Black capped Chickadee

The Black-capped Chickadee, Parus atricapillus or Poecile atricapilla, is a small songbird, a passerine bird in the tit family Paridae.Adults have a black cap and bib by means of white sides to the face. Their underparts are white with rusty brown on the flanks; their back is grey. They have a short dark bill, short wings and a long tail.Their breeding habitat is mixed or deciduous woods in Canada, Alaska and the northern United States. They nest in a hole in a tree; the pair excavates the nest, using a natural cavity or sometimes an old woodpecker nest. They may interbreed with Carolina Chickadees or Mountain Chickadees where their ranges overlap.They are permanent residents, but sometimes move south inside their range in winter. On cold winter nights, these birds reduce their body temperature to conserve energy.
The call is the familiar chick-a-dee-dee-dee which gave this bird its name. Recent study of the call shows that the number of dees indicates the level of threat from nearby predators. This is the provincial bird of New Brunswick and the state bird of Maine and Massachusetts.Taxonomic note: Most authorities retain Poecile as a subgenus within a broader view of the genus Parus, but the American Ornithologists' Union treats Poecile as a distinct genus.