Appearance:

Very large tern, with deep, dagger-like, blood-red bill with dark tip. Large, black cap reaching well below the eyes. Grey upperparts and white underparts. Rather short tail. Outer primaries distinctly darker than the rest of upperwing, and outer underwing almost black. Unmistakable from the size alone, and leaves a gull-like impression, lacking the elegance of smaller terns. Immatures with paler bill and white forehead (as in adult winter), and markedly speckled back. Hovers and dives. Often rests on the surface, feeding like a gull.

Sound:

Easily recognized by its very harsh calls. Sometimes likened to the sound of a plate of steel being dragged across a concrete floor. Similar in harshness to Grey Heron, but more drawn, with an accented middle; "Kraaeeet", or with a double syllable start "ka-ha-kraaaeet". Immature birds begs with a penetrating, sharp whistle.

Contact call:

Distribution:

Wikipedia: map (se also Xeno-canto below)

Ecology:

Birdlife ecology

Links:

Observation.org Latest observations

Video IBC

Image search Flickr NB! May give other species

Sound search at Xeno-canto

CC

CC-photo:lgooch, Licence,Link.

CC-photo:Muchaxo, Licence,Link.

CC-photo:ajmatthehiddenhouse, Licence,Link.

Appearance:

Differs from Arctic Tern in longer head, and more orangy red, rather than deep red, bill. Tip of bill usually black. Legs longer, but tail streamers shorter than AT. Underparts of primaries with diffusely bordered dark trailing edge (sharply bordered in Arctic Tern). Upper side of primaries with dark wedge (less apparent in winter). Secondaries opaque. Crest more apparent than in Arctic Tern and underside whiter. Juveniles with buff back.

Sound:

Similar to Arctic Tern but deeper. Lacks latter's high pitched "tip-tip-tip" call, and the drawn out "kree-aaahh" call falls more distinctly in pitch.

Call:

Distribution:

Wikipedia: map (se also Xeno-canto below)

Ecology:

Birdlife ecology

Links:

Observation.org Latest observations

Video IBC

Image search Flickr NB! May give other species

Sound search at Xeno-canto

Featherbase

CC

CC-sound:Eetu Paljakka, Licence,Link.