This spring and earlier this summer, three swifts were chitter-chattering high in the sky whenever I went outside. Once they arrive back in North Carolina from their South American wintering grounds in April and May, pairs of swifts choose a chimney in which to nest, often accompanied by an unmated helper. The chosen chimney will accommodate only one set of nesting swifts, although it may also be home to roosting unmated birds. As the breeding season tapers off in August, all adults and young begin to congregate in roosting chimneys to spend the night. In the fall, when the swifts gather in large numbers to prepare for migration, these congregations can become very large – in some cases, in the thousands. This is when spectators are treated to an incredible sight, the swirling of hundreds of swifts around their roost chimney. Local Audubon chapters and other groups organize “Swift Night Out” or “Chimney Swift Watch” viewing events to behold the magic. In my neighborhood, about 75 birds circle around my local middle school’s old brick chimney. As the sky darkens, the swifts, one by one and then in small groups, leave their funneling neighbors to drop effortlessly into the chimney top, until only the stars remain in the sky.