Editing Common starling (section)

== Description ==
[[File:Sturnus vulgaris (Common Starling) - 20150801 17h08 (10636).jpg|thumb|left|alt=Juvenile moulting|An immature in [[Paris]], France. It has partly moulted into its first-winter plumage; however, juvenile brown plumage is prominent on its head and neck]]
The common starling is {{convert|19|–|23|cm|in|abbr=on}} long, with a wingspan of {{convert|31|–|44|cm|in|abbr=on}} and a weight of {{convert|58|–|101|g|oz|abbr=on}}.<ref name=feare183/> Among standard measurements, the [[Wing chord (biology)|wing chord]] is {{convert|11.8|to|13.8|cm|in|abbr=on}}, the [[tail]] is {{convert|5.8|to|6.8|cm|in|abbr=on}}, the [[Culmen (bird)|culmen]] is {{convert|2.5|to|3.2|cm|in|abbr=on}} and the [[Tarsus (skeleton)|tarsus]] is {{convert|2.7|to|3.2|cm|in|abbr=on}}.<ref name=feare183/> The [[plumage]] is [[iridescence|iridescent]] black, glossed purple or green, and spangled with white, especially in winter. The underparts of adult male common starlings are less spotted than those of adult females at a given time of year. The throat feathers of males are long and loose and are used in display while those of females are smaller and more pointed. The legs are stout, pinkish- or greyish-red in the breding season, and slightly darker in winter. The bill is narrow and conical with a sharp tip; in the winter it is brownish-black but in summer, females have lemon yellow beaks with pink bases while males have yellow bills with blue-grey bases. [[Moult]]ing occurs once a year in late summer after the breeding season has finished; the fresh feathers are prominently tipped white (breast feathers) or buff (wing and back feathers), which gives the bird a speckled appearance. The reduction in the spotting in the breeding season is achieved through the white feather tips largely wearing off. Juveniles are grey-brown and by their first winter resemble adults though often retaining some brown juvenile feathering, especially on the head.<ref name=bwpc>Snow & Perrins (1998) pp. 1492–1496.</ref><ref name=Coward>Coward (1941) pp. 38–41.</ref> They can usually be sexed by the colour of the [[Iris (anatomy)|irises]], rich brown in males, mouse-brown or grey in females. Estimating the contrast between the iris and the central always-dark [[pupil]] is 97% accurate in determining sex, rising to 98% if the length of the throat feathers is also considered.<ref name= smithcuthill>{{cite journal| last1= Smith | first1= E L | last2= Cuthill| first2= I C | last3= Griffiths | first3= R | last4= Greenwood | first4= V J | last5= Goldsmith | first5= A R | last6= Evans | first6= J E | year=2005 | title= Sexing Starlings ''Sturnus vulgaris'' using iris colour | journal= Ringing & Migration | volume= 22 | pages= 193–197 | url = http://blx1.bto.org/pdf/ringmigration/22_4/smith.pdf | doi= 10.1080/03078698.2005.9674332 | issue= 4| s2cid= 53669485 }}</ref><ref name= harrison1928>{{cite journal | last= Harrison | first= James M | year=1928 | title= The colour of the soft parts of the starling | journal= British Birds | volume= 22 | issue = 2 | pages= 36–37 }}</ref> The common starling is mid-sized by both starling standards and passerine standards. It is readily distinguished from most other mid-sized passerines, such as [[Thrush (bird)|thrushes]], [[icterid]]s or small [[corvid]]s, by its relatively short tail, sharp, blade-like bill, round-bellied shape and strong, sizeable (and rufous-coloured) legs. In flight, its strongly pointed wings and dark colour are distinctive, while on the ground its strange, somewhat waddling gait is also characteristic. The colouring and build usually distinguish this bird from other starlings, although the closely related [[spotless starling]] may be distinguished by the lack of pale feather tip spots in adult breeding plumage. The [[bohemian waxwing]] is structurally very similar in flight and also flies in dense flocks; it can be distinguished by being a paler reddish buff colour, marginally smaller, and also has a very different flight call.<ref name="Svensson">{{cite book | last=Svensson | first=Lars | last2=Mullarney | first2=Killian | last3=Zetterstroem | first3=Dan | title=Collins Bird Guide | publisher=William Collins | date=2023-03-16 | isbn=978-0-00-854746-2 | page=282, 384}}</ref>

Like most terrestrial starlings the common starling moves by walking or running, rather than hopping. Their flight is quite strong and direct; their triangular wings beat very rapidly, and periodically the birds glide for a short way without losing much height before resuming powered flight. When in a flock, the birds take off almost simultaneously, wheel and turn in unison, form a compact mass or trail off into a wispy stream, bunch up again and land in a coordinated fashion.<ref name=Coward/> Common starling on migration can fly at {{convert|60|–|80|km/h|mph|abbr=on}} and cover up to {{convert|1000|–|1,500|km|mi|abbr=on}}.<ref name= linz/>

