Pomarine Jaeger (Stercorarius pomarinus)
Whiskered Tern (Chlidonias hybrida)
Pale and dark morphs. Often difficult to distinguish from Arctic Skua. Adults with broad, spoon-shaped streamers. These are moulted twice a year, so adults lacking these are not uncommon. The dark cap reaches around the bill base and down to the chin. Breast band in pale morph is generally broader and more pronounced than in Arctic Skua, but in some males it is lacking altogether. Leaves an overall more robust and powerful impression than Arctic. Wings are broader than the distance from trailing wing-edge to tip of tail (streamers excluded), while the hand seems shorter. The light patches at the base of the primaries are more obvious, and many young birds shows a characteristic double patch, formed by additional white base of greater primary coverts (like Lesser Spotted Eagle). Rump and vent of juveniles usually boldly barred, in contrast to unbarred back and belly (visible even in dark morph). Streamers never pointed (in any plumage). Flight pattern straighter, and more determined than in Arctic Skua.
Sound:Short "kea" or "ke", and various mewing calls, usually deeper pitched than Arctic Skua. Also a characteristic, laughing and vibrating "kayayayayaya", heard mostly on breeding ground.
Alarm/flight 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
CCCC-photo:loarie, Licence,Link.
CC-photo:jerryoldenettel, Licence,Link.
Sounds:CC. http://www.xeno-canto.org .Recorded by Andrew Spencer.
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.