Chimney Swifts, as their name suggests, are known to nest and roost in chimneys and other hollow manmade structures. These small birds, with a unique cigar shape, are migratory insectivores, returning each spring to breed in Canada and the United States, and flying down to South America in the fall.
According to the COSEWIC Assessment and Status Report on the Chimney Swift, the population has decreased by 95 per cent since 1968, qualifying the bird as a Species at Risk. The cause of the decline is thought to be brought about by a combination of changing weather patterns, food scarcity and a reduction in roosting habitat.
Unpaired birds and juveniles roost communally in larger structures with the number of individuals growing during the course of the season as fledglings and parents join the group. A single stack can provide a home to thousands of birds. Between the Maritimes, Quebec and Ontario, 750 roosts have been identified, one of which is at the Nuclear Power Demonstration (NPD) reactor in Rolphton.