View source for Dunlin

{{Short description|Species of bird}}
{{For|the ships|USS Dunlin}}
{{Speciesbox
| status = NT
| status_system = IUCN3.1
| status_ref = <ref name="iucn status 12 November 2021">{{cite iucn |author=BirdLife International |year=2024 |title=''Calidris alpina'' |amends=2024 |page=e.T22693427A255846610 |doi=10.2305/IUCN.UK.2024-2.RLTS.T22693427A255846610.en |access-date=28 October 2024}}</ref>
| image = Dunlin (Calidris alpina) in the Delaware Bay at Heislerville Wildlife Management Area, New Jersey, USA.png
| image_caption = C. a. hudsonia in breeding plumage
| image2 = Dunlin (Calidris alpina) (W CALIDRIS ALPINA R1 C13).ogg
| image2_caption = Display song recorded in [[Cardiganshire]], Wales
| taxon = Calidris alpina
| authority = ([[Carl Linnaeus|Linnaeus]], [[10th edition of Systema Naturae|1758]])
| range_map = CalidrisAlpinaIUCNver2018 2.png
| range_map_caption = Range of ''C. alpina''{{leftlegend|#00FF00|Breeding migrant|outline=gray}} {{leftlegend|#008000|Breeding resident|outline=gray}} {{leftlegend|#007FFF|Non-breeding|outline=gray}} {{leftlegend|#00FFFF|Passage|outline=gray}} {{leftlegend|#FF00FF|Vagrant (seasonality uncertain)|outline=gray}}
| synonyms = *''Tringa alpina'' {{small|Linnaeus,&nbsp;1758}}
*''Erolia alpina'' {{small|(Linnaeus,&nbsp;1758)}}
*''Pelidna alpina'' {{small|(Linnaeus,&nbsp;1758)}}
}}

The '''dunlin''' ('''''Calidris alpina''''') is a small [[wader]] in the genus ''[[Calidris]]''. The English name is a dialect form of "dunling", first recorded in 1531–1532. It derives from ''dun'', "dull brown", with the suffix ''-ling'', meaning a person or thing with the given quality.<ref name=OED>{{Cite OED |Dunlin}}</ref>

It is a circumpolar breeder in [[Arctic]] or subarctic regions. Birds that breed in western Europe are short-distance [[bird migration|migrants]] largely staying on western and southern European and northwest African coasts; those breeding in far northern Europe and Asia are long-distance migrants, wintering south to Africa, southeast and west Asia. Birds that breed in [[Alaska]] and the Canadian Arctic migrate short distances to the Pacific and Atlantic coasts of North America, although those nesting in northern Alaska overwinter in Asia.

==Taxonomy==
The dunlin was [[Species description|formally described]] by the Swedish naturalist [[Carl Linnaeus]] in 1758 in the [[10th edition of Systema Naturae|tenth edition]] of his ''[[Systema Naturae]]'' under the [[binomial nomenclature|binomial name]] ''Tringa alpina''. Linnaeus specified the [[type location (biology)|location]] as Lapland.<ref>{{cite book | last=Linnaeus | first=Carl | author-link=Carl Linnaeus | year=1758 | title= Systema Naturae per regna tria naturae, secundum classes, ordines, genera, species, cum characteribus, differentiis, synonymis, locis | volume=1 | edition=10th | page=149 | publisher=Laurentii Salvii | location=Holmiae (Stockholm) | language=Latin | url=https://www.biodiversitylibrary.org/page/727056 }}</ref> This species was formerly placed (with the other "[[stint]]s") by some American authors in the genus ''Erolia'',<ref>{{ cite book | editor-last=Peters | editor-first=James Lee | editor-link=James L. Peters | year=1934 | title=Check-List of Birds of the World | volume=2 | publisher=Harvard University Press | place=Cambridge, Massachusetts  | page=286 | url=https://www.biodiversitylibrary.org/page/14483099}}</ref><ref>{{Cite journal | author=Committee on Classification and Nomenclature | date=1973 | title=Thirty-Second Supplement to the American Ornithologists' Union Check-List of North American Birds | journal=Auk | volume=90 | issue=2 | pages=411–419 [415] | url=https://sora.unm.edu/node/22371 }}</ref> but is now placed with 23 other sandpipers in the genus ''[[Calidris]]'' that was introduced in 1804 by the German naturalist [[Blasius Merrem]].<ref>{{ cite journal | last=Merrem | first=Blasius | author-link=Blasius Merrem | date=8 June 1804 | title=Naturgeschichte | language=German | journal=Allgemeine Literatur-Zeitung | volume=168 | at=Col. 542 | url=https://digipress.digitale-sammlungen.de/view/bsb10502034_00451_u001/1 }} Published anonymously.</ref><ref name=ioc>{{cite web| editor1-last=Gill | editor1-first=Frank | editor1-link=Frank Gill (ornithologist) | editor2-last=Donsker | editor2-first=David | editor3-last=Rasmussen | editor3-first=Pamela | editor3-link=Pamela Rasmussen | date=2023 | title=Sandpipers, snipes, coursers | work=IOC World Bird List |version= V 13.2 | url=https://www.worldbirdnames.org/bow/sandpipers/ | publisher=International Ornithologists' Union | access-date=2 January 2024}}</ref> The genus name is from [[Ancient Greek]] ''kalidris'' or ''skalidris'', a term used by [[Aristotle]] for some grey-coloured waterside birds. The specific ''alpina '' is from [[Latin]] and means "of high mountains", in this case referring to [[alpine tundra]] habitats generally, rather than the [[Alps]] specifically.<ref name=job>{{cite book | last= Jobling | first= James A | year= 2010| title= The Helm Dictionary of Scientific Bird Names | url= https://archive.org/details/Helm_Dictionary_of_Scientific_Bird_Names_by_James_A._Jobling | publisher=Christopher Helm | location = London | isbn = 978-1-4081-2501-4 | pages=[https://archive.org/details/Helm_Dictionary_of_Scientific_Bird_Names_by_James_A._Jobling/page/n84 84], [https://archive.org/details/Helm_Dictionary_of_Scientific_Bird_Names_by_James_A._Jobling/page/n42 42]}}</ref>

