American Coot, related to Common and Purple Gallinules. They aren't really a duck, though people think of them as ducks. They lack webbed feet. They have really big feet, though. With them they are able to walk on lily pads and other growth that's in or near the surface of water. Coots, unlike Gallinules are often in really big flocks of anywhwere from 50-100 or more. Maine has American coots but for the most part in the summer months as they are migratory here.