Roller (Coracias garrulus)
Black Tern (Chlidonias niger)
Unmistakable if seen well. Corvoid-like at a distance, and may be mistaken for Jay if no plumage characters are visible. Tail is however quite a bit shorter, and wings slightly longer. Flight-feathers dark, contrasting with turquois coverts, both below and above. Underparts especially striking in flight, being pale blue (sometimes seemingly white) all over, except dark flight-feathers and base of tail. Bill heavy. Immature duller than adults with faint streaked breast and slightly rufous coverts. Wing-beats deep and regular. Flies mostly in a straight line. Migrating birds move in characteristic procession-like formations.
Sound:Various dry rasping, sometimes mewing, sounds and short clicks: "ahrahrahrahrahrahrahr" or pulse of clicks: "trrrtrrrrtrr". Also a clearer raptor- or jay-like descending "piiuu".
Display calls:
Distribution:
Wikipedia: map (se also Xeno-canto below)
Ecology:Birdlife ecology
Links:
Observation.org Latest observations
Image search Flickr NB! May give other species
CCUnmistakable in breeding plumage, but otherwise easily confused with other marsh terns. Breeding plumage with black head and belly, but pale underwing and grey rump. When in immature and winter plumage it differs from Common and Arctic tern by smaller size and short, moderately forked tail, and from other marsh terns by slimmer body and wings (compared to White-winged tern), and relatively long, thin bill. Both immature and adult winter show dark front edge of wing, and characteristic dark shoulder patch at wing base. Back is dark in immature birds. Grey rump in all plumages. Flight usually different from Sterna-terns, with erratic dives for no apparent reason, and "aimless" change of direction. Note that when foraging over saltwater, flight becomes more Sterna-like.
Sound:Moderately vocal. Flight call a more or less clear "kleck, or a disyllabic "klee-ake" with accented first syllable. Sometimes slightly rolling "klirr-eke", but never as much as in White-winged Tern. Also a slightly harsher "kreek", but not as raspy as in Whiskered Tern.
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
CC