The southbound migration of waterfowl, which begins in August, continues through November as interior lakes in Canada and Alaska freeze over. Buffleheads, one of our tiniest ducks, are part of this contingent. Known as “buffalo head,” especially in the past because of the odd puffy head shape, this diving duck is not just small, but also very buoyant, often appearing to bob up and down, even at the slightest riffles on the water.
How to spot one: Bufflehead males, small as they are, really catch your attention with their black-and-white pattern with a white patch on the back of their head. In sunlight and with a close view, what looks like black on the males’ head shines glossy green and purple.
The only other species that might momentarily be confused with a male bufflehead is the hooded merganser. But with a decent view a male bufflehead is a cinch to identify. Females are very different: overall darkish with a small patch of white on the side of their head.
When and where to look: Any deep pond or lake along the Yakima Greenway may attract buffleheads, which will linger until freeze-up. Farther afield, Clear Lake in the nearby Cascades is another excellent spot, as is Priest Rapids Lake, a slack water reservoir on the Columbia River on Yakima County’s eastern border.
Elsewhere, they are abundant on saltwater everywhere in Puget Sound, bays and estuaries along Washington’s coast and other lakes and shores throughout the United States south of Canada wherever waters remain open through the winter. Come spring, buffleheads head north to nest in boreal lakes as near as northeastern Washington and across much of Canada and north to central Alaska.
Chow time: In summer buffleheads feed mainly on aquatic insects, obtained mostly by diving. In winter, birds in saltwater dive mainly for crustaceans and mollusks.
Home life: Pairs begin forming in early winter when males start their ritualized courtship, which includes bobbing their heads, flapping their wings, uttering a purring grating call “grrr!” and ending with brief display flights. The female choses the nesting cavity, typically a disused woodpecker hole. A cavity in a dead tree close to the edge of a lake excavated by a northern flicker, a common woodpecker everywhere in the buffleheads’ breeding range, is perhaps the most common nesting site.
A lining of down feathers is the only nest material. She lays seven to ten eggs and does all the incubating for about a month. The male takes no part in incubating the eggs. After hatching, the female prods the young to drop from the nest by calling them a day or so after hatching. She leads the brood to productive feeding areas on the lake. They feed themselves but are closely guarded by the female. The young can fly after about seven weeks.
Buffleheads are still a common duck but are evidently much less numerous than a century ago. Unregulated shooting in the distant past and loss of snags around their nesting lakes are reasons cited for their decline.
• Wildlife Moment, focusing on native wildlife, typically runs in Outdoors on the first Thursday of the month, with the cooperation of the Yakima Valley Aububon Society.