Vaux's swift | |
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In flight in Costa Rica | |
Scientific classification | |
Domain: | Eukaryota |
Kingdom: | Animalia |
Phylum: | Chordata |
Class: | Aves |
Clade: | Strisores |
Order: | Apodiformes |
Family: | Apodidae |
Genus: | Chaetura |
Species: | C. vauxi |
Binomial name | |
Chaetura vauxi (Townsend, 1839) | |
Vaux's swift (Chaetura vauxi) is a small swift native to North America, Central America, and northern South America. It was named for the American scientist William Sansom Vaux.
This is a small swift, even compared to other Chaetura species, at 10.7 to 11.2 cm (4.2 to 4.4 in) long and weighing 18 g (0.63 oz). The northern populations are slightly larger at 11.5 cm (4.5 in), probably according to the Bergmann's Rule and/or migration requirements. It has a cigar-shaped body, crescentic wings and a short bluntly squared-off tail. The head, upperparts and wings are dusky black, and the underparts, rump and tail coverts are greyish brown. The throat is paler grey, becoming whitish in northern birds. The sexes are similar, but juveniles have dusky bases to the throat feathers.
Vaux's swift breeds in highlands from southern Alaska to central California and from southern Mexico, the northern Yucatán Peninsula, to eastern Panama and northern Venezuela. The United States' populations are migratory, wintering from central Mexico south through the Central American breeding range. The resident breeding birds in the southern part of the range are sometimes considered a separate species, dusky-backed swift, Chaetura richmondi. Preferred habitats include old growth coniferous or deciduous forests consisting of coniferous and deciduous vegetation; requires large, hollow trees for nesting.
This is a gregarious species, with flocks of 30 or more birds, and often with other swift species, such as white-collared, especially at weather fronts. It flies with a mixture of stiff wing-beats and unsteady glides. It has more varied calls than others in the genus, with a mixture of chattering, buzzes, squeaks and chips.
The swift feeds in flight on flying insects, including beetles, wasps, termites and flying ants. It forages over forests and more open areas, including towns.
Vaux's swift breeds in the mountains and foothills, from southeastern Alaska and Montana to central California, mainly above 700 m (2,300 ft). It builds a cup nest of twigs and saliva on a vertical surface in a dark cavity, such as a tree hole, cliff crevice or attic. It lays three white eggs between March and July. It spends winters in the tropics.
Vaux's swift builds saucer-shaped nests of twigs or spruce and pine needles stuck to an inside surface of a hollow tree or chimney, between 20 inches and 6 feet from the bottom of the cavity. [2]
The following seven subspecies are recognized by the International Ornithological Congress as of early 2021: [3]
The former subspecies Chaetura vauxi andrei of eastern Venezuela was recognised as a distinct species, the ashy-tailed swift, by the South American Classification Committee of the American Ornithological Society (AOS) in June 2020 and the IOC in January 2021. [4] [5] [3]
A migratory population of Vaux's swifts roost each Autumn in the old brick chimney of Chapman Elementary School in Northwest Portland, Oregon. They are locally and regionally known as "Chapman swifts" in part because packing thousands of birds into a brick chimney each evening, is a visual treat that draws large crowds. [6]
These birds should not be confused with the Chapman's swift of Brazil, Columbia, Ecuador and other nations in South America; who are a different species entirely. The Portland Oregon flock is North America's largest concentration of Vaux's swifts.
Every evening from mid-August to mid-October, thousands of Vaux's swifts gather in the sky over the school, then between sunset and dark, fly into a tall brick chimney to roost for the night. Thousands of birds flock in great living tornados, then funnel into the chimney. Estimates of 1,700 to 35,000 swifts have been reported in various years. Shortly after sunset, over a period of roughly 30 minutes, they fly into the top of the brick chimney (constructed c.1925) to roost on the interior surface until they depart at sunrise. [7] The school is on the birds' migratory route to their wintering sites in southern Central America and Venezuela. [8]
The swifts attract predators, such as owls, Peregrine falcons and Cooper's hawks, as well as hundreds to thousands [7] [9] of human spectators. [10]
The birds began using the site in the early 1980s in response to the loss of much of their natural roosting habitat — old growth Douglas-fir and forest snags. [11] Vaux's swifts prefer roosting in standing hollow trees. [8]
To protect the swifts, the school stopped using its heating system during the weeks of roosting. Students and teachers wore sweaters and jackets, especially toward the end of September when classroom temperatures can drop to 50 to 60 °F (10 to 16 °C). [12] Around 2003, the Audubon Society of Portland, school fundraisers and corporate sponsors donated $60,000 [11] to $75,000 [13] for an alternate school heating system which is independent of the brick chimney. The chimney is now maintained solely for the use of the birds.
