Purple Martins are a native bird that nests in massive colonies, but only in human-made homes.  They're an effective way to control insect populations and have been a favorite species of birdwatchers since precolonial times.  To learn more about their behavior and how to be a good purple martin landlord, we talked to naturalist Mary Schmidt at Lichterman Nature Center.Music and Sound production by Sully Allen, Boon, and Luke Ramsey.