Chouteau Island is actually a 5,500 acre three-island portion which includes Chouteau Island (3,200 acres), Mosenthein Island (1,000 acres), & Gabaret Island (1,300 acres). All combined go by the name Chouteau Island. The island is closed from dusk to dawn & the Old Chain of Rocks Bridge opens at 9am. Due to its location the island is great for American Bald Eagle spotting in certain times of the year. Some events are also hosted on the island but mainly on the Old Chain of Rocks Bridge.