Chimney Swifts are very small birds with slender bodies
They have round heads, short necks, and short, tapered tails.
They are dark gray-brown all over, slightly paler on the throat.
Chimney Swifts fly rapidly with nearly constant wing beats, and often twist from side to side and bank erratically.
They often give a high, chattering call while they fly.
Chimney Swifts nest in chimneys and on other vertical surfaces in dim, enclosed areas, including air vents, wells, hollow trees, and caves. They forage over urban and suburban areas, rivers, lakes, forests, and fields.