Whiskered Tern (Chlidonias hybrida)
Glaucous Gull (Larus hyperboreus)
Largest marsh tern. Liable to confusion with Sterna terns due to black cap, in addition to other marsh terns. All marsh terns (Chlidonias) differs from Sterna by lack of tail streamers, short tail with shallow fork, shorter wings and stiffer flight. Marsh terns don't plunge-dive for food but picks from surface (though Whiskered Tern may belly-plunge), mostly in fresh water. Adult Whiskered Tern easily told from other marsh terns by distinct black cap contrasting to white cheeks and throat. Underwing pale with diffuse dark trailing edge. Belly distinctly darker than Common- and Arctic Tern, but beware of variation in both species. Bill dark blood red. Adult winter: Very pale with no distinct markings except for ill-defined black mask stretching from eye to eye across nape. Forehead white and with crown white speckles. Bill black. Immature: Yellowish brown saddle with coarse dark pattern, though these are moulted in early autumn. Usually lacks dark carpal bar and cap ill-defined. Whiskered Tern generally stockier built than other marsh terns. Both immatures and adult winter show grey rump (different from Common, Arctic and White-Winged), and bill is dagger-shaped (most apparent in males).
Sound:Contact call freely used and fairly distinct: An extremely hoarse, and rasping "krreek" in various moods. Timbre comparable to Corncrake. Sometimes uttered in stuttering series "kr-kr-kr-kr-kr".
Contact call:
Distribution:
Xeno-canto: map
Ecology:Birdlife ecology
Links:
Observation.org Latest observations
Image search Flickr NB! May give other species
CCCC-sound:Patrik Åberg, Licence,Link.
CC-photo:Jurrien van Deijk, Licence,Link.
CC-photo:Geert Moris, Licence,Link.
All white wingtips like Iceland Gull. The following characters applies to all ages: Told apart from Iceland Gull by angular head profile, proportionally shorter wings and long, heavy bill. Bill longer than half the length of head, and shows prominent hook. Primaries extends just about past tail in sitting birds, and the whole rear of the bird seem heavier. Eye smaller than in Iceland Gull, with a stern expression. Comparison with nearby Herring Gulls fruitful. Iceland Gull often smaller than Herring Gull, and less heavy, while Glaucous Gull usually larger. Impression reinforced by Iceland's agile maneuvering.
Sound:Like Herring Gull.
Call:
Distribution:
Wikipedia: map (se also Xeno-canto below)
Ecology:Birdlife ecology
Links:
Observation.org Latest observations
Image search Flickr NB! May give other species
CC