Usually recognizable by size alone. Distinctly smaller than any congener. Pale wing-panel formed by inner coverts is striking in all plumages, especially in flight. Male with contrasting black and white/buff plumage. Female with dark, but pale fringed back and streaked throat. Immature with streaked, bittern-like plumage, and wing-panel is brown-spotted. Skulky behaviour, and most active at dusk or after dark. Mostly seen in flight when crossing open water. Flight action rapid and clipping, and landing is preceded by short glide.

Mostly silent except in breeding season. Song is a series of short, deep, frog-like "gorrk", repeated every 2 seconds. Tone is muffled and hollow, but far-carrying. Flight-call a sharp "ki-ke-ke" or a nasal "ke".

Song:

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

Sound recording:Creative Commons,www.xeno-canto.org,Jarek Matusiak,http://creativecommons.org/licenses/by-nc-sa/4.0/