Editing Common chiffchaff (section)

===Subspecies===
[[File:Spectrogramcollybita2.jpg|thumb|Sketch [[spectrogram]]s comparing calls of, from left to right, the subspecies ''collybita'', ''abietinus'' and ''tristis'']]
*''P. c. collybita'', the nominate form, breeds in Europe east to [[Poland]] and [[Bulgaria]], and is described below. It mainly winters in the south of its breeding range around the [[Mediterranean Sea|Mediterranean]] and in [[North Africa]].<ref name= Baker>{{cite book | last = Baker | first = Kevin |title = Warblers of Europe, Asia and North Africa (Helm Identification Guides) | year = 1997 | publisher = Helm| isbn =978-0-7136-3971-1 |pages = 256–259 | location = London| title-link = Helm Identification Guides }}</ref> It has been expanding its range northwards into Scandinavia since 1970 and close to the southern edge of the range of ''P. c. abietinus''.<ref name=Hanson>{{cite journal|last=Hansson|first=MC|author2=Bensch, S |author3=Brännström, O | url= http://lup.lub.lu.se/record/145893|title=Range expansion and the possibility of an emerging contact zone between two subspecies of Chiffchaff ''Phylloscopus collybita ssp'' |year=2000 |journal = Journal of Avian Biology |volume=31|issue=4|pages=548–558 | doi=10.1034/j.1600-048X.2000.1310414.x }}</ref>
*''P. c. abietinus'' occurs in [[Scandinavia]] and northern [[Russia]], and winters from southeastern Europe and northeastern Africa east to [[Iraq]] and western [[Iran]]. It is intermediate in appearance between ''P. c. tristis'' and ''P. c. collybita'', being grey-washed olive-green above with a pale yellow [[supercilium]], and underparts whiter than in ''P. c. collybita'',{{sfn|Clement|1995|pp=16–18}} but it has very similar vocalisations to the nominate subspecies.<ref name= Baker/> Due to individual variation, it can be difficult to reliably separate ''P. c. abietinus'' and ''P. c. collybita'' outside their main breeding and wintering ranges.{{sfn|Clement|1995|pp=16–18}} Some common chiffchaffs in the Middle East are browner and have a more disyllabic ''swee-hu'' call than ''P. c. abietinus'', and may belong to a poorly known taxon "''brevirostris''";<ref name= dubois2008>{{Cite journal | last1 = Dubois | first1 = Phillipe | last2 = Duquet | first2 = M. | year = 2008 | title = Further thoughts on Siberian Chiffchaffs | journal = British Birds | volume = 101 | pages = 149–150 }}</ref> further research is needed to clarify the affinities of this form.<ref name= dubois2010>{{Cite journal | last1 = Dubois | first1 = Phillipe | year = 2010 | title = Presumed 'brevirostris'-type Common Chiffchaffs wintering in Jordan | journal = British Birds | volume = 103 | pages = 406–407 }}</ref>
*''P. (c.) tristis'', the '''[[Siberian chiffchaff]]''', breeds in [[Siberia]] east of the [[Pechora River]] and winters in the lower [[Himalayas]].<ref name=Baker/> It is also regularly recorded in western Europe in winter, and it is likely that the numbers involved have been underestimated due to uncertainties over identification criteria, lack of good data and recording policies (Sweden and Finland only accept trapped birds).<ref name= dean8>{{Cite journal | last1 = Dean | first1 = Alan | last2 = Bradshaw | first2 = Colin | last3 = Martin | first3 = John | last4 = Stoddart | first4 = Andy | last5 = Walbridge | first5 = Grahame | year = 2010 | title = The status in Britain of 'Siberian Chiffchaff' | journal = British Birds | volume = 103 | pages = 320–337 }}</ref> It is a dull subspecies, grey or brownish above and whitish below, with little yellow in the plumage, and the buff-white supercilium is often longer than in the western subspecies. It has a higher pitched ''suitsistsuisit'' song and a short high-pitched ''cheet'' call.{{sfn|Clement|1995|pp=18–20}} It is sometimes considered to be a full species due to its distinctive plumage and vocalisations, being similar to ''P. s. sindianus'' in these respects.<ref name = Martens1983/><ref name= Helbig1996>{{Cite journal | last1 = Helbig | first1 = Andreas J. | last2 = Martens | first2 = Jochen | last3 = Seibold | first3 = I. | last4 = Henning | first4 = F. | last5 = Schottler | first5 = B | last6 = Wink | first6 = Michael | year = 1996 | title = Phylogeny and species limits in the Palearctic Chiffchaff ''Phylloscopus collybita'' complex: mitochondrial genetic differentiation and bioacoustic evidence | url = http://www.uni-heidelberg.de/institute/fak14/ipmb/phazb/pubwink/1996/13_1996.pdf | journal = [[Ibis (journal)|Ibis]] | volume = 138 | issue = 4| pages = 650–666 | doi = 10.1111/j.1474-919X.1996.tb04767.x}}</ref> Nominate ''P. c. collybita'' and ''P. c. tristis'' do not recognize each other's songs.<ref name=Schubert>{{cite journal | last1 = Schubert | first1 = M | year = 1982 | title = Zur Lautgebung mehrerer zentralasiatischer Laubsänger-Arten (''Phylloscopus''; Aves, Sylviidae) | journal = Mitteilungen aus dem Zoologischen Museum Berlin | volume = 58 | pages = 109–128 |language=de}}</ref><ref name = MartensMeincke1989>{{cite journal | last1 = Martens | first1 = Jochen | last2 = Meincke | first2 = C | year = 1989 | title = Der sibirische Zilpzalp (''Phylloscopus collybita tristis''): Gesang und Reaktion einer mitteleuropäischen Population im Freilandversuch | journal = Journal für Ornithologie | volume = 130 | issue = 4| pages = 455–473 | doi = 10.1007/BF01918465 | s2cid = 25216705 |language=de}}</ref> Pending resolution of the status of ''P. (c.) fulvescens'', which is found where the ranges of ''P. c. abietinus'' and ''P. c. tristis'' connect and may<ref name= Marova>{{cite journal | last1 = Marova | first1 = I. M. | last2 = Leonovich | first2 = V. V. | year = 1993 | title = [Hybridization between Siberian (''Phylloscopus collybita tristis'') and East European (''Ph. collybita abietinus'') Chiffchaffs in the area of sympatry.] | journal = Sbornik Trudov Zoologicheskogo Muzeya, Moskovskogo Gosudarstvennogo Universiteta | volume = 30 | pages = 147–163 |language=ru}}</ref> or may not<ref name = MartensMeincke1989/> be a hybrid between these, ''tristis'' is maintained in ''P. collybita''.<ref name = Sangster2002/>
[[File:Common Chiffchaff Khangchendzonga National Park West Sikkim India 30.03.2016.jpg|thumb|left|''Phylloscopus collybita tristis'' From [[Khangchendzonga National Park]], [[West Sikkim]], [[India]].]]