Unmistakable if seen well. Corvoid-like at a distance, and may be mistaken for Jay if no plumage characters are visible. Tail is however quite a bit shorter, and wings slightly longer. Flight-feathers dark, contrasting with turquois coverts, both below and above. Underparts especially striking in flight, being pale blue (sometimes seemingly white) all over, except dark flight-feathers and base of tail. Bill heavy. Immature duller than adults with faint streaked breast and slightly rufous coverts. Wing-beats deep and regular. Flies mostly in a straight line. Migrating birds move in characteristic procession-like formations.

Various dry rasping, sometimes mewing, sounds and short clicks: "ahrahrahrahrahrahrahr" or pulse of clicks: "trrrtrrrrtrr". Also a clearer raptor- or jay-like descending "piiuu".

Display calls:

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:Jarek Matusiak, Licence,Link.