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Tern

2007 Schools Wikipedia Selection. Related subjects: Birds

                  iTerns
   Arctic Tern
   Arctic Tern
         Scientific classification

   Kingdom:  Animalia
   Phylum:   Chordata
   Class:    Aves
   Order:    Charadriiformes
   Suborder: Lari
   Family:   Sternidae
             Bonaparte, 1838

                                   Genera

     * Anous
     * Procelsterna
     * Gygis
     * Onychoprion
     * Sternula
     * Phaetusa
     * Hydroprogne
     * Gelochelidon
     * Larosterna
     * Chlidonias
     * Thalasseus
     * Sterna

   Terns are seabirds in the family Sternidae, previously considered a
   subfamily (Sterninae) of the gull family Laridae (van Tuinen et al.,
   2004). They form a lineage with the gulls and skimmers which in turn is
   related to skuas and auks. Terns have a worldwide distribution.

   Most terns were formerly treated as belonging into one large genus
   Sterna, with the other genera being small, but analysis of DNA
   sequences supports the splitting of Sterna into several smaller genera
   (see list, below) (del Hoyo et al., 1996; Bridge et al. 2005; Collinson
   2006).

   Many terns breeding in temperate zones are long-distance migrants, and
   the Arctic Tern probably sees more daylight than any other creature,
   since it migrates from its northern breeding grounds to Antarctic
   waters. One Arctic Tern, ringed as a chick (not yet able to fly) on the
   Farne Islands off the Northumberland coast in eastern Britain in summer
   1982, reached Melbourne, Australia in October 1982, a sea journey of
   over 22,000 km (14,000 miles) in just three months from fledging - an
   average of over 240 km per day, and one of the longest journeys ever
   recorded for a bird.

   They are in general medium to large birds, typically with grey or white
   plumage, often with black markings on the head. They have longish bills
   and webbed feet. They are lighter bodied and more streamlined than
   gulls, and look elegant in flight with long tails and long narrow
   wings. Terns in the genus Sterna have deeply forked tails, those in
   Chlidonias and Larosterna shallowly forked tails, while the noddies
   (genera Anous, Procelsterna, Gygis) have unusual 'notched wedge' shaped
   tails, the longest tail feathers being the middle-outer, not the
   central nor the outermost.

A flock of Royal Terns in flight in Florida, USA.

                                                 Common Tern by the River Thames

   Most terns (Sterna and the noddies) hunt fish by diving, often hovering
   first, but the marsh terns (Chlidonias) pick insects of the surface of
   fresh water. Terns only glide infrequently; a few species, notably
   Sooty Tern, will soar high above the sea. Apart from bathing, they only
   rarely swim, despite having webbed feet.

   Terns are generally long-lived birds, with several species now known to
   live in excess of 25-30 years.

Classification and species list

   A recent study (Thomas et al., 2004) of part of the cyt b gene sequence
   found a closer relationship between terns and the Thinocori, some
   species of aberrant waders. These results are in disagreement with
   other molecular and morphological studies (see Paton & Baker, 2006) and
   are best interpreted to prove an extraordinary amount of molecular
   convergent evolution between the terns and these waders, or as
   retention of an ancient genotype.

   According the mtDNA studies and review by Bridge et al (2005), the
   genera and species of terns are as follows:
     * Genera Anous, Procelsterna, Gygis - noddies. A tropical group,
       characterised by the notch-wedge shaped (not forked) tail; coastal
       and pelagic oceanic.
          + Brown Noddy Anous stolidus
          + Black Noddy Anous minutus
          + Lesser Noddy Anous tenuirostris
          + Blue Noddy Procelsterna cerulea
          + Grey Noddy Procelsterna albivitta
          + White Tern Gygis alba
          + Little White Tern Gygis microrhyncha

     * Genus Onychoprion - "brown-backed" terns
          + Grey-backed Tern Onychoprion lunata
          + Bridled Tern Onychoprion anaethetus
          + Sooty Tern Onychoprion fuscata
          + Aleutian Tern Onychoprion aleutica

     * Genus Sternula - little white terns
          + Fairy Tern Sternula nereis
          + Damara Tern Sternula balaenarum
          + Little Tern Sternula albifrons
          + Saunders's Tern Sternula saundersi (formerly considered a
            subspecies of Little Tern)
          + Least Tern Sternula antillarum (formerly considered a
            subspecies of Little Tern)
          + Yellow-billed Tern Sternula superciliaris
          + Peruvian Tern Sternula lorata

     * Genus Phaetusa - Large-billed Tern
          + Large-billed Tern Phaetusa simplex

     * Genus Hydroprogne - Caspian Tern
          + Caspian Tern Hydroprogne caspia

     * Genus Gelochelidon - Gull-billed Tern
          + Gull-billed Tern Gelochelidon nilotica

     * Genus Larosterna - Inca Tern
          + Inca Tern Larosterna inca

     * Genus Chlidonias - marsh terns
          + Black Tern Chlidonias niger
          + White-winged Tern or White-winged Black Tern Chlidonias
            leucopterus
          + Whiskered Tern Chlidonias hybridus
          + Black-fronted Tern Chlidonias albostriatus (ex-Sterna
            albostriata)

     * Genus Thalasseus - crested terns
          + Lesser Crested Tern Thalasseus bengalensis
          + Royal Tern Thalasseus maximus
          + Greater Crested Tern or Swift Tern, Thalasseus bergii
          + Chinese Crested Tern Thalasseus bernsteini
          + Elegant Tern Thalasseus elegans
          + Sandwich Tern Thalasseus sandvicensis

     * Genus Sterna - large white terns
          + Forster's Tern Sterna forsteri
          + Trudeau's Tern Sterna trudeaui
          + Common Tern Sterna hirundo
          + Roseate Tern Sterna dougallii
          + White-fronted Tern Sterna striata
          + Black-naped Tern Sterna sumatrana
          + South American Tern Sterna hirundinacea
          + Antarctic Tern Sterna vittata
          + Kerguelen Tern Sterna virgata
          + Arctic Tern Sterna paradisaea
          + River Tern Sterna aurantia
          + Black-bellied Tern Sterna acuticauda (possibly Chlidonias)
          + White-cheeked Tern Sterna repressa (possibly Chlidonias)

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