Big and white waterfowl with orange bill and black knob at base of bill. Juveniles more greyish and differs from juvenile Whoopers by all grey bill and black lores. Neck usually held more S-shaped than other swans when swimming. Long tail prominent when upending.

Silent compared to other swans. A repertoire of snorting, grunting and hissing sound when interacting. No far carrying sounds. Wings produce prominent singing sound which may function as a flight contact-call.

Social sounds:

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:Peter Boesman, Licence,Link.