Inquire about a company’s policy regarding Chimney Swifts. Many companies actively promote the conservation of Chimney Swifts. Any company advertising a “bird removal” service should be avoided, as this is a violation of state and federal laws protecting Chimney Swifts and other migratory birds. The best time to have your chimney cleaned is in late March, after the winter heating season and before swifts have returned to their summer range in North America.