The Falkner Island Light was constructed in 1802 and commissioned by President Thomas Jefferson. The light is the second oldest in Connecticut and is listed on the National Register of Historic Places. The lighthouse was automated in 1978, and continues to operate as a navigational aid to the nearby Intracoastal Waterway. The island is part of the Stewart B. McKinney National Wildlife Refuge and has the fifth-largest colony of nesting roseate terns in the northeastern United States. Much of the island's land mass has been lost to erosion, down to about from its original . The United States Army Corps of Engineers reinforced the eastern boundary to slow the advancing deterioration.