The glossy ibis is a water bird in the order Pelecaniformes and the ibis and spoonbill family Threskiornithidae. The scientific name derives from Ancient Greek plegados and Latin, falcis, both meaning "sickle" and referring to the distinctive shape of the bill.
The chimney swift is a bird belonging to the swift family Apodidae. A member of the genus Chaetura, it is closely related to both Vaux's swift and Chapman's swift; in the past, the three were sometimes considered to be conspecific. It has no subspecies. The chimney swift is a medium-sized, sooty gray bird with very long, slender wings and very short legs. Like all swifts, it is incapable of perching, and can only cling vertically to surfaces. Many fly around all day and only come down at night when roosting.
The northern rough-winged swallow is a small, migratory swallow. It is very similar to the southern rough-winged swallow, Stelgidopteryx ruficollis.
The sandhill crane is a species of large crane of North America and extreme northeastern Siberia. The common name of this bird refers to their habitat such as the Platte River, on the edge of Nebraska's Sandhills on the American Great Plains. Sandhill cranes are known to frequent the edges of bodies of water. The central Platte River valley in Nebraska is the most important stopover area for the nominotypical subspecies, the great sandhill crane, with up to 450,000 of these birds migrating through annually.
The band-rumped swift is a species of bird in subfamily Apodinae of the swift family Apodidae. It is found from Panama south through Colombia into Ecuador, east from Venezuela into the Guianas and Brazil, and on Trinidad.
The grey-rumped swift or gray-rumped swift is a species of bird in subfamily Apodinae of the swift family Apodidae. It is found in Honduras, Nicaragua, Costa Rica, and Panama; in every mainland South American country except Chile, French Guiana, Suriname, and Uruguay; in Trinidad and Tobago; and on Grenada.
The chestnut-collared swift is a species of bird in subfamily Cypseloidinae of the swift family Apodidae. It is found from Mexico and Trinidad south to Peru and Bolivia.
The short-tailed swift is a bird in the Apodidae, or swift family.
The white-throated swift is a swift of the family Apodidae native to western North America, south to cordilleran western Honduras. Its coastal range extends as far north as Northern California, while inland it has migratory populations found throughout the Great Basin and Rocky Mountain regions, ranging as far north as southern British Columbia. White-throated swifts are found in open areas near cliffs, rock faces, or man-made structures, where they roost. Swifts are social birds, and groups are often seen roosting and foraging for flying insects together.
The white-collared swift is a species of bird in the subfamily Cypseloidinae of the swift family Apodidae. It is found in Mexico, the Greater and Lesser Antilles, Trinidad, and every mainland South American country except Chile.
Chaetura is a genus of needletail swifts found in the Americas. Although they resemble swallows, the two are not at all closely related; this is instead a result of convergent evolution. Some members of Chaetura are long-distance migrants, while others are year-round residents.
Chapman's swift is a species of bird in subfamily Apodinae of the swift family Apodidae. It is found in Bolivia, Brazil, Colombia, French Guiana, Guyana, Panama, Peru, Suriname, Trinidad, Venezuela, and possibly Ecuador.
The Costa Rican swift is a species of bird in subfamily Apodinae of the swift family Apodidae. It is found in Costa Rica and Panama.
Sick's swift is a species of swift in the family Apodidae. It was previously considered conspecific with the smaller ashy-tailed swift, but a study published in 1997 found that Sick's swift was closer to the chimney swift. The English name commemorates the German-born ornithologist Helmut Sick who studied South American birds. It is a migratory species that breeds in central South America and overwinters in northern South America. The IUCN has listed it as being of "Least Concern".
The great dusky swift is a species of bird in subfamily Cypseloidinae of the swift family Apodidae. It is found in Argentina, Brazil, Paraguay, and possibly Bolivia.
The ashy-tailed swift or Andre's swift is a Vulnerable species of bird in subfamily Apodinae of the swift family Apodidae. It is endemic to northern and central Venezuela.
The Bird Alliance of Oregon (formerly Portland Audubon) is a non-profit environmental organization dedicated to bird and habitat protection across Oregon in the United States.
Amelia Rudolph Laskey was an American amateur naturalist and ornithologist noted for her contributions to the understanding of bird behavior. Though an autodidact without formal scientific training, Laskey made many original contributions to the field of ornithology and published in reputable scientific journals. Many publications refer to her as Mrs F.C. Laskey.
The Apodinae are a subfamily of swifts and contain the following species:
Because here, not just a few, but up to 30,000 birds swoop down like a tornado at dusk, funneling into this giant chimney. It's the largest concentration of Vaux's Swifts in North America and a birdwatcher's paradise.