Editing Common raven (section)

== Distribution and habitat ==
[[File:Corvus corax jouveniles.jpeg|thumb|left|Two juveniles in Iceland]]
The common raven can thrive in varied climates; it has the largest range of any member of the genus,<ref>[[#Goodwin|Goodwin]], p. 70</ref><ref name="Helm">{{cite book| last=Madge |first=Steve| author-link=Steve Madge |title=Crows and jays : a guide to the crows, jays and magpies of the world| year=1999| orig-year=1994| series=[[Helm Identification Guides]] |publisher=Christopher Helm| location=London|pages=179–181| isbn=978-0-7136-3999-5}}</ref> and one of the largest of any passerine.<ref>{{cite web|url=http://audubonportland.org/wcc/edbirds/raven|title=Common Raven|publisher=Audubon Society of Portland |year=2012|access-date=6 November 2012}}</ref> They range throughout the [[Holarctic]] from Arctic and [[temperate]] habitats in North America and Eurasia to the deserts of North Africa, and to islands in the Pacific Ocean. In the British Isles, they are more common in Scotland, Wales, western England and Ireland, having been eradicated from other areas by gamekeeping interests.<ref name="Collins"/><ref name="Holloway">{{cite book | last=Holloway | first=Simon | title=Historical Atlas of Breeding Birds in Britain and Ireland 1875-1900: 1875-1900 | publisher=Bloomsbury Publishing | publication-place=London | date=2010 | isbn=978-0-85661-094-3 | pages=390–391}}</ref> In [[Tibet]], they have been recorded at altitudes up to 5,000&nbsp;m (16,400&nbsp;ft), and as high as 6,350&nbsp;m (20,600&nbsp;ft) on [[Mount Everest]].<ref name="Helm"/><ref>{{cite journal| author=Hingston, R W G|year=1927 | title=Bird notes from the Mount Everest expedition of 1924|pages=320–329|journal=Journal of the Bombay Natural History Society |volume=32| issue=2|url=https://biodiversitylibrary.org/page/47859591}}</ref> The population sometimes known as the 'Punjab raven', part of the subspecies ''Corvus corax laurencei'' (sometimes misnamed ''C. c. subcorax''<ref name=pcr/><ref name="Shirihai"/>) occurs in the [[Sindh]] district of Pakistan and adjoining regions of northwestern India.<ref name="hbk"/><ref name=":1"/> They are generally resident within their range for the whole year. In his 1950 work, ''Grønlands Fugle'' [''Birds of Greenland''], noted ornithologist [[Finn Salomonsen]] indicated that common ravens did not overwinter in the Arctic.<ref>{{cite book| last1=Salomonsen| first1=Finn|author-link1=Finn Salomonsen| title=Grønlands Fugle [Birds of Greenland]| year=1950| location=Copenhagen| publisher=Munksgaard}}</ref> However, in Arctic Canada and Alaska, they are found year-round.<ref>{{cite web|url=http://nationalbird.canadiangeographic.ca/bird.asp?name=Common-raven&id=1022|title=Common raven (''Corvus corax'')|publisher=The National Bird Project|access-date=December 31, 2016|archive-date=September 29, 2020|archive-url=https://web.archive.org/web/20200929091750/http://nationalbird.canadiangeographic.ca/bird.asp?name=Common-raven&id=1022/|url-status=dead}}</ref><ref>{{cite web|url=http://pubs.aina.ucalgary.ca/arctic/arctic27-1-41.pdf|title=Winter Food Habits of Ravens on the Arctic Slope of Alaska|last1=Temple|first1=Stanley|author-link1=Stanley Temple|access-date=December 31, 2016|archive-date=May 24, 2011|archive-url=https://web.archive.org/web/20110524142532/http://pubs.aina.ucalgary.ca/arctic/Arctic27-1-41.pdf|url-status=dead}}</ref><ref>{{cite web|url=http://www.arctic.uoguelph.ca/cpl/Traditional/traditional/animals/raven.htm|title=Tulugaq – Raven|publisher=Canada's Arctic|access-date=December 31, 2016|archive-date=September 29, 2020|archive-url=https://web.archive.org/web/20200929091803/http://www.arctic.uoguelph.ca/cpl/Traditional/traditional/animals/raven.htm/|url-status=dead}}</ref> Young birds may disperse locally.<ref name="Goodwin. p139">[[#Goodwin|Goodwin]], p. 139</ref>

[[File:Common Ravens in Palm Desert CA.jpg|thumb|Two juvenile common ravens in Palm Desert, California]]
In the United Kingdom, the range is currently increasing after improved legal protection, but illegal persecution by [[gamekeeper]]s remains a problem in many areas.<ref name="SRSG">{{cite web | title=Raven | website=Scottish Raptor Study Group | url=https://www.scottishraptorstudygroup.org/raptors/raven/ | access-date=2024-11-28}}</ref><ref name="Peak">{{cite web | title=The Peak District Raptor Report 2016 | url=https://pdrmg.wordpress.com/wp-content/uploads/2018/03/2016-joint-report.pdf | access-date=2024-11-28}}</ref> It favours mountainous or coastal terrain, but can also be found in parks with tall trees suitable for use as habitation. Its population is at its most dense in the north and west of the country, though the species is expanding its population southwards.<ref>{{Cite web|title=Raven {{!}} Hampshire and Isle of Wight Wildlife Trust|url=https://www.hiwwt.org.uk/wildlife-explorer/birds/crows-and-shrikes/raven|access-date=2020-10-03|website=www.hiwwt.org.uk}}</ref>

Most common ravens prefer wooded areas with large expanses of open land nearby, or coastal regions for their nesting sites and feeding grounds. In some areas of dense human population, such as [[California]] in the United States, they take advantage of a plentiful food supply and have seen a surge in their numbers.<ref name=mojave/> On coasts, individuals of this species are often evenly distributed and prefer to build their nest sites along sea cliffs.<ref name="P. J. Ewins">{{Cite journal | last1 = Ewins | first1 = P. J. | last2 = Dymond | first2 = J. N. | last3 = Marquiss | first3 = M. | doi = 10.1080/00063658609476906 | title = The distribution, breeding and diet of Ravens ''Corvus corax'' in Shetland | journal = Bird Study | volume = 33 | issue = 2 | pages = 110–116 | year = 1986 | bibcode = 1986BirdS..33..110E }}</ref> Common ravens are often located in coastal regions because these areas provide easy access to water and a variety of food sources.<ref name="P. J. Ewins" /> Also, coastal regions have stable weather patterns without extreme cold or hot temperatures.

In general, common ravens live in a wide array of environments but prefer heavily contoured landscapes. When the environment changes in vast degrees, these birds will respond with a stress response. The hormone known as [[corticosterone]] is activated by the [[hypothalamic–pituitary–adrenal axis]].<ref name="John F. Cockrem">{{Cite journal | last1 = Cockrem | first1 = J. F. | doi = 10.1007/s10336-007-0175-8 | title = Stress, corticosterone responses and avian personalities | journal = Journal of Ornithology | volume = 148 | pages = 169–178 | year = 2007 | issue = S2 | bibcode = | s2cid = 9578614 }}</ref> Corticosterone is activated when the bird is exposed to stress, such as migrating great distances.