Range. - Whole of North America, wintering in the United States and southward; breeds throughout its range, but most abundantly in northern United States and northward. This is one of the smallest of the hawks and in the adult plumage is a beautiful species, being barred below with light brown, and having a bluish slate back. It is a very spirited and daring bird and is one of the most destructive to small birds and young chickens. Its nest is a rude and sometimes very frail platform of twigs and leaves placed against the trunk of the tree at any height, but averaging, perhaps, fifteen feet. The eggs are bluish white, beautifully blotched and spotted with shades of brown.