Editing Inca tern

{{short description|Species of bird}}
{{Use American English|date=February 2023}}

{{speciesbox
| image = Larosterna inca -Lima, Peru -adult-8.jpg
| image_caption = Inca tern at [[Lima]], Peru
| status = NT
| status_system = IUCN3.1
| status_ref = <ref name=IUCN>{{cite iucn |author=BirdLife International |date=2018 |title=Inca Tern ''Larosterna inca'' |volume=2018 |page=e.T22694834A132576903 |doi=10.2305/IUCN.UK.2018-2.RLTS.T22694834A132576903.en |access-date=17 February 2023}}</ref>
| genus = Larosterna
| parent_authority = [[Edward Blyth|Blyth]], 1852
| species = inca
| authority = ([[René Lesson|Lesson]] & [[Prosper Garnot|Garnot]], 1827)
| range_map = Larosterna inca map.svg
|range_map_caption=Range of ''L. inca''<br/>{{leftlegend|#7138C5|Year-round range|outline=gray}}{{leftlegend|#5E8DD1|Non-breeding range|outline=gray}}
}}

The ''' Inca tern''' ('''''Larosterna inca''''') is a [[Near Threatened|near-threatened]] species of [[tern]] in the subfamily [[Sterninae]] of the family [[Laridae]] (the [[gull]]s, terns, and [[Rynchops|skimmers]]).<ref name=IOC13.1>{{cite web |url=https://www.worldbirdnames.org/new/bow/gulls/ |title=Noddies, skimmers, gulls, terns, skuas, auks |website=IOC World Bird List |version =v 13.1 |editor-last1=Gill |editor-first1= F. |editor-last2=Donsker|editor-first2=D.|editor-last3=Rasmussen |editor-first3=P. |date=January 2023 |access-date=February 16, 2023 }}</ref><ref name=IUCN/> It is found along the [[Pacific Ocean|Pacific]] coasts of [[Chile]], [[Ecuador]] and [[Peru|Perú]],<ref name="SACCcountries">Remsen, J. V., Jr., J. I. Areta, E. Bonaccorso, S. Claramunt, A. Jaramillo, D. F. Lane, J. F. Pacheco, M. B. Robbins, F. G. Stiles, and K. J. Zimmer. 30 January 2023. Species Lists of Birds for South American Countries and Territories. https://www.museum.lsu.edu/~Remsen/SACCCountryLists.htm retrieved January 30, 2023</ref> and has appeared as a [[Vagrancy (biology)|vagrant]] in [[Central America]] and [[Hawaii]].<ref name=63Supp>R. Terry Chesser, Shawn M. Billerman, Kevin J. Burns, Carla Cicero, Jon L. Dunn, Blanca E. Hernández-Baños, Rosa Alicia Jiménez, Andrew W. Kratter, Nicholas A. Mason, Pamela C. Rasmussen, J. V. Remsen, Jr., Douglas F. Stotz, and Kevin Winker. "Sixty-third supplement to the American Ornithological Society's ''Check-list of North American Birds''". ''American Ornithology'' 2022, vol. 139:1-13 retrieved August 9, 2022</ref>

==Taxonomy and systematics==
The Inca tern is the sole member of its monotypic genus ''Larosterna'', and has no accepted subspecies.<ref name=IOC13.1/> Perhaps surprisingly given its highly distinct plumage, the Inca tern is not particularly [[Basal (phylogenetics)|basal]] among the terns, being more closely related to typical ''[[Sterna]]'' terns than any of the superficially much more similar genera ''[[Gelochelidon]]'', ''[[Hydroprogne]]'', ''[[Onychoprion]]'', ''[[Phaetusa]]'', or ''[[Sternula]]'' are.<ref>{{cite journal | last=Bridge | first=Eli S. | last2=Jones | first2=Andrew W. | last3=Baker | first3=Allan J. | 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 | issue=2 | date=2005 | doi=10.1016/j.ympev.2004.12.010 | pages=459–469}}</ref><ref>{{cite journal | last=Černý | first=David | last2=Natale | first2=Rossy | title=Comprehensive taxon sampling and vetted fossils help clarify the time tree of shorebirds (Aves, Charadriiformes) | journal=Molecular Phylogenetics and Evolution | volume=177 | date=2022 | doi=10.1016/j.ympev.2022.107620 | doi-access=free | page=107620 | url=https://www.biorxiv.org/content/biorxiv/early/2021/07/16/2021.07.15.452585.full.pdf | access-date=2025-02-28}}</ref>

