Chautauqua National Wildlife Refuge is a wetland refuge along the Illinois River northeast of Havana, Illinois, managed as part of the Illinois River National Wildlife and Fish Refuges. Covering 4,388 acres plus the detached 1,079-acre Cameron/Billsbach Unit near Henry, it occupies land once enclosed for farming by the Chautauqua Drainage and Levee District. That agricultural polder failed in the 1920s, and the Illinois River reclaimed the tract as broad, shallow Chautauqua Lake. Acquired by the federal government in 1936, the area has since been managed for wildlife habitat and flood control while facing runoff, siltation, and invasive species. A nesting pair of bald eagles was observed there in winter 2005–06.