Description wikipedia

The azure tit (Cyanistes cyanus) is a passerine bird in the tit family Paridae. It is a widespread and common resident breeder throughout Russia, Central Asia, northwest China, Manchuria, and Pakistan. It is found in temperate and subarctic deciduous or mixed woodlands, scrub, and marshes. It is a resident species, and most birds do not migrate. It nests in tree holes, laying approximately 10 eggs. The bird is a close sitter, displaying defensive behaviors such as hissing and biting when disturbed. Its diet primarily consists of insects, seeds, small invertebrates, bug larvae, and eggs. This 12–13 cm (4.7–5.1 in) bird is unmistakable. Its head, tail corners, wing bars, and underparts are white, while the upperparts are blue. It has a distinctive dark line running through its eye. This bird is the eastern counterpart of the common Eurasian blue tit. It will hybridise with that species, but the offspring usually show a blue crown, rather than the white of azure tit. The calls are similar to blue tit, calling dee, dee, dee or a scolding churr. The song is a tsi-tsi-tshurr-tsi-tsi-tshurr, which has been described as intermediate between blue tit and crested tit. There are some records of the species in other parts of Europe, including in Finland, Sweden, Poland and Austria.