The white-winged tern, or white-winged black tern (Chlidonias leucopterus or Chlidonias
leucoptera), is a species of bird in the familySternidae,
the terns. It is a small species generally found in or near bodies of fresh
water across much of the world, including Europe, Africa, Asia, and Australia.
The genus name is from Ancient Greek khelidonios,
"swallow-like", from khelidon,
"swallow". The specificleptopterus is also Greek from leptos, "slender",
and pteros,
"feathered", itself from pteron,
"wing".
The
name 'white-winged tern' is the standard in most English-speaking countries; in
the United Kingdom, this name is also the one used
by the formal ornithological recording authorities, but the older alternative
'white-winged black tern' is still frequent in popular use.
Adult birds in
summer have short red legs and a short black bill (small and stubby, meausuring
22–25 mm from the feathers, decidedly shorter than the head), a black neck
(often with a pale gray back) and belly, very dark grey back, with a white rump
and light grey (almost white) tail, which often looks 'square' in juveniles.
The face is tinged yellowish. The wings, as the name implies, are mainly white.
The inner wing is grayish with brown-tipped coverts. In non-breeding plumage,
most of the black is replaced by white or pale grey, though a few blackish
feathers may be retained, admixed with white underparts. A good deal of black
shows in the underwing-coverts. The head is black, with a white forehead. The
crown is blackish-brown, flecked with white, and the hindcrown is blackish with
a certain amount of white flecking. These white markings are pronounced in the
winter adult. There is a dark triangular patch forward of the eye. The collar
is fairly broad and white.
Like the other
"marsh" terns (Chlidonias), and unlike the "white" (Sterna) terns,
these birds do not dive for fish, but fly slowly over the water to surface-pick
items on the surface and catch insects in flight. They mainly eat insects and
small fish.
[info:wikipedia]
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