Gadwalls.
At 18 to 21 inches they are medium-sized ducks. The male is grayish with a white pach on the back edge of the wing, a black rump and sandy-brown head. The female is mottled brown with a white patch of the back edge of the wing.
They inhabit freshwater marshes, ponds and rivers. They can also be found locally in salt marshes.
They range from southern Alaska to Minnesoata south to California in the west and western Texas in the east. They can also be found locally in the eastern US. They winter in much of the central and southern United States.
Sterling State Park, Monrow County, Michigan.