Green-winged Teal, Hillsboro, Oregon on January 2010 by Greg Gillson.
The Green-winged Teal is a tiny duck that is a rather common migant and winter visitor throughout the Pacific NW. It breeds east of the Cascades in grassy marshes. Small numbers are often found in summer west of the Cascades, and while breeding has occurred, actual nesting records are sparse.
Males give a distinctive piping whistle call, while females give a quiet series of quacks.
These smallest of North American ducks feed on seeds of grasses and sedges, as well as taking some invertebrates.
Besides the small size, the males are identified by the white vertical stripe on the gray side of the breast. They have a chestnut head with green eye patch. The sides of the undertail coverts are buffy yellow, the remainder of the undertail coverts black. Females are mottled brown with a dark crown and a dark line through the eye. Both sexes show a green wing patch on the secondary flight feathers.
Like all dabbling (or puddle) ducks, these birds tip up to feed, rather than dive. They also spring from the water directly into flight, rather than running to take off as the diving/bay ducks.