Editing Treeswift (section)

{{short description|Family of birds}}
{{Automatic taxobox
| name = Treeswifts
| image = Crestedtreeswift.jpg
| image_caption = [[Crested treeswift]] (''H. coronata'')
| parent_authority = [[Harry Church Oberholser|Oberholser]], 1906
| taxon = Hemiprocne
| authority = [[Christian Ludwig Nitzsch|Nitzsch]], 1829
| subdivision_ranks = Species
| subdivision = 4., see text.
}}
'''Treeswifts''' or '''crested swifts''' are a [[family (biology)|family]], the '''Hemiprocnidae''', of aerial [[near passerine]] [[bird]]s, closely related to the [[Swift (bird)|true swifts]]. The family contains a single [[genus]], '''''Hemiprocne''''', with four species. They are distributed from [[India]] and [[Southeast Asia]] through [[Indonesia]] to [[New Guinea]] and the [[Solomon Islands]].

Treeswifts are small to medium-sized swifts, ranging in length from 15 to 30&nbsp;cm. They have long wings, with most of the length coming from the length of the [[flight feather|primaries]]; their arms are actually quite short. They visibly differ from the other swifts in matters of [[plumage]], which is softer, and they have crests or other facial ornaments, and long, forked tails.<ref name=EoB/> Anatomically they are separated from the true swifts by skeletal details in the cranium and palate, the anatomy of the tarsus, and a nonreversible hind toe that is used for perching on branches (an activity in which true swifts are unable to engage). The males have [[iridescent]] mantle plumage. They also have diastataxic wings, that is they lack a fifth secondary feather unlike swifts in the Apodini, which are eutaxic.<ref>{{cite journal|title=Revision of the Classification of the Kingfishers|journal=Bull. Am. Mus. Nat. Hist.|volume=30|year= 1912|pages= 239–311|author= Miller, W. DeW.|url=http://digitallibrary.amnh.org/bitstream/handle/2246/1867/B031a22.pdf}}</ref><ref>{{cite journal|doi=10.1642/0004-8038(2002)119[0943:PAOWFT]2.0.CO;2|year=2002|volume=119|issue=4|pages=943|title=Phylogenetic Analysis of Wing Feather Taxis in Birds: Macroevolutionary Patterns of Genetic Drift?|journal=The Auk|last1=Bostwick|first1=Kimberly S|last2=Brady|first2=Matthew J}}</ref>
[[File:Moustached Treeswift (Hemiprocne mystacea).jpg|thumb|left|[[Moustached treeswift]] on its nest. Biak, [[New Guinea]].]]

The treeswifts exhibit a wide range of habitat preferences. One species, the [[whiskered treeswift]], is a species belonging to [[Old-growth forest|primary forest]]. Highly manoeuvrable, it feeds close to vegetation beneath the canopy, and only rarely ventures into secondary forests or plantations, but never over open ground. Other species are less restricted; the [[crested treeswift]] makes use of a range of habitats including humid forests and deciduous woodland, and the [[grey-rumped treeswift]] occupies almost every habitat type available from the [[mangrove]] forests to hill forests. All species feed on insects, although exact details of what prey are taken has not been studied in detail.

Nest-building responsibilities are shared by the male and female.  They lay one [[Egg (biology)|egg]] in the nest, which is glued to an open tree branch.<ref name=EoB>{{cite book |editor=Forshaw, Joseph|author= Collins, Charles T.|year=1991|title=Encyclopaedia of Animals: Birds|publisher= Merehurst Press|location=London|pages= 136|isbn= 978-1-85391-186-6}}</ref> Egg colour varies from white to grey. Little information is available about [[avian incubation|incubation]] times, but they are thought to be longer for the larger species. Chicks hatch with a covering of grey down and are fed a bolus of regurgitated food by the parents.