Large birds such as sandhill cranes feed on the abundant crustaceans, while owls and hawks prey on small mammals and birds. They may occur in association with lakes, rivers or with other wetland types such as marshes to form a large wetland complex. Marshes -Slough, prairie pothole, pond, fresh marsh, and emergent marsh are what we usually think of when someone mentions a wetlands There is usually an area of open water that may be deep or shallow. Plants, often cattails or bulrushes, emerge from the water, and the arrow-shaped leaves of Sagittaria species may be common near the edges. They store large amounts of floodwater, and support a wide variety of wildlife, including fish.
Marshes are especially attractive to birds, including loons, ducks, geese, herons, and egrets.
They are found in both prairie and forest areas of the state. Swamps may spread out for thousands of acres, and are especially common in northern Minnesota, where they intermingle with lakes, streams, bogs, and marshes. Many migrating bird species use swamps as rest stops, and woodpeckers search for insects in the abundant dead trees. Swamps are often pristine ecosystems, and support some of the state's rarest plant species, including ram's-head lady slipper and other orchids. Bogs -Peatland, muskeg, and moor are wetlands that form on a thick mat of peat covered by a layer of sphagnum moss that builds up above the water table.