in the southern portion of North America. It is bordered to the north by the United States; to the south and west by the Pacific Ocean; to the southeast by Guatema ...

, and

Central America Central America ( es, América Central or ) is a subregion of the Americas. Its boundaries are defined as bordering the United States to the north, Colombia to the south, the Caribbean Sea to the east, and the Pacific Ocean to the west. ...

for its wintering grounds. It was previously considered the only member of the genus ''Stellula'', but recent evidence suggests placement in the genus ''

Selasphorus ''Selasphorus'' is a genus of hummingbirds from Middle and North America. Taxonomy The genus ''Selasphorus'' was introduced in 1832 by the English naturalist William John Swainson to accommodate the rufous hummingbird which is now the type s ...

''. This bird was named after the Greek

muse In ancient Greek religion and mythology, the Muses ( grc, Μοῦσαι, Moûsai, el, Μούσες, Múses) are the inspirational goddesses of literature, science, and the arts. They were considered the source of the knowledge embodied in the ...

Calliope. The former genus name means "little star".

Description

The calliope is the smallest breeding bird found in

and the

. The only smaller species ever found in the U.S. is the

bumblebee hummingbird The bumblebee hummingbird (''Selasphorus heloisa'') is a species of hummingbird in tribe Mellisugini of subfamily Trochilinae, the "bee hummingbirds". It is endemic to Mexico, but has occurred as a vagrant in the United States. Taxonomy and ...

, an accidental vagrant from

. An adult calliope hummingbird can measure in length, span across the wings and weigh .Calliope Hummingbird, Life History, All About Birds – Cornell Lab of Ornithology
Allaboutbirds.org. Retrieved on 2012-08-22.
Imnh.isu.edu. Retrieved on 2012-08-22. Calliope hummingbirds have glossy green on the back and crown with white underparts. The adult male has wine-red streaks on the

gorget A gorget , from the French ' meaning throat, was a band of linen wrapped around a woman's neck and head in the medieval period or the lower part of a simple chaperon hood. The term later described a steel or leather collar to protect the thro ...

, green flanks and a dark tail. Females and immatures have a pinkish wash on the flanks, dark streaks on the throat and a dark tail with white tips. The only similar birds are the

rufous hummingbird The rufous hummingbird (''Selasphorus rufus'') is a small hummingbird, about long with a long, straight and slender bill. These birds are known for their extraordinary flight skills, flying during their migratory transits. It is one of nine sp ...

and the Allen's hummingbird, but these birds are larger with more distinct and contrasting rufous markings on tail and flanks, and longer central tail feathers. Calliope-nest edit

Habitat and distribution

The breeding habitat of calliope hummingbird is varied among open shrub habitats and altitudes. Nesting usually occurs at higher altitudes in the

Rocky Mountains The Rocky Mountains, also known as the Rockies, are a major mountain range and the largest mountain system in North America. The Rocky Mountains stretch in straight-line distance from the northernmost part of western Canada, to New Mexico in ...

. Nests have been observed from as low as in

Oregon Oregon () is a U.S. state, state in the Pacific Northwest region of the Western United States. The Columbia River delineates much of Oregon's northern boundary with Washington (state), Washington, while the Snake River delineates much of it ...

and

Washington Washington commonly refers to: * Washington (state), United States * Washington, D.C., the capital of the United States ** A metonym for the federal government of the United States ** Washington metropolitan area, the metropolitan area centered on ...

elevation to the

tree line The tree line is the edge of the habitat at which trees are capable of growing. It is found at high elevations and high latitudes. Beyond the tree line, trees cannot tolerate the environmental conditions (usually cold temperatures, extreme snowp ...

at over . In

Montana Montana () is a state in the Mountain West division of the Western United States. It is bordered by Idaho to the west, North Dakota and South Dakota to the east, Wyoming to the south, and the Canadian provinces of Alberta, British Columbi ...

, the minimum elevation observed for breeding is . Open montane forest, mountain meadows, and

willow Willows, also called sallows and osiers, from the genus ''Salix'', comprise around 400 speciesMabberley, D.J. 1997. The Plant Book, Cambridge University Press #2: Cambridge. of typically deciduous trees and shrubs, found primarily on moist s ...

and alder thickets may variously serve as breeding grounds. During migration and winter, they also occur in

chaparral Chaparral ( ) is a shrubland plant community and geographical feature found primarily in the U.S. state of California, in southern Oregon, and in the northern portion of the Baja California Peninsula in Mexico. It is shaped by a Mediterranean c ...

