Editing Swallow (section)

==Distribution and habitat==
The family has a worldwide [[cosmopolitan distribution]], breeding on every continent except Antarctica. One species, the [[Pacific swallow]], occurs as a breeding bird on a number of oceanic islands in the Pacific Ocean,<ref name = "Pratt">{{cite book | last = Pratt | first = H. |author2=Bruner, P |author3=Berrett, D. | title = The Birds of Hawaii and the Tropical Pacific | publisher = [[Princeton University Press]] | year = 1987 | location = Princeton | pages = 229 | isbn = 978-0-691-08402-2 | title-link = The Birds of Hawaii and the Tropical Pacific }}</ref> the [[Mascarene martin]] breeds on Reunion and Mauritius in the [[Indian Ocean]],<ref>{{cite book | last = Sinclair | first = Ian |author2=Olivier Langrand  | title = Birds of the Indian Ocean Islands | publisher = Struik | year = 2005 | pages = 118 | isbn = 978-1-86872-956-2 }}</ref> and a number of [[bird migration|migratory]] species are common vagrants to other isolated islands and even to some sub-Antarctic islands and Antarctica.<ref name="Korczak-Abshire">{{cite journal|last1=Korczak-Abshire|first1=Małgorzata|last2=Lees|first2=Alexander|last3=Jojczyk|first3=Agata|title=First documented record of barn swallow (''Hirundo rustica'') in the Antarctic|journal=Polish Polar Research|date=2001|volume=32|issue=4|pages=355–360|doi=10.2478/v10183-011-0021-9|doi-access=}}</ref> Many species have enormous worldwide ranges, particularly the barn swallow, which breeds over most of the Northern Hemisphere and winters over most of the Southern Hemisphere.
[[File:Hirundo abyssinica.jpg|thumb|left|The [[lesser striped swallow]] is a partial migrant within Africa.]] [[File:Adult Northern Rough-winged Swallow (Stelgidopteryx serripennis) in Waterville, Maine.jpg|thumb|A [[northern rough-winged swallow]] photographed in central Maine, the northeastern limit of the species' breeding range.]]
The family uses a wide range of habitats. They are dependent on flying insects, and as these are common over waterways and lakes, they frequently feed over these, but they can be found in any open habitat, including grasslands, open woodland, savanna, marshes, mangroves, and scrubland, from [[sea level]] to high alpine areas.<ref name ="HBW"/> Many species inhabit human-altered landscapes, including agricultural land and even urban areas. Land-use changes have also caused some species to expand their range, most impressively the [[welcome swallow]], which began to colonise [[New Zealand]] in the 1920s, started breeding in the 1950s, and is now a common landbird there.<ref>{{cite journal | last1 = Tarburton | first1 = M.K. | year = 1993 | title = A Comparison of the Breeding Biology of the Welcome Swallow in Australia and Recently Colonized New Zealand | journal = Emu | volume = 93 | issue = 1| pages = 34–43 | doi = 10.1071/MU9930034 | bibcode = 1993EmuAO..93...34T }}</ref>

Species breeding in temperate regions [[bird migration|migrate]] during the winter when their insect prey populations collapse. Species breeding in more tropical areas are often more sedentary, although several tropical species are partial migrants or make shorter migrations. In [[ancient history|antiquity]], swallows were thought to have [[hibernate]]d in a state of [[torpor]], or even that they withdrew for the winter under water. [[Aristotle]] ascribed hibernation not only to swallows, but also to [[Stork|storks]] and [[Kite (bird)|kites]]. Hibernation of swallows was considered a possibility even by as acute an observer as Rev. [[Gilbert White]], in his ''[[The Natural History and Antiquities of Selborne]]'' (1789, based on decades of observations).<ref>In 1878, Dr. Elliott Coues, listed titles of 182 papers dealing with the hibernation of swallows ([http://www.npwrc.usgs.gov/resource/birds/migratio/ideas.htm (USGS: Northern Prairie Wildlife Research Center) "Early ideas about migration"] {{Webarchive|url=https://web.archive.org/web/20080827023000/http://www.npwrc.usgs.gov/resource/birds/migratio/ideas.htm |date=2008-08-27 }}).</ref> This idea may have been supported by the habit of some species to roost in some numbers in dovecotes, nests and other forms of shelter during harsh weather, and some species even entering torpor.<ref name ="HBW"/> There were several reports of suspected torpor in swallows from 1947,<ref>{{cite journal|last1=Lariewski|first1=Robert C.|last2=Thompson|first2=Henry J.|title=Field Observation of Torpidity in the Violet-Green Swallow|journal=Condor|date=1965|volume=68|issue=1|pages=102–103|url=https://sora.unm.edu/sites/default/files/journals/condor/v068n01/p0102-p0103.pdf|doi=10.2307/1365178|jstor=1365178}}</ref> such as a 1970 report that [[white-backed swallow]]s in Australia may conserve energy this way,<ref>{{cite journal|last1=Serventy|first1=D. L.|title=Torpidity in the White-backed Swallow.|journal=Emu|date=1970|volume=70|issue=1|pages=27–28|url=http://www.publish.csiro.au/MU/pdf/MU970027a|doi=10.1071/mu970027a|bibcode=1970EmuAO..70...27S |url-access=subscription}}</ref> but the first confirmed study that they or any passerine entered torpor was a 1988 study on [[house martin]]s.<ref>{{cite journal|last1=Prinzinger|first1=R|last2=Siedle|first2=K|title=Ontogeny of metabolism, thermoregulation and torpor in the house martin ''Delichon u. urbica'' (L.) and its ecological significance|journal=Oecologia|date=1988|volume=76|issue=2|pages=307–312|doi=10.1007/BF00379969|pmid=28312213|bibcode=1988Oecol..76..307P|s2cid=52596}}</ref>