Bonelli's Eagle (Aquila fasciata)
Black Tern (Chlidonias niger)
Medium sized eagle with long wings and tail. Pale base of outermost primaries in all plumages (lacking in Booted Eagle). Adults easily identified by dark greater coverts forming mid wing band on underwing, in combination with pale body and pale lesser coverts (variable). Tail clear cut (but not as pointed corners as in Booted Eagle) with broad terminal band. Back with diagnostic white patch (variable). Immature told from dark and medium morph of Booted Eagle by pale base of outer primaries, narrowly and evenly barred tail (bands reaching outer edge). The species show less fingered wings than many congeners, and long tail combined with small head may recall Honey Buzzard. Characteristic gliding profile with projected carpal joints and straight trailing edge of wing. Slight S-shape to trailing edge of wing when soaring. Flight agile and falcon-like.
Sound:Not very vocal, but may call at breeding ground. Commonest call a sharp, gull-like "kleeee", beginning with marked register-break followed by drawn-out note with fairly stable pitch, unlike most congeners.
Call:
Distribution:
Xeno-canto: map
Ecology:Birdlife ecology
Links:
Observation.org Latest observations
Image search Flickr NB! May give other species
CCCC-photo:Jorrit Vlot, Licence,Link.
CC-photo:Paul Cools, Licence,Link.
CC-photo:ruwan aluvihare, Licence,Link.
Unmistakable 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