Effigy Mounds National Monument - Wetlands, Marshes and Swamps (U.S. National Park Service)

Buffalo pond wetland

The backwaters of the Mississippi River consist of sloughs, lakes, ponds and adjacent wetlands. These areas have been altered by sedimentation that is rapidly filling in lakes and ponds and blocking channels. The backwaters are home of many interesting plants and animals. The majestic bald eagle nest on islands and feed on fish they pull from the river with their powerful talons. Hundreds of bald eagles winter along the Upper Mississippi River in the vicinity of Effigy Mounds National Monument. The Upper Mississippi Wildlife and Fish Refuge, stretching from Wabasha, Minnesota to Rock Island, Illinois, a distance of 260 miles, protects habitat for the bald eagle and many other riverine species of the river. In the coldest winters, when open water is scarce, eagles move further down the river. Tree nesting areas called rookeries contain great blue heron, great egrets and double crested cormorants. The rookeries are noisy places in spring with young fledglings being fed by their parents. Painted, map, and false map turtles are often sighted sunning on logs close to the water. Beaver, river otter, muskrat and mink occupy the quiet water sloughs and river edges. A wide variety of hardwood trees provide habitat for animals of the floodplain forest. Swamp white oak produce large acorns eaten by many animals including wild turkey, white tailed deer and wood ducks. Red bellied, redheaded, downy, hairy, and the large pileated woodpecker make their homes in dead trees within the floodplain forest. The Yellow River wetlands, within Effigy Mounds National Monument, are made up of the slow moving river, and the adjacent floodplain, several small shallow ponds and a tributary stream, Dousman Creek. The wetlands contain habitat for many resident and migratory birds. In spring and fall, wood ducks, mallards, Canada geese and other waterfowl can be found feeding and resting in the quiet waters of Founder’s Pond. From the Founder’s Pond overlook, visitors can often see bald eagles and an occasional osprey during migration. Many types of amphibians utilize the wetlands as well. Spring peepers, western chorus frogs, green frogs, leopard frogs, pickerel frogs and bullfrogs and American toads can be found here. In early spring the chorus of frogs rises from the ponds and continues through early summer as various species begin their ancient courtship ritual. In summer, the trill of the common gray treefrog can be heard from the trees and shrubs near the water.