n this May morning a relentless, shivering spring rain falls on Glacier National Park. It’s the kind of rain that shrivels your skin and dissolves the last stubborn remnants of snow clinging to the shaded corners of this jagged landscape. At the soggy edge of Upper McDonald Creek, a hearty group of volunteers braces against the cold, preparing to scour the muted landscape in search of a creature that takes great pains to remain hidden. It’s not one of the superstars of Glacier they seek—the grizzly, bighorn, or mountain goat—but a one-and-a-half pound sea duck called the harlequin.
Named for the raucous acrobatic clown of 16th-century Italian theater, the harlequin duck bears some of the most striking markings of any waterfowl. As with most ducks, the hen’s plumage is fairly drab and nondescript—aside from her small size and a distinctive white patch on the side of her head, she’s quite likely to be overlooked by the casual observer. But the costume of the flamboyant drake in breeding season calls to mind a mime who has downed a quart of espresso before applying his makeup. The male’s deep slate blue feathers are painted with bright auburn patches on his belly and head, while white bands and dots dapple the drake’s face, chest, and back.
Appearance is one in a long list of attributes that make the harlequin unique. Foremost among these may be its penchant for perilous places. This duck earns its bread and butter in places most creatures avoid, and like its namesