Cliff Swallow

Cliff Swallow, common name for a group of birds belonging to the large swallow genus and especially for a species found throughout most of North America. This species originally nested in dense colonies on rocky cliffs, and still does so in some areas of the west, but as human settlements were established it began building its flask-shaped nests—composed of mud pellets—on the outsides of farm buildings and other structures. The cliff swallow has a short, square tail; blue-black crown, back, wings, and tail; a pale grey or buff forehead; and a conspicuous buff or reddish-brown patch on the rump. It winters in South America.

Scientific classification: Cliff swallows belong to the genus Hirundo of the family Hirundinidae, order Passeriformes. The common species of North America is classified as Hirundo pyrrhonota.