[[File:Sturnus vulgaris porphyronotus, Kakpansor, Kazakhstan 2.jpg|thumb|A common starling (''S. v. porphyronotus'', in Kazakhstan) using the protractor muscles in its jaw to force apart a [[cowpat]] to search for insect larvae]]
Several terrestrial starlings, including those in the [[genus]] ''[[Sturnus]]'', have adaptations of the skull and muscles that help with feeding by probing.<ref name =feare21>Feare & Craig (1998) pp. 21–22.</ref> This adaptation is most strongly developed in the common starling (along with the [[Sturnus unicolor|spotless]] and [[white-cheeked starling]]s), where the [[Muscle protractor pterygoidei et quadrati|protractor muscles]] responsible for opening the jaw are enlarged and the skull is narrow, allowing the eye to be moved forward to peer down the length of the bill.<ref name=hbw2>del Hoyo ''et al'' (2009) pp. 665–667.</ref> This technique involves inserting the bill into the ground and opening it as a way of searching for hidden food items. Common starlings have the physical traits that enable them to use this feeding technique, which has undoubtedly helped the species spread far and wide.<ref name=feare183>Feare & Craig (1998) pp. 183–189.</ref>

In Iberia, the western Mediterranean and northwest Africa, the common starling may be confused with the closely related spotless starling, the plumage of which, as its name implies, has a more uniform colour. At close range it can be seen that the latter has longer throat feathers, a fact particularly noticeable when it sings.<ref name=hbw>del Hoyo ''et al'' (2009) p. 725.</ref>

=== Song and calls ===
[[File:Common Starling (Sturnus vulgaris) (W1CDR0001431 BD8).ogg|thumb|Chattering calls of a group]]The common starling is noisy, its [[Bird vocalisation|song]] consisting of a wide variety of both melodic and mechanical-sounding noises as part of a ritual succession of sounds. The male is the main songster and engages in bouts of song lasting for a minute or more. Each of these typically includes four varieties of song type, which follow each other in a regular order without pause. The bout starts with a series of pure-tone whistles and these are followed by the main part of the song, a number of variable sequences that often incorporate snatches of song [[Mimicry|mimicked]] from other species of bird and various naturally occurring or man-made noises. The structure and simplicity of the sound mimicked is of greater importance than the frequency with which it occurs. In some instances, a wild starling has been observed to mimic a sound it has heard only once. Each sound clip is repeated several times before the bird moves on to the next. After this variable section comes a number of types of repeated clicks followed by a final burst of high-frequency song, again formed of several types. Each bird has its own [[Musical repertoire|repertoire]] with more proficient birds having a range of up to 35 variable song types and as many as 14 types of clicks.<ref name=Feare54>{{cite journal | last= Feare | first= Chris | year= 1996| title= Studies of West Palearctic Birds: 196. Common starling ''Sturnus vulgaris'' | journal= British Birds | volume= 89 | issue = 12 | pages= 549–568 }}</ref>
[[File:Common Starling singing, Wrocław, Poland (52885951324).jpg|thumb|left| Singing ''Sturnus vulgaris'', [[Wrocław]], Poland.]]

Males sing constantly as the breeding period approaches and perform less often once pairs have bonded. In the presence of a female, a male sometimes flies to his nest and sings from the entrance, apparently attempting to entice the female in. Older birds tend to have a wider repertoire than younger ones. Those males that engage in longer bouts of singing and that have wider repertoires attract mates earlier and have greater [[reproductive success]] than others. Females appear to prefer mates with more complex songs, perhaps because this indicates greater experience or longevity. Having a complex song is also useful in defending a territory and deterring less experienced males from encroaching.<ref name=Feare54/>[[Image:Birdsinging03182006.JPG|thumb|alt=Singing adult male|Adult male singing and displaying its long throat feathers]]Along with having adaptions of the skull and muscles for singing, male starlings also have a much larger [[Syrinx (bird anatomy)|syrinx]] than females. This is due to increased muscle mass and enlarged elements of the syringeal skeleton. The male starling's syrinx is around 35% larger than its female counterpart.<ref>{{cite journal|author1=Prince, Ben |author2=Riede, Tobias |author3=Goller, Franz|year=2011|title=Sexual dimorphism and bilateral asymmetry of syrinx and vocal tract in the European starling (''Sturnus vulgaris'')|journal=Journal of Morphology|volume=272|issue=12|pages=1527–1536|doi=10.1002/jmor.11007|pmid=22076959|pmc=3928823}}</ref> However, this sexual dimorphism is less pronounced than it is in songbird species like the zebra finch, where the male's syrinx is 100% larger than the female's syrinx.<ref>{{cite journal|author1=Luine, V. |author2=Nottebohm, F. |author3=Harding, C. |author4=McEwen, B.S.|year=1980|title=Androgen affects cholinergic enzymes in syringeal motor neurons and muscle|journal=Brain Research|volume=192|issue=1|pages=89–107|doi=10.1016/0006-8993(80)91011-2|pmid=7378793|s2cid=31511959}}</ref>

Singing also occurs outside the breeding season, taking place throughout the year apart from the moulting period. The songsters are more commonly male although females also sing on occasion. The function of such out-of-season song is poorly understood.<ref name=Feare54/> Eleven other types of call have been described including a flock call, threat call, attack call, snarl call and copulation call.<ref name=H1923>Higgins ''et al'' (2006) pp. 1923–1928.</ref> The alarm call is a harsh scream, and while foraging together common starlings squabble incessantly.<ref name=Coward/> They chatter while roosting and bathing, making a great deal of noise that can cause irritation to people living nearby. When a flock of common starlings is flying together, the synchronised movements of the birds' wings make a distinctive whooshing sound that can be heard hundreds of metres away.<ref name=H1923/>