Coots are not ducks, although they do swim like them. Like the grebes, coots, have lobed toes, rather than webbed feet, but coots aren’t closely related to grebes either. Rather, they are members of the rail family (in the genus Fulica). Coots have slate-like plumage: grays and blacks, except their white bill. Coots swim in the open water (and so are easy to see).
Coots are winter visitors to the Lake, and are gone by the end of March.
With a slate body, black head and ivory bill, the coot looks unlike any other swimming bird. They are further distinguished by a large reddish-brown spot on the base of the bill between their eyes.
A Coot must run across the water to gain speed to get airborne. When flying, the bird, reveals things not seen when it is swimming: the white patches on its wings; its lobed toes.
Coots gather in a large group along the Nelson waterfront during the winter. What attracts them to this location in particular (as opposed to the rest of the West Arm) is not the least bit obvious.
Information from Wikipedia: American Coot.