==Description==
[[File:Larosterna inca -Lima, Peru -family-8.jpg|left|thumb|Two adults and a juvenile (left) in [[Lima]], Perú.]]
The Inca tern is roughly {{convert|39|to|42|cm|in|abbr=on}} long and weighs between {{convert|180|to|210|g|oz|abbr=on}}. Its plumage is uniquely colored among terns; adults have a mostly dark, slate-gray body, with paler underwing [[Covert feather|coverts]], and a slightly paler throat. A white stripe extends back from the base of the bill and fans out like a [[Salvador Dalí]]esque [[Moustache|mustache]] as long, satiny feathers along the side of the neck. The trailing edge of the wing (the tips of the secondaries and the three inner [[Primaries (birds)|primaries]]) are white. The tail is black, and moderately forked. The iris is brown, with legs and feet that are dark red. The bill is bright to dark red, with bare yellow skin at the base. The chicks, on hatching, are purplish-brown, progressing through brownish-gray before developing mature plumage. The chicks' bills and legs are dark and horn-colored, and gradually attain the red that adults have.<ref name=INTE-BOW>Gochfeld, M. and J. Burger (2020). Inca Tern (''Larosterna inca''), version 1.0. In Birds of the World (J. del Hoyo, A. Elliott, J. Sargatal, D. A. Christie, and E. de Juana, Editors). Cornell Lab of Ornithology, Ithaca, NY, USA. https://doi.org/10.2173/bow.incter1.01 retrieved February 17, 2023</ref><ref name=Harrison>{{cite book | last =Harrison | first =Peter | title =Seabirds: An Identification Guide | publisher =Houghton Mifflin | date =1983 | location =Boston | pages =387 | language =en | isbn =0-395-33253-2 }}</ref>

==Distribution and habitat==
The Inca tern is an inhabitant of the [[Humboldt Current]] region. It breeds from [[Lobos de Tierra]], in northern Perú, south to the [[Aconcagua River]], near [[Valparaíso]], Chile. Some disperse north into Ecuador after breeding,<ref name=INTE-BOW/><ref name=SACCcountries/> and south to the [[Puerto Montt]] area of Chile, where multiple 'research-grade' sightings with photos on the [[biodiversity]] database [[iNaturalist]],<ref>{{cite web | title=Observations | website=iNaturalist | date=2008-04-03 | url=https://www.inaturalist.org/observations?nelat=-41.46&nelng=-72.88&subview=map&swlat=-41.50&swlng=-72.96&taxon_id=4551 | access-date=2025-02-28}}</ref> including a group of four together.<ref>{{cite web | title=Inca Tern (Larosterna inca) | publisher=iNaturalist | date=2023-05-24 | url=https://www.inaturalist.org/observations/165584658 | access-date=2025-02-28}}</ref> It is a casual visitor to [[Panama|Panamá]] and [[Costa Rica]], and has also been recorded as a [[vagrancy (biology)|vagrant]] in [[Guatemala]] and Hawaii.<ref name=63Supp/> The documented Hawaiian birds, in particular, remained from March through November on the [[Hawaiian Islands|Hawaiian archipelago]].<ref name=63Supp/>

The South American Classification Committee of the [[American Ornithological Society]] treats the Inca tern's presence in [[Colombia]] as "hypothetical", due to a number of unverified or undocumented sightings.<ref name="SACCcountries" /> On iNaturalist, one 'research-grade' sighting (with photo) has been documented from the coast of [[Buenaventura, Valle del Cauca|Buenaventura]], Colombia's Isla Cascajal, dated July 2023;<ref>{{Cite web |last=INaturalist |first=Ignaranjo |date=15 July 2023 |title=Observations • iNaturalist |url=https://www.inaturalist.org/observations/174785219 |access-date=10 June 2024}}</ref> however, the species' popularity in captivity (see [[#Captivity|Captivity]] below) complicates assessment of extralimital records.

