More than 3,600 species of plants, fish, and wildlife live in the Chesapeake Bay region. The Sassafras River and Turner's Creek, tributaries of the bay, provide food and shelter for great blue herons, osprey, otters, beaver, largemouth bass, and other wildlife. Aquatic plants in local rivers and creeks shelter crabs and young fish and serve as food for migrating waterfowl. Boaters are urged to avoid disturbing submerged aquatic vegetation beds, because propellers and impellers can uproot vegetation.