{{short description|Species of bird}} {{speciesbox | image = Australian Tern, Cairns, Queensland 3.jpg | image_caption = Australian tern at Cairns, Queensland | status = LC | status_system = IUCN3.1 | status_ref = <ref name="iucn status 18 November 2021">{{cite iucn |author=BirdLife International |date=2018 |title=''Gelochelidon macrotarsa'' |volume=2018 |article-number=e.T62026537A132671766 |doi=10.2305/IUCN.UK.2018-2.RLTS.T62026537A132671766.en |access-date=18 November 2021}}</ref> | genus = Gelochelidon | species = macrotarsa | authority = (Gould, 1837) }}
The '''Australian tern''' or '''Australian gull-billed tern''' ('''''Gelochelidon macrotarsa''''') is a tern in the family Laridae, native to Australia. The genus name is from Ancient Greek ''gelao'', "to laugh", and ''khelidon'', "swallow".
==Taxonomy== John Gould described ''Sterna macrotarsa'' from a specimen held at King's College, London in 1837.<ref>{{cite journal |last1=Gould |first1=John |journal=Proceedings of the Zoological Society of London |date=1837 |volume=5 |pages=24=35 [26] |url=https://www.biodiversitylibrary.org/page/30570911 | title=Characters of New Species of Australian Birds}}</ref> Although first described as a species, throughout most of the 20th and early 21st centuries it was generally considered to be a subspecies of the gull-billed tern,<ref name="HBW">{{cite book | last1=Hoyo | first1=Josep del | last2=Elliott | first2=Andrew | last3=Sargatal | first3=Jordi | title=Handbook of the Birds of the World: Hoatzin to auks | publisher=Lynx Edicions | publication-place=Barcelona | date=1992 | isbn=84-87334-20-2 | language=de | page=645}}</ref> but was re-elevated to species status by the IOC World Bird List in 2019 in its Version 9.2.<ref name="IOC2019">{{cite web | title=Noddies, gulls, terns, auks « IOC World Bird List | date=2019-08-08 | url=https://www.worldbirdnames.org/bow/gulls/ | archive-url=https://web.archive.org/web/20190623200847/https://www.worldbirdnames.org/bow/gulls/ | archive-date=2019-06-23 | url-status=unfit | access-date=2025-03-23}}</ref>
==Description== This is a fairly large and powerful tern, similar in size and general appearance to a Sandwich tern, but the short thick gull-like bill, broad wings, long legs and robust body are distinctive. The summer adult has pale grey upperparts, white underparts, a black cap, strong black bill and black legs. The call is a characteristic ''ker-wik''. It is {{convert|33|-|42|cm|in|abbr=on}} in length and {{convert|76|-|91|cm|in|abbr=on}} in wingspan.<ref name=Cornell/><ref name=planetofbirds/> Its weight ranges from {{convert|150|-|292|g|oz|abbr=on}}.<ref name=CRC/> It differs from the closely related gull-billed tern in being slightly larger, paler grey above, and with an obviously larger, heavier bill.<ref name="Rogers">{{cite journal | last1=Rogers | first1=Danny I. | last2=Collins | first2=Peter | last3=Jessop | first3=Rosalind E. | last4=Minton | first4=Clive D. T. | last5=Hassell | first5=Chris J. | title=Gull-billed Terns in north-western Australia: subspecies identification, moults and behavioural notes | journal=Emu - Austral Ornithology | volume=105 | issue=2 | date=2005 | issn=0158-4197 | doi=10.1071/MU04045 | pages=145–158}}</ref>
In winter, the cap is lost, and there is a dark patch through the eye like a Forster's tern or a Mediterranean gull. Juvenile Australian terns have a fainter mask, but otherwise look much like winter adults.
==Range== It breeds in Australia, with some also reaching New Guinea in the non-breeding season.
==Life history== This species breeds in colonies on lakes, marshes and coasts. It nests in a ground scrape and lays two to five eggs.
This is a somewhat atypical tern, in appearance like a ''Sterna'' tern, but with feeding habits more like the ''Chlidonias'' marsh terns, black tern and white-winged tern.
The Australian tern does not normally plunge dive for fish like the other white terns, and has a broader diet than most other terns. It largely feeds on insects taken in flight, and also often hunts over wet fields and even in brushy areas, to take amphibians and small mammals.<ref name=Cornell/> It is also an opportunistic feeder, and has been observed to pick up and feed on dead dragonflies from the road.<ref name=Sivakumar2004/>
==Gallery== <gallery> File:Gull-billed Tern with 3 Australian Terns, Jam Jerrup, Victoria, Australia.jpg|Three Australian terns, all in breeding plumage, with a winter plumage gull-billed tern, at Jam Jerrup, Victoria, Australia. File:Gelochelidon nilotica Karratha Western Australia 1.jpg File:Gelochelidon nilotica macrotarsa at Fivebough Wetlands.jpg File:Australian Tern (Gelochelidon macrotarsa), Brisbane, Australia.jpg </gallery>
==References== {{Reflist|refs=
<ref name=Cornell>{{Cite AllAboutBirds|Gull-billed Tern}}</ref>
<ref name=planetofbirds>{{cite web |url=http://www.planetofbirds.com/charadriiformes-sternidae-gull-billed-tern-gelochelidon-nilotica |title=Gull billed Tern (''Gelochelidon nilotica'') |year=2011 |website=Planet of Birds |access-date=2019-06-23 |archive-url=https://web.archive.org/web/20190623141442/http://www.planetofbirds.com/charadriiformes-sternidae-gull-billed-tern-gelochelidon-nilotica |archive-date=2019-06-23 }}</ref>
<ref name=CRC>{{cite book |title=CRC Handbook of Avian Body Masses |editor-first=John B. Jr. |editor-last=Dunning |publisher=CRC Press |year=1992 |isbn=978-0-8493-4258-5}}</ref>
<ref name=Sivakumar2004>{{cite journal |first=S. |last=Sivakumar |year=2004 |title=Gull-billed Tern Gelochelidon nilotica (Gmelin, 1789) feeding on insect road kills |journal=Newsletter for Ornithologists |volume=1 |issue=1–2 |pages=18–19 |url=http://www.birdwatching.co.in/Old%20newsletter/birds%20of%20Pench%20Tiger%20R.pdf}}</ref> }} {{refbegin}} {{refend}}
==External links== * {{BirdLife|62026537|Gelochelidon macrotarsa}} * {{IUCN_Map|62026537/132671766|Gelochelidon macrotarsa}}
{{Taxonbar|from=Q55111914}}
Australian tern Category:Birds of Australia Australian tern Australian tern