Common resident, in places rare winter visitor. Inhabits the coniferous, mixed and deciduous forests on plains and in mountains at altitudes to 1900 m. On dispersal occurs in deciduous forests in Ural valley. Pairs are formed in March – mid April. Nest is located in tree hole (larch, birch) at height 2-20 m above the ground; nest is built from bark, plant bast and leaves. If the hole entrance is too large, then birds plaster its by clay leaving a hole diameter of 25-35 mm. Only female constructs nest, male escorts her. Clutch of 5-10, usually 6-8 eggs is laid in early May – early June. Female incubates clutch about two weeks, both parents feed juveniles which fledge at age 21-24 days old, in mid-June to mid-July. Broods stay together until mid-August. Very rarely occurs on dispersal in Ural valley in October.