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Tufted duck – Aythya fuligula

Tufted duck – Aythya fuligula
is a small diving duck. The adult male is all black except for white flanks and a blue-grey bill. It has an obvious head tuft that gives the species its name. The adult female is brown with paler flanks, and is more easily confused with other diving ducks. In particular, some have white around the bill base which resembles the scaup species, although the white is never as extensive as in those ducks.

It sounds like this
Recording by Terje Kolaas from Xeno canto