, lowland brushy areas, deserts and semi-desert regions. They nest in western

North America North America is a continent in the Northern Hemisphere and almost entirely within the Western Hemisphere. It is bordered to the north by the Arctic Ocean, to the east by the Atlantic Ocean, to the southeast by South America and the Car ...

from southern

and

Alberta Alberta ( ) is one of the thirteen provinces and territories of Canada. It is part of Western Canada and is one of the three prairie provinces. Alberta is bordered by British Columbia to the west, Saskatchewan to the east, the Northwest Ter ...

south to

Colorado Colorado (, other variants) is a state in the Mountain West subregion of the Western United States. It encompasses most of the Southern Rocky Mountains, as well as the northeastern portion of the Colorado Plateau and the western edge of t ...

and southern

. During spring and summer, they move, mainly through

Arizona Arizona ( ; nv, Hoozdo Hahoodzo ; ood, Alĭ ṣonak ) is a state in the Southwestern United States. It is the 6th largest and the 14th most populous of the 50 states. Its capital and largest city is Phoenix. Arizona is part of the Fou ...

and

New Mexico ) , population_demonym = New Mexican ( es, Neomexicano, Neomejicano, Nuevo Mexicano) , seat = Santa Fe , LargestCity = Albuquerque , LargestMetro = Tiguex , OfficialLang = None , Languages = English, Spanish ( New Mexican), Navajo, Ker ...

and northern

, to winter in southwestern

as well as in

Guatemala Guatemala ( ; ), officially the Republic of Guatemala ( es, República de Guatemala, links=no), is a country in Central America. It is bordered to the north and west by Mexico; to the northeast by Belize and the Caribbean; to the east by H ...

and

Belize Belize (; bzj, Bileez) is a Caribbean and Central American country on the northeastern coast of Central America. It is bordered by Mexico to the north, the Caribbean Sea to the east, and Guatemala to the west and south. It also shares a wate ...

Behavior

Calliope hummingbirds are a migratory bird, generally leaving their breeding grounds earlier than most birds (although not as early as the

) to take advantage of the late-summer wildflowers in the mountains of western North America. They are believed to be the smallest-bodied long distance migrant in the world. These birds feed on nectar from flowers using a long extendable tongue, drink sap from holes created by

sapsucker The sapsuckers are species of North American woodpeckers in the genus ''Sphyrapicus''. Taxonomy and systematics The genus ''Sphyrapicus'' was introduced in 1858 by the American naturalist Spencer Baird with the yellow-bellied sapsucker (''Sphyra ...

s or catch

insect Insects (from Latin ') are pancrustacean hexapod invertebrates of the class Insecta. They are the largest group within the arthropod phylum. Insects have a chitinous exoskeleton, a three-part body ( head, thorax and abdomen), three pairs ...

s on the wing. While collecting

nectar Nectar is a sugar-rich liquid produced by plants in glands called nectaries or nectarines, either within the flowers with which it attracts pollinating animals, or by extrafloral nectaries, which provide a nutrient source to animal mutualists ...

, they also assist in plant

pollination Pollination is the transfer of pollen from an anther of a plant to the stigma of a plant, later enabling fertilisation and the production of seeds, most often by an animal or by wind. Pollinating agents can be animals such as insects, birds ...

. Plants preferred for pollinating include paintbrush, penstemon, columbine, trumpet gilia, and elephant head. They will also occasionally catch and eat small

s and

spider Spiders ( order Araneae) are air-breathing arthropods that have eight legs, chelicerae with fangs generally able to inject venom, and spinnerets that extrude silk. They are the largest order of arachnids and rank seventh in total species ...

s. Adult males usually arrive on the breeding ground before females, from mid-April to early May. The male claims and vigorously defends a nesting territory in which he will breed with many females. The male takes no part in raising the young and often actually vacates the breeding grounds by the time the young hatch. The female usually builds an open cup nest in a

conifer Conifers are a group of conifer cone, cone-bearing Spermatophyte, seed plants, a subset of gymnosperms. Scientifically, they make up the phylum, division Pinophyta (), also known as Coniferophyta () or Coniferae. The division contains a single ...

tree under an overhanging branch, though apple and alder trees have also been used. The nest is often built on the base of large pine cones and somewhat resembles a pine cone itself. A nest may be used repeatedly over the course of several years. Two eggs are laid from late May to early July and are incubated for 15 to 16 days. The young are capable of flight about 20 days after hatching.

