Night Heron (Nycticorax nycticorax)
White-winged Tern (Chlidonias leucopterus)
Small, crepuscular, stocky heron with short legs. Adults unmistakable with black cap, black back, grey wings and white underparts. Immature less distinct, and may be confused with immature Squacco Heron, Little Bittern or Bittern. Differs from all these in distinct white spots covering both wings and back. Belly and breast are more widely covered in coarse streaking, not just the sides or upper chest. Legs just barely protrudes behind tail in flight.
Sound:Most commonly hear call is a nasal, soft croaking "roack", like cross between Raven and frog.
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
CCBreeding adult easily identified by white tail/rump combined with jet black under wing coverts and silvery upper wing. Immature with brownish back contrasting with pale, silvery upper wings and pale rump. Broad white collar, and lacks dark breast patch of immature Black Tern. Adult winter most liable to confusion with other terns, but upperparts much paler than Black Tern. Contrasting dark outer primaries and secondaries to rest of wing. Often retains some black under coverts even in winter which is diagnostic if seen. Slightly more compact than Black Tern and often recalls Little gull in shape. Bill noticeably shorter and thinner than in Whiskered Tern.
Sound:Mostly silent away from breeding ground. Most diagnostic call a dry, rolling "krrrrrr-ta-ta" where the rolling is followed by one or two accentuated syllables, or just simply "krrrrrr". Used in excitement.
Call:
Distribution:
Xeno-canto: map
Ecology:Birdlife ecology
Links:
Observation.org Latest observations
Image search Flickr NB! May give other species
CCCC-sound:Marco Dragonetti, Licence,Link.