Ten [[subspecies]] are recognised:<ref name=ioc/>
*''C. a. arctica'' <small>(Schiøler, 1922)</small> — breeds in northeast [[Greenland]]. Smallest subspecies, short-billed; silvery upperparts with minimal rufous; small black belly patch.<ref name="subalpinebirding">{{cite web |last1=Rodríguez Lázaro |first1=Guillermo |last2=López-Velasco |first2=Daniel |title=Unprecedented spring arrival of Greenland Dunlin ssp. arctica to Northern Spain and a first approach to its identification |url=https://subalpinebirding.com/blog/greenland-dunlin-ssp-arctica-a-first-approach-to-its-identification |website=subalpinebirding |access-date=2024-07-29}}</ref>
*''C. a. schinzii'' <small>([[Christian Ludwig Brehm|Brehm]] & Schilling, 1822)</small> — breeds in southeast Greenland, Iceland, the [[British Isles]], southern [[Scandinavia]] & [[Baltic region|the Baltic]]. Browner upperparts; small black belly patch.<ref name="subalpinebirding"/>
*''C. a. alpina'' <small>([[Carl Linnaeus|Linnaeus]], 1758)</small> — breeds in northern Scandinavia, [[Svalbard]], and northwest [[Siberia]]
*''C. a. centralis'' <small>([[Sergei Buturlin|Buturlin]], 1932)</small> — breeds in north-central and northeast Siberia
*''C. a. sakhalina'' <small>([[Louis Pierre Vieillot|Vieillot]], 1816)</small> — breeds in eastern [[Russia]] to the [[Chukchi Peninsula]]
*''C. a. kistchinski'' <small>Tomkovich, 1986</small> — breeds around the [[Sea of Okhotsk]] to [[Kuril Islands]] and [[Kamchatka]]
*''C. a. actites'' <small>Nechaev & Tomkovich, 1988</small> — breeds on [[Sakhalin]]
*''C. a. arcticola'' <small>([[W. E. Clyde Todd|Todd]], 1953)</small> — breeds from northwest Alaska to northwest Canada
*''C. a. pacifica'' <small>([[Coues]], 1861)</small> — breeds in western and southern Alaska
*''C. a. hudsonia'' <small>([[W. E. Clyde Todd|Todd]], 1953)</small> — breeds in central Canada

==Description==
{{multiple image
|align =  right
|direction = vertical
|width = 200
|image1 = Winter dunlin.png
|caption1 = Dunlin in winter plumage, Barnegat Inlet, New Jersey
}}

'''Measurements''':<ref>{{cite book | editor1-last=Cramp | editor1-first=Stanley | editor1-link=Stanley Cramp | year=1983 | chapter=''Calidris alpina'' Dunlin | title=Handbook of the Birds of Europe the Middle East and North Africa. The Birds of the Western Palearctic | volume=III: Waders to Gulls | location=Oxford | publisher=Oxford University Press | isbn=978-0-19-857506-1 | pages=356–371 }}</ref>

* '''Length''': {{cvt|16|-|20|cm|in}}
* '''Weight''': {{cvt|34|-|77|g|frac=8}}
* '''Wingspan''': {{cvt|38|-|43|cm|in}}

An adult dunlin in breeding plumage shows the distinctive black belly which no other similar-sized wader possesses. In winter, dunlins are grayish-brown above and white below. Juveniles are brown above with two weak whitish "V" shapes on the back, though less obvious than the same feature on [[little stint]] and some other species in the genus. They usually have black marks on the flanks or belly. All ages show a narrow white wingbar in flight. The legs and slightly decurved bill are black. The subspecies differ mainly in the extent of rufous plumage and the size of the black belly patch in the breeding season, and the bill length; in winter there are no subspecific distinctions in the plumage, with only the bill length providing a limited guide. Bill length varies between sexes, the females having longer bills than the males, further complicating winter subspecies identification. On the tip of the Dunlin's bill is a soft covering that fills with blood and with many nerve endings, forming a sensitive probe that is used to locate invertebrate prey in mud and sand. Although the bill can look sharp-pointed in dead specimens, in life it is blunt.<ref>{{cite book|title=The Inner Bird: Anatomy and Evolution|first=Gary W.|last=Kaiser|year=2007|publisher=UBC Press|page=24|isbn=978-0-7748-1344-0}}</ref>

The call is a typical sandpiper "chreep", and the display song a harsh trill.

==Distribution and habitat==
Dunlin are small migratory waders, however they show strong philopatry with individuals of the southern subspecies ''Calidris alpina schinzii'' in Sweden and Finland returning to, or very close to, their natal patches. [[Habitat fragmentation]] has reduced the availability of habitat patches to these birds through reducing patch size and increasing patch isolation. This reduced connectivity between patches has reduced the movements of Dunlin leaving them more susceptible to inbreeding in these locations.<ref name=Pakanen>{{cite journal |author1=Pakanen, V.-M. |author2=Koivula, K.| author3=Flodin, L.-Å. |author4=Grissot, A. | author5=Hagstedt, R. |author6=Larsson, M. |author7=Pauliny, A.| author8=Rönkä, N. |author9=Blomqvist, D. |  year=2017| title=Between-patch natal dispersal declines with increasing natal patch size and distance to other patches in the endangered Southern Dunlin ''Calidris alpina schinzii'' | journal=Ibis| volume=159| pages=611–622| doi=10.1111/ibi.12463| issue=3| doi-access=free}}</ref>

[[File:Calidris alpina migrations.png|thumb|center|750px|Distribution of subspecies, migration routes, and major European wintering sites]]

==Behaviour==
The dunlin is highly gregarious in winter, sometimes forming large flocks on coastal mudflats or sandy beaches. Large numbers can often be seen swirling in synchronized flight on stop-overs during migration or on their winter habitat.

This bird is one of the most common waders throughout its breeding and wintering ranges, and it is the species with which other waders tend to be compared. At {{convert|17|–|21|cm|in|abbr=on}} length and with a {{convert|32|–|36|cm|in|abbr=on}} [[wingspan]], it is similar in size to a [[common starling]], but stouter, with a longer, thicker bill.

The dunlin moves along the coastal mudflat beaches it prefers with a characteristic "sewing machine" feeding action, methodically picking small food items. [[Insect]]s form the main part of the dunlin's diet on the nesting grounds; it eats [[mollusca|molluscs]], [[worm]]s and [[crustacean]]s in coastal areas.

[[File:Calidris alpina MWNH 0158.JPG|thumb|Eggs, Collection [[Museum Wiesbaden]], Germany]]

===Breeding===
The nest is a shallow scrape on the ground lined with vegetation, into which typically four eggs are laid and [[avian incubation|incubated]] by the male and female parents. Chicks are [[Precociality and altriciality|precocial]], but are brooded during early development. They start to fly at approximately three weeks of age. The majority of brood care is provided by the male, as the female deserts the brood and often leaves the breeding area.

Apparent [[hybrid (biology)|hybrids]] between this species and the [[white-rumped sandpiper]] as well as with the [[purple sandpiper]] have been reported from the Atlantic coasts of North America<ref name=McLaughlin2000/><ref name=Wilson/> and Europe,<ref name=Millington1994/> respectively.

==Status==
The dunlin has an extremely large range and although the population appears to be decreasing, the population is still very large. The [[International Union for Conservation of Nature]] (IUCN) has judged that the threat to the species is of "[[Least-concern species|Near Threatened]]".<ref name="iucn status 12 November 2021"/> The dunlin is one of the species to which the ''Agreement on the Conservation of African-Eurasian Migratory Waterbirds'' ([[AEWA]]) applies.<ref>{{ cite web | title=Species| url=https://www.unep-aewa.org/en/species | publisher=Agreement on the Conservation of African-Eurasian Migratory Waterbirds (AEWA) | access-date=14 November 2021}}</ref> The southern subspecies ''C. a. schinzii'' is of particular concern, declining and endangered in some areas, particularly towards the southern edge of its range;<ref name=Pakanen/> in Denmark, only 95 pairs were left in 2021, compared to 50,000 pairs a century earlier.<ref name="DOF">{{cite web |last1=DOF Birdlife |title=Danmarks Fugle - Almindelige Ryle |url=https://dofbasen.dk/danmarksfugle/art/05120 |website=Fakta om Fugle |publisher=Dansk Ornitologisk Forening |access-date=27 July 2024 |language=Danish}}</ref> The northeast Greenland subspecies ''C. a. arctica'' is also endangered, with a very small population.<ref name="subalpinebirding"/>

==Gallery==
<gallery mode="packed" heights="110" style="font-size:100%; line-height:130%">
File:Alpenstrandläufer (calidris alpina) - Spiekeroog, Nationalpark niedersächsisches Wattenmeer.jpg|''C. a. alpina'' in breeding plumage on spring migration, [[Spiekeroog]], northern Germany
File:Calidris alpina pibydd y mawn.jpg|Bird near the end of post-juvenile moult to first-winter plumage, Wales
File:Kärrsnäppa - (Calidris alpina).jpg|Flock in [[Ystad]], Sweden
File:Seasonal-Variations-in-the-Diet-and-Foraging-Behaviour-of-Dunlins-Calidris-alpina-in-a-South-pone.0081174.s001.ogv|Foraging
</gallery>

==References==
{{Reflist|refs=
<ref name=McLaughlin2000>{{cite journal |last1=McLaughlin |first1=K.A. |last2=Wormington |first2=A. |year=2000 |title=An apparent Dunlin × White-rumped Sandpiper hybrid |journal=Ontario Birds |volume=18 |issue=1 |pages=8–12 |url=http://www.ofo.ca/site/download/id/113 |access-date=2016-03-21 |archive-date=2016-12-21 |archive-url=https://web.archive.org/web/20161221054109/http://www.ofo.ca/site/download/id/113 |url-status=dead }}</ref>

<ref name=Millington1994>{{cite journal |last=Millington |first=Richard |author-link=Richard Millington |year=1994 |title=A mystery Calidris at Cley |journal=[[Birding World]] |volume=7 |issue=2 |pages=61–63 |url=http://www.birdingworld.freeserve.co.uk/CleyCalidrisArticle.htm |archive-date=17 June 2004 |archive-url=https://web.archive.org/web/20040617170807/http://www.birdingworld.freeserve.co.uk/CleyCalidrisArticle.htm}}</ref>

<ref name=Wilson>{{cite web |first=Angus |last=Wilson |url=http://www.oceanwanderers.com/WayneRichardson.Sandpiper.html |website=Ocean Wanderers |title=A putative hybrid white-rumped sandpiper × dunlin from the east coast of the USA |access-date=11 October 2006}}</ref>
}}

==External links==
{{Commons category|Calidris alpina}}
{{Wikispecies|Calidris alpina}}
* {{BirdLife|22693427|Calidris alpina}}
* {{Avibase|name=Calidris alpina}}
* {{InternetBirdCollection|dunlin-calidris-alpina}}
* [http://www.birds.cornell.edu/AllAboutBirds/BirdGuide/Dunlin.html Dunlin Species Account] - Cornell Lab of Ornithology
* [http://www.mbr-pwrc.usgs.gov/id/framlst/i2430id.html Dunlin - ''Calidris alpina''] - USGS Patuxent Bird Identification InfoCenter
* [https://web.archive.org/web/20141202062115/http://aulaenred.ibercaja.es/wp-content/uploads/188_DunlinCalpina.pdf Ageing and sexing (PDF; 1.6 MB) by Javier Blasco-Zumeta & Gerd-Michael Heinze]
* {{VIREO|Dunlin}}
* {{IUCN_Map|22693427/255846610|Calidris alpina}}
* {{Xeno-canto species|Calidris|alpina|Dunlin}}
* {{field guide birds of the world|Calidris alpina}}
* {{ARKive}}

{{Scolopacidae|1}}
{{Taxonbar|from=Q26650}}
{{Authority control}}

[[Category:Calidris]]
[[Category:Birds of the Arctic]]
[[Category:Holarctic birds]]
[[Category:Birds of the Dominican Republic]]
[[Category:Birds of the Caribbean]]
[[Category:Birds of North Africa]]
[[Category:Birds described in 1758]]
[[Category:Taxa named by Carl Linnaeus]]
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