Resembles a big, black Curlew, but can only be confused with Bald Ibis. Differs from this by longer, slender neck, rounded and feathered head, long legs (trailing in flight) and heavier bill. Bare parts greyish, not red. Adults with glossy green wings. Immatures and birds in winter plumage with white-speckled head and neck. Head and legs droops slightly below horizontal plane in flight, leaving a "hunched" impression. Wing beats faster than herons of same size. May glide longer distances, but does not soar like Bald Ibis. Flight formation loose, diagonal or in single file with undulating movements.

Generally silent away from breeding ground. Dry, crow-like "garr garr", may be heard occasionally in flight. At breeding ground various guttural grunts, and piping, hissing sounds.

Flightcall:

Wikipedia: map (se also Xeno-canto below)

Birdlife ecology

Observation.org Latest observations

Video IBC

Image search Flickr NB! May give other species

Sound search at Xeno-canto

Featherbase

CC-sound:Stanislas Wroza, Licence,Link.