Gamayun is a symbol of wisdom and knowledge, a talking bird who foretells the future and tells fortunes. Its name is derived from the Russian word “gam” or “kam”, meaning “noise”, hence are the words “kamlat” (i.e. to perform shamanistic rituals) and “shaman”. In the Belorussian language the word “gamanits” means “to speak, to talk”.
Like the Sirin and the Alkonost, the Gamayun is normally depicted as a large bird with a woman's head. In Old Russian tradition Gamayun Bird served to pagan gods, namely Veles, Kryshen, Kolyada and Dazhbog, and she was the one who sing the Book of the Vedas.
In his esoteric Christian-Buddhist cosmography Roza Mira, Daniil Andreev maintains that Sirins, Alkonosts, and Gamayuns are transformed into Archangels in Paradise.
image source : http://epika.org/house-of-mythology/27-gamayun