A chimney swift is a small, migratory bird native to the eastern half of the United States and South America. Chimney Swifts are protected by the federal government under the Migratory Bird Treaty Act and cannot be removed from any nesting spot. If you think a chimney swift is nesting in your chimney, call a wildlife removal service to confirm your suspicions, but if you indeed do have a family of swifts in your chimney, you will have to wait until the babies leave in order to do anything about it. There are preventative measures you can take though. Having a weather cap installed before nesting season begins in May can help prevent animals, water, snow, and debris from entering your chimney.