Editing Arctic tern (section)

{{Short description|Bird that breeds in the Arctic and sub-Arctic and migrates to the Antarctic}}
{{About||the aircraft|Arctic Aircraft Arctic Tern|the racehorse|Arctic Tern (horse)}}
{{pp-move|small=yes}}
{{Use dmy dates|date=November 2020}}
{{Speciesbox
| status = LC
| status_system = IUCN3.1
| status_ref = <ref name="iucn status 12 November 2021">{{cite iucn |author=BirdLife International |date=2018 |title=''Sterna paradisaea'' |volume=2018 |page=e.T22694629A132065195 |doi=10.2305/IUCN.UK.2018-2.RLTS.T22694629A132065195.en |access-date=12 November 2021}}</ref>
| image = 2009 07 02 - Arctic tern on Farne Islands - The blue rope demarcates the visitors' path.JPG
| image_caption = [[Farne Islands]]
| genus = Sterna
| species = paradisaea
| authority = [[Erik Pontoppidan|Pontoppidan]], 1763<ref name="Birdlife International"/>
| range_map = Sterna paradisaea distribution and migration map.png
| range_map_caption = Range of ''S. paradisaea'' <div style="align:left;">{{leftlegend|#E10000|Breeding grounds|outline=gray}}{{leftlegend|#00FFFF|wintering grounds|outline=gray}}{{legend-line|#007E00 solid 3px|migration routes}}</div>
| synonyms = ''Sterna portlandica''<br />''Sterna pikei''
}}

The '''Arctic tern''' ('''''Sterna paradisaea''''') is a [[tern]] in the [[family (biology)|family]] [[Laridae]]. This [[bird]] has a [[:wiktionary:circumpolar|circumpolar]] breeding distribution covering the [[Arctic]] and sub-Arctic regions of Europe (as far south as [[Brittany (administrative region)|Brittany]]), Asia, and North America (as far south as [[Massachusetts]]). The [[species]] is strongly [[bird migration|migratory]], seeing two summers each year as it migrates along a convoluted route from its northern breeding grounds to the [[Antarctic]] coast for the southern summer and back again about six months later. Recent studies have shown average annual round-trip lengths of about {{convert|70900|km|abbr=on}} for birds nesting in [[Iceland]] and [[Greenland]] and about {{convert|48700|km|abbr=on}} for birds nesting in the [[Netherlands]]. These are by far the longest migrations known in the animal kingdom. The Arctic tern  nests once every one to three years (depending on its mating cycle).

Arctic terns are medium-sized birds. They have a length of {{convert|28|-|39|cm|abbr=on}} and a [[wingspan]] of {{convert|65|-|75|cm|abbr=on}}.<ref name=AAB/> They are mainly grey and white plumaged, with a red/orange beak and feet, white forehead, a black nape and crown (streaked white), and white cheeks. The grey mantle is {{convert|305|mm|abbr=on}}, and the scapulae are fringed brown, some tipped white. The upper wing is grey with a white leading edge, and the collar is completely white, as is the rump. The deeply forked tail is whitish, with grey outer webs.

Arctic terns are long-lived birds, with many reaching fifteen to thirty years of age. They eat mainly fish and small marine [[invertebrate]]s. The species is abundant, with an estimated two million individuals. While the trend in the number of individuals in the species as a whole is not known, exploitation in the past has reduced this bird's numbers in the southern reaches of its ranges.