The Park

Green Lake’s Changing of the Guard: The American Coot

November 17, 2014 6:53am

unnamed-3If you’ve walked the lake recently you’ve probably noticed a changing of the guard. Several new birds are busily floating, bobbing and diving into the lake that weren’t there several weeks ago. So what gives? Who are these stout black birds with white beaks? We asked our go-to nature expert Martin Muller for some insight about these waterfowl that emit the unusual little sounds.

This is the American Coot (Fulica americana), not a duck at all, but rather a relative of rails (Sora, Virginia Rail) and cranes (such as Sandhill Cranes, for example). These vegetarians are quite good divers (as opposed to dabbling ducks that only tip and stretch their necks to reach as deep as they can without actually diving; Mallard, American Wigeon, Gadwall, for instance). Coots can reach depths of 60 feet, which means they can reach the bottom of Green Lake, even where the deepest point is 28 feet.

You will often see American Wigeons and Gadwals accompanying the coots out in the lake. As temperatures drop and aquatic plants die back, the wigeons and Gadwalls have more and more trouble reaching the plants. They then hang around the coots and try and pilfer some as the coots come up with a beak-full. As winter progresses the coots come up with smaller and smaller bits of plant material, to the point where the wigeons and gadwalls prefer to start grazing on land.

Coots will also graze on land, which provides a great opportunity to study their feet that have partial webbing (lobed toes). The lobes help propel the birds both at the surface and below the surface. They also help distribute their weight as they walk through marshy areas, such as where they nest in dense marsh vegetation.

So now we know! Thanks Martin!

You can check out more about the winter birds of Green Lake on Martin’s blog.