Two flocks of Bufflehead ducks, each more than a dozen strong, appeared this morning on the North Basin, easily visible from the east shore of Cesar Chavez Park.
The Bufflehead are the first waterfowl species of this fall/winter season to touch down here in significant numbers. Bufflehead migrate here from the northern boreal forests, or what’s left of them, where they nest in holes made by Northern Flicker woodpeckers.
Bufflehead are the smallest of the diving ducks. Their dives are usually short, 10-15 seconds. They’re looking for shrimp, crabs, snails and the like, but will eat some vegetable matter if required. They’re unique among ducks in being mostly monogamous, maintaining the same pair bonds for years. Here in winter, you can sometimes see the males engaged in vigorous dominance displays, rushing at one another and beating their wings.
Bufflehead males and females are easy to tell apart. The males have bright white hoods behind the eyes and their bellies are white. The females have a white spot behind the eyes on a dark brown head with a light brown belly.