Humming

The prominent humming sound of a calliope hummingbird as for all hummingbirds during flight and hovering derives from its rapid wingbeats while feeding or interacting with other hummingbirds. Humming serves as an audible communication to alert other birds of the arrival of a fellow forager or potential mate. The humming sound derives from aerodynamic forces generated by both the downstrokes and upstrokes of the rapid wingbeats, producing acoustic oscillations and harmonics.

Courtship display and sonation

During

courtship Courtship is the period wherein some couples get to know each other prior to a possible marriage. Courtship traditionally may begin after a betrothal and may conclude with the celebration of marriage. A courtship may be an informal and private m ...

, a male calliope hummingbird hovers at accelerated wingbeat frequency up to 95 flaps per second (42% higher than normal hovering), creating a loud buzzing sound, with throat feathers protruding and facing a female. The male then ascends temporarily to 20 meters and dives at high speed, with the rapid descent causing sonation of wing and tail feathers combined with vocalization, intending to attract attention of the female. Research in a

wind tunnel Wind tunnels are large tubes with air blowing through them which are used to replicate the interaction between air and an object flying through the air or moving along the ground. Researchers use wind tunnels to learn more about how an aircraft ...

demonstrated that the male courtship display includes sounds produced by three independent feather or vocal components, each with different acoustic characteristics, thus potentially containing different messages appealing to the female. The tail feathers flutter at high frequency and hit each other to produce the buzzing sound. Pause in Flight; Calliope Hummingbird (Stellula calliope)

Pause in Flight; Calliope Hummingbird (Stellula calliope)

Temperature regulation

The high metabolic rate of calliope hummingbirds – especially during rapid forward flight and hovering – produces increased body heat that requires specialized mechanisms of temperature regulation for dissipating heat, which becomes an even greater challenge in hot, humid climates. As the smallest North American hummingbird species, calliopes appear to adapt their relatively higher

surface-to-volume ratio The surface-area-to-volume ratio, also called the surface-to-volume ratio and variously denoted sa/vol or SA:V, is the amount of surface area per unit volume of an object or collection of objects. SA:V is an important concept in science and engin ...

to improve convective cooling from air movement by the wings. When air temperatures rise above , thermal gradients driving heat passively by convective dissipation from around the eyes, shoulders, and feet are reduced or eliminated, requiring heat dissipation mainly by evaporation and exhalation. All hummingbirds dissipate heat partially by exhaled air, and from body structures with thin or no feather covering, such as around the eyes, shoulders, under the wings (

patagia The patagium (plural: patagia) is a membranous Animal body, body part that assists an animal in obtaining lift (force), lift when gliding flight, gliding or flight. The structure is found in extant taxon, extant and extinct groups of flying and g ...

), and feet. While hovering, calliope hummingbirds do not benefit from the heat loss by air convection during forward flight, except for air movement generated by their rapid wing-beat, possibly aiding convective heat loss from the extended feet.

Status

Many species of pollinators, including the calliope hummingbird, have shown decreases in certain populations. Little information is available on the overall issues that are causing these declines but possible threats include habitat loss, increased use of pesticides, and replacement of native plants by non-native plants (although, on the other hand, many hummingbirds benefit from non-native plants in gardens that provide additional food). The restricted wintering range of calliope hummingbirds makes the species more susceptible to natural disasters, diseases, or land use changes that could wipe out significant portions of the population. The calliope hummingbird has not been well studied, leaving much of its life history unknown.

References

External links

Calliope Hummingbird – ''Stellula calliope''
USGS Patuxent Bird Identification InfoCenter

– Cornell Lab of Ornithology
Calliope Hummingbird (Selasphorus calliope)
videos at the Internet Bird Collection

(with RangeMap) {{Taxonbar, from=Q27074788

calliope hummingbird The calliope hummingbird ( ; ''Selasphorus calliope'') is the smallest bird native to the United States and Canada. It has a western breeding range mainly from California to British Columbia, and migrates to the Southwestern United States, Mexic ...

Native birds of Western Canada Native birds of the Northwestern United States Native birds of the Western United States Birds of the Sierra Nevada (United States)