Bird Lore: Surf Scoter

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surf_scoter_drake

The Surf Scoter is a diving sea duck that can be seen along the Edmonds waterfront in fall and winter. The winter flock starts to build in September, usually with some ducks seen flying by. Then a few are seen on the water and the winter flock seems to grow day by day. Early in the season the flock moves around the ferry dock and Underwater Park, just to the north. Later in the season the scoters spend more time around the public pier. This scoter can be found along all contiguous U.S. coastlines in winter. It is partial to coastal bays, harbors and fishing piers.

The drake is a handsome fellow, dressed in black with a white patch on his forehead and another on the nape of his neck. The colorful large bill, mostly orange, is a head turner. The female and young have plumage that is drab brown. The adult hen has poorly-defined white patches on her head and her crown is darker than the rest of her head and neck. Immature birds have more distinct white face patches.

surf_scoter_hen

The Surf Scoter eats mostly mollusks but will supplement its diet with crustaceans, aquatic insects, small fishes and marine worms. Although it is a diving duck, it shares some characteristics with the dabbling ducks in that it eats some plant materials such as pondweeds and sedges. When this scoter does dive, it does so by springing forward and diving with its wings partly spread. It then propels itself underwater with its feet and with its wings half opened. It forages for prey on or near the bottom.

Pairs form in winter. Several drakes may court a hen. Their courtship displays include swimming rapidly back and forth, with necks stretched upward, exaggerated bowing, and short display flights. The drakes will also pursue a hen underwater. Breeding grounds cover much of Alaska and the northern tier of Canada. The female builds the nest on the ground, some distance from water. It is just a shallow depression lined with down and is well hidden in a clump of grass or under low tree branches. The hen lays 5 – 9 eggs and incubates them by herself. Shortly after hatching, the young leave the nest and go to water. Although the hen tends them, they feed themselves with a diet of aquatic insects and plant materials. On crowded lakes it is common to have accidental exchanges of young among the broods. Evolutionary selection to prevent these mixups is thought to be weak because the female provides no care other than guarding the chicks. The age of first flight is not known.

Conservation status of the Surf Scoter is that of least concern. It is considered a common duck but whose population may be declining.

You can listen to the sound of wingbeats and display calls of drakes at this site: http://www.xeno-canto.org/76453.

— By Carol Riddell

Carol Riddell manages the bird education displays, on behalf of Pilchuck Audubon Society and Edmonds Parks & Recreation, at the Olympic Beach Visitor Station.

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