Combination of striking black and white head and yellow underparts makes it rather unmistakable. Back greenish, tail and wings bluish. Outer tail feathers white. Sexes alike except for wider black belly-stripe in males. Biggest tit.
Sound:Song highly variable, but usually consisting of two to three notes repeated in a motif. Same birds have many different motifs but generally repeat them many times before switching. Identified by its timbre and often metallic resonant quality, more than by actual phrasing (which is very variable). Often includes buzzing sounds in song. Generally more full-bodied and resonant calls than blue tit, and not so high-pitched. Characteristic Chaffinch-like "tink tink tink" often uttered by male.
Song:
Distribution:
Wikipedia: map (se also Xeno-canto below)
Ecology:Birdlife ecology
Links:Observation.org Latest observations
Image search Flickr NB! May give other species
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