The Inca tern nests on [[Cliffed coast|sea cliffs]] and [[guano]] islands, as well as manmade structures (such as ledges under piers) and abandoned barges. It will gather with other sea and shorebirds on sandy beaches.<ref name=INTE-BOW/><ref name=Harrison/> 

==Behavior==
[[File:15-Islas Ballestas-nX-40.jpg|thumb|left|Large flocks may occur where conditions are suitable, as here on the [[Islas Ballestas]] off the Peruvian coast]]
===Movement===
The Inca tern is essentially non-[[Bird migration|migratory]], although some disperse northwards after breeding. Some rogue individuals have flown great distances.<ref name=INTE-BOW/>

===Feeding===
The Inca tern feeds primarily on small fish, such as [[anchoveta]] (''Engraulis ringens''), and also consumes [[planktonic]] [[crustacean]]s and [[offal]] or [[carrion]] in its diet. Large flocks congregate around fishing boats and will also follow the feeding patterns of [[cormorant]]s, [[sea lion]]s, and [[whale]]s and [[dolphin]]s. Feeding flocks can number over 5,000 birds. The Inca tern catches its prey mainly by [[plunge-diving]], but also picks items from the surface while flying or floating on the water.<ref name=INTE-BOW/><ref name=Harrison/>

===Breeding===
Breeding does not appear to be concentrated in any season. Eggs have been found between April and July and between October and December, and other evidence of breeding has been noted in August. It nests in a variety of sites including fissures and caves in rock cliffs, among rocks and boulders on island slopes, in abandoned petrel and penguin burrows, and on and under human structures. The clutch size is usually two eggs though sometimes one. Both sexes incubate the clutch and provision the young. The incubation period is not known; fledging occurs about four weeks after hatch and the young are fully dependent on the adults for at least a month after fledging.<ref name=INTE-BOW/>

{{birdsong|url=https://xeno-canto.org/species/Larosterna-inca |species=Inca tern|image=Zarcillo (Larosterna inca) en Isla Blanca, Chimbote 06.jpg}}
===Vocalization===
The Inca tern is most vocal at its nesting colonies. Its calls include "raucous cackling notes" and "mewing"; the latter call has been likened to that of a kitten.<ref name=INTE-BOW/><ref name=Harrison/>

==Status==
The [[IUCN]] has assessed the Inca tern as Near Threatened. It has a somewhat restricted range; its population size is not known and is believed to be decreasing. "Reproductive success is dramatically reduced during [[El Niño]] events". Human harvesting of its primary prey is a probable threat as is climate change.<ref name=IUCN/> One estimate placed its population at about 150,000 in 2011.<ref name=INTE-BOW/>

==Captivity==
[[File:Inca tern -Tokyo- 2009 9 17.webm|thumb|thumbtime=1|right|Inca terns in captivity]]
Because of its unusual plumage, the species is popular in [[zoo]]s. Escapes from captivity can occur, which leads to problems determining genuine vagrancy.<ref>{{cite web | title=Rare birds escape Lotherton Hall aviary after heavy snowfall | website=Museums Association | date=2025-01-08 | url=https://www.museumsassociation.org/museums-journal/news/2025/01/rare-birds-escape-lotherton-hall-aviary-after-heavy-snowfall/ | access-date=2025-02-28}}</ref><ref>{{cite web | title=Sighting Report | website=BirdGuides | date=2025-01-05 | url=https://www.birdguides.com/sightings/larosterna-inca/4086038/ | access-date=2025-02-28}}</ref>

==References==
{{Commons category|Larosterna inca}}
{{Wikispecies|Larosterna inca}}
{{Reflist}}

{{Charadriiformes|L.|state=collapsed}}
{{Taxonbar|from=Q839862}}

[[Category:Terns|Inca tern]]
[[Category:Birds of Peru]]
[[Category:Birds of Chile]]
[[Category:Western South American coastal birds]]
[[Category:Birds described in 1827|Inca tern]]
[[Category:Taxa named by René Lesson]]