Editing Roseate tern

{{Short description|Bird in the family Laridae}}
{{For|the racehorse|Roseate Tern (horse)}}
{{Speciesbox
| image = 2021-07-10 Sterna dougallii, St Marys Island, Northumberland 15.jpg
| image_caption = Nominate ''S. d. dougallii'' with all-black bill, [[Northumberland]], UK
| status = LC
| status_system = IUCN3.1
| status_ref = <ref name="iucn status 13 November 2021">{{cite iucn |author=BirdLife International |date=2018 |title=''Sterna dougallii'' |volume=2018 |page=e.T22694601A132260491 |doi=10.2305/IUCN.UK.2018-2.RLTS.T22694601A132260491.en |access-date=13 November 2021}}</ref>
| genus = Sterna
| species = dougallii
| authority = [[George Montagu (naturalist)|Montagu]], 1813
| range_map = Sterna dougallii map.svg
}}

The '''roseate tern''' ('''''Sterna dougallii''''') is a species of [[tern]] in the family [[Laridae]]. The genus name ''Sterna'' is derived from [[Old English]] "stearn", "tern",<ref name=OED>{{OED|Sterna}}</ref> and the specific ''dougallii'' refers to Scottish physician and collector Dr [[Peter McDougall (physician)|Peter McDougall]] (1777–1814).<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 | page = [https://archive.org/details/Helm_Dictionary_of_Scientific_Bird_Names_by_James_A._Jobling/page/n139 139]}}</ref> "Roseate" refers to the bird's pink breast in breeding plumage.<ref name=OED2>{{OED|Roseate}}</ref>

==Taxonomy==
English naturalist [[George Montagu (naturalist)|George Montagu]] described the roseate tern in 1813.<ref>{{ cite book | last=Montagu | first=George | author-link=George Montagu (naturalist) | year=1813 | chapter=Tern-Roseate ''Sterna dougallii'' | title=Supplement to the Ornithological Dictionary, or Synopsis of British Birds | location=Exeter, England | publisher=Printed by S. Woolmer | chapter-url=https://books.google.com/books?id=OgkAAAAAQAAJ&pg=PP458 }} The pages are not numbered.</ref> Genetically, it is most closely related to the [[white-fronted tern]] (''S. striata''), with their common ancestor a sister lineage to the [[black-naped tern]] (''S. sumatrana'').<ref name=bridge>{{cite journal |last=Bridge |first=Eli S |author2=Jones, Andrew W |author3=Baker, Allan J |year=2005 |title=A phylogenetic framework for the terns (Sternini) inferred from mtDNA sequences: implications for taxonomy and plumage evolution |journal=Molecular Phylogenetics and Evolution |volume=35 |pages=459–469 |url=http://scholar.library.csi.cuny.edu/~fburbrink/Courses/Vertebrate%20systematics%20seminar/Bridge%20et%20al%202005%20.pdf |doi=10.1016/j.ympev.2004.12.010 |pmid=15804415 |issue=2 |bibcode=2005MolPE..35..459B |url-status=dead |archive-url=https://web.archive.org/web/20110419093510/http://scholar.library.csi.cuny.edu/~fburbrink/Courses/Vertebrate%20systematics%20seminar/Bridge%20et%20al%202005%20.pdf |archive-date=2011-04-19 }}</ref>

This species has a number of geographical subspecies, differing mainly in bill colour and minor plumage details.

''S. d. dougallii '' breeds on the Atlantic coasts of Europe and North America, and [[bird migration|winters]] south to the [[Caribbean]] and west Africa. Both the European and North American populations have been in long-term decline, though active conservation measures have reversed the decline in the last few years at some colonies, most notably at [[Rockabill Island]] off the coast of Dublin, Ireland, which now holds most of the European population (about 1200 pairs).
The tropical forms ''S. d. korustes'' and ''S. d. bangsi'' are resident breeders from east Africa across the Indian Ocean to [[Japan]]. They have more red on the bill. The long-billed and short-winged ''S. d. gracilis'' breeds in [[Australia]] and [[New Caledonia]]. The north-western Indian Ocean holds populations of ''S. d. arideensis''. Some authors suggest that only three subspecies, nominate ''S. d. dougallii'', ''S. d. arideensis'', and ''S. d. gracilis'', should be retained.<ref>Gochfeld, M. & Burger, J. 1996. Family Sternidae (terns). In: Del Hoyo, J., Elliott, A A. & Sargatal, J. (Eds). Handbook of birds of the world, Vol. 3. Barcelona: Lynx Edicions. pp. 624–667.</ref><ref>Tree, AJ (2005) The known history and movements of the Roseate Tern ''Sterna dougallii'' in South Africa and the western Indian Ocean. Marine Ornithology 33:41-47 [http://www.marineornithology.org/PDF/33_1/33_1_41-47.pdf PDF]</ref>

==Description==
[[File:2020-07-18 Sterna dougallii, St Marys Island, Northumberland 19.jpg|thumb|left|Juvenile ''S. d. dougallii'' showing its scaly mantle. Northumberland, UK.]]
[[File:Sterna dougallii bangsi, Tanjung Pasir, Banten, Indonesia 1.jpg|thumb|''S. d. bangsi'' often has an all-red bill. Indonesia.]]
This is a small-medium tern, {{convert|33|-|36|cm|in|abbr=on}} long with a {{convert|67|-|76|cm|in|abbr=on}} wingspan, which can be confused with the [[common tern]], Arctic tern, and the larger, but similarly plumaged, [[Sandwich tern]]. The thin sharp bill is black, with a red base which develops through the breeding season, and is more extensive (to fully red) in the tropical and southern hemisphere subspecies. It is shorter-winged and has faster wing beats than common or Arctic tern. The upper wings are pale grey and its under parts white, and this tern looks very pale in flight, like a small Sandwich tern, although the outermost primary flight feathers darken during the summer. The adults have very long, flexible tail streamers and orange-red legs. In summer, the underparts of adults take on the pinkish tinge which gives this bird its name.

In winter, the forehead becomes white and the bill black. Juvenile roseate terns have a scaly appearance like juvenile Sandwich Terns, but a fuller black cap than that species.

==Behaviour and ecology==

===Food and feeding===
As with other ''Sterna'' terns, roseate tern feeds by plunge-diving for [[fish]], almost invariably from the sea; it is much more marine than allied terns, only rarely visiting freshwater lagoons on the coast to bathe and not fishing in fresh water. It usually dives directly, and not from the "stepped-hover" favoured by [[Arctic tern]]. The offering of fish by the male to the female is part of the courtship display.

Unusual for a tern, the roseate tern shows some kleptoparasitic behaviour, stealing [[fish]] from other seabirds, at British colonies most often from [[Atlantic puffin|puffins]]. This habit greatly increases their food-collecting ability during bad weather when fish swim deeper, out of reach of plunge-diving terns, but still within reach of the deeper-diving Puffins.

===Breeding===
This species breeds in colonies on coasts and islands, at times with other seabirds. In Australian colonies, it has been recorded nesting alongside the [[black-naped tern]] (''S. sumatrana''), [[lesser crested tern]] (''Thalasseus bengalensis''), [[greater crested tern]] (''T. bergii''), [[fairy tern]] (''Sternula nereis''), [[bridled tern]] (''Onychoprion anaethetus'') and [[silver gull]] (''Chroicocephalus novaehollandiae'').<ref name="sprat">{{cite web|url=http://www.environment.gov.au/cgi-bin/sprat/public/publicspecies.pl?taxon_id=817|title=Sterna dougallii — Roseate Tern|author=Department of the Environment |date=2015|work=Species Profile and Threats Database|publisher=Department of the Environment, Water, Heritage and the Arts, Australian Government|access-date=15 August 2015|location=Canberra, Australian Capital Territory}}</ref> It nests in a ground scrape, often in a hollow or under dense vegetation, and lays one or two (rarely three) eggs. It is less defensive of its nest and young than other white terns, often relying on [[Arctic tern|Arctic]] and [[common tern]]s in the surrounding colony to defend them. In smaller colonies, they may rarely mate with these other tern species.

The [[white-bellied sea-eagle]] (''Haliaeetus leucogaster'') and silver gull are known to prey on eggs and chicks, while the [[turnstone]] (''Arenaria interpres''), [[black rat]] (''Rattus rattus'') and [[King's skink]] (''Egernia kingii'') are suspected predators.<ref name="sprat"/>

===Vocalisations===

The call of the roseate tern is a very characteristic ''chuwit'', similar to that of the [[spotted redshank]], quite distinct from other terns.

==Conservation status==
[[File:Roseate Tern at Heron Island, Capricornia Cays National Park QLD.jpg|thumb|left|''S. d. gracilis'', [[Capricornia Cays National Park]], Queensland, Australia]]

In the late 19th century, these birds were hunted for their plumes which were used to decorate hats.  More recently, their numbers have decreased in some regions due to increased competition and predation by large [[gull]]s, whose numbers have increased in recent times.  This species, as of 2019, is one of the UK's rarest breeding seabird.<ref name="community.rspb.org.uk">{{Cite web|url=https://community.rspb.org.uk/getinvolved/wales/b/wales-blog/posts/celebrating-recent-successes-around-wales|title=Celebrating recent successes around Wales - RSPB Cymru Blog - We love Wales! - the RSPB Community|date=19 June 2019 }}</ref>

The largest European colony, accounting for more than 75% of the European population, is in Ireland, at [[Rockabill Island]], [[County Dublin]]. In 2013, 1213 pairs nested at Rockabill. The colony at [[Lady's Island Lake]], [[County Wexford]], is also of crucial importance, with 155 pairs nesting there in 2013.<ref>''Annual Report of the Irish Rare Birds Breeding Panel 2013''</ref>

With their favouring partly hidden nest sites, the provision of nestboxes has proven a dramatic conservation success, with the birds taking to them very readily. This results in greatly increased breeding productivity with the protection given to the young from predatory birds like [[European herring gull|herring gulls]]. At the UK's most important colony, on [[Coquet Island, England|Coquet Island]], [[Northumberland]], the population rose from 25 pairs 1997 to 154 pairs in 2022 after nestboxes were provided. Similar measures have been undertaken at the [[Anglesey tern colonies]] along with clearance of vegetation, in particular [[Malva arborea|Tree Mallow]].  In 2018, for the first time in more than a decade, a pair fledged two chicks on [[The Skerries, Isle of Anglesey|the Skerries, off Anglesey]] after a [[RSPB]] project over previous years involving wardening, newly designed nest boxes being placed strategically around the islands along with lures playing roseate tern calls and hand-made decoys.<ref name="community.rspb.org.uk"/>

In the UK the roseate tern has been designated for protection under the official government's national [[Biodiversity Action Plan]].  One of the main reasons given in the UK plan for threat to the species is [[global warming]], creating an alteration of vertical profile distribution for its food source fishes.  The roseate tern is one of the species to which the ''Agreement on the Conservation of African-Eurasian Migratory Waterbirds'' ([[AEWA]]) applies.

The Canadian Wildlife Service lists the roseate tern as Threatened. The U.S. Department of Interior lists the northeastern population as Endangered and the Caribbean population as Threatened.<ref>{{cite web|author1=Nisbet, Ian C. |author2=Gochfeld, Michael |author3=Burger, Joanna | url=http://bna.birds.cornell.edu/bna/species/370/articles/introduction|publisher=Cornell Lab of Ornithology| location=Ithaca, New York| work=Birds of North America Online|title= Roseate Tern|date=2014|access-date=15 August 2015}}</ref>

<gallery>
Roseate terns Palometas.jpg|Late in the breeding season, the bill base on ''S. d. dougallii'' turns red. [[Puerto Rico]].
Sterna dougallii dougallii MHNT.ZOO.2010.11.132.10.jpg|Egg of ''Sterna dougallii dougallii'' - [[Muséum de Toulouse]]
Sterna dougallii bangsi MHNT.ZOO.2010.11.132.11.jpg|Egg of ''Sterna dougallii bangsi'' - [[Muséum de Toulouse]]
</gallery>

==References==
{{Reflist}}

==External links==
{{Commons category|Sterna dougallii}}
{{Wikispecies|Sterna dougallii}}
* Roseate tern - [http://sabap2.adu.org.za/docs/sabap1/330.pdf Species text in The Atlas of Southern African Birds]
* [http://www.madeirabirds.com/roseate_tern Roseate tern: Madeira Birds]

{{Taxonbar|from=Q321293}}
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[[Category:Sterna|roseate tern]]
[[Category:Birds of Europe]]
[[Category:Birds of Macaronesia]]
[[Category:Birds of the Indian Ocean]]
[[Category:Birds of Southeast Asia]]
[[Category:Birds of Australia]]
[[Category:Birds of Melanesia]]
[[Category:Birds described in 1813|roseate tern]]
[[Category:Birds of the Dominican Republic]]
[[Category:Taxa named by George Montagu (naturalist)]]
[[Category:Articles containing video clips]]