m |
|||
Line 18: | Line 18: | ||
==Taxonomy== | ==Taxonomy== | ||
This is a [[Dictionary_M-O#M|monotypic]] species<sup>[[#References|[3]]]</sup>. | This is a [[Dictionary_M-O#M|monotypic]] species<sup>[[#References|[3]]]</sup>. | ||
− | [[Image:Arctictern.jpg|thumb|350px|right|Immature Arctic Tern <br />Photo by the late | + | [[Image:Arctictern.jpg|thumb|350px|right|Immature Arctic Tern <br />Photo by the late '''[http://www.birdforum.net/gallery/showgallery.php?cat=500&ppuser=35827 Jim Wood]'''<br />Location: [[Shetland Islands]]]] |
==Habitat== | ==Habitat== |
Revision as of 06:22, 28 July 2015
- Sterna paradisaea
Identification
Length 33–39 cm, mass 76-116 g.
Breeding adult: Black forehead, nape and crown and white cheeks; the mantle, back and upper wings are grey and the collar, rump and underwing are white. The deeply forked tail is white with grey outer webs. The long bill, legs and feet are red.
Non-breeding adult and immature: Forehead white, crown streaked black and white, nape black. The bill is black and the legs and feet dark red to blackish.
Similar Species
Common and Arctic Terns are a species pair easily confused.
On the ground the short legs of Arctic terns give them a somewhat huddled look whilst the tail feathers in summer birds extends well beyond the folded wings. Common stand taller and the tail feathers don't extend past the primaries.
On flying birds the wing of Arctic when seen against the light is really quite translucent whereas in Common only the inner primaries are translucent. Common Terns have a black wedge or notch effect on the upper outer 5/6 primaries which is absent in Arctic and the trailing black edge of the primaries is narrower and neater in Arctic.
I find the easiest way to separate them in Summer is by the fact that Arctics have a very buoyant bouncy flight and are more compact in the head and neck coupled with the long tail giving the impression that the wings are well-forward on the body whereas Common Terns seem to have their wings more to the centre of the bird. The real clincher however is the beak - Common Tern has a fairly long somewhat decurved orange-red beak with a clear black tip whilst Arctic terns have a shorter solid blood-red beak (and are more likely to draw blood when you invade the nesting colony!!)
Written by Steve G
On real close ups, look for the color at the crescent under the eye: black in Arctic Tern, white in Common, creating different impressions on completeness of the mask.
Distribution
Breeds in arctic and sub-arctic Europe, Asia, and North America. Migrates to the Antarctic for another summer. Accidental in Kansas.
Taxonomy
This is a monotypic species[3].
Habitat
Oceans. Nests on islands in the Arctic.
Behaviour
Diet
The diet includes fish and small marine invertebrates.
Breeding
The nest is a depression in the ground and 1-3 mottled eggs are laid. Both parents incubate the eggs for 27 days; the young fledge after 21–24 days.
Vocalisation
<flashmp3>Sterna paradisaea (song).mp3</flashmp3>
Listen in an external program
References
- Hockey, PAR, WRJ Dean, and PG Ryan, eds. 2005. Roberts' Birds of Southern Africa. 7th ed. Cape Town: John Voelcker Bird Book Fund. ISBN 978-0620340533
- Wikipedia
- Clements, JF. 2011. The Clements Checklist of Birds of the World. 6th ed., with updates to August 2011. Ithaca: Cornell Univ. Press. ISBN 978-0801445019. Spreadsheet available at http://www.birds.cornell.edu/clementschecklist/downloadable-clements-checklist
- Birdforum thread discussing separation of Common vs Arctic Terns and mentioning eye crescent in post #12
Recommended Citation
- BirdForum Opus contributors. (2024) Arctic Tern. In: BirdForum, the forum for wild birds and birding. Retrieved 4 May 2024 from https://www.birdforum.net/opus/Arctic_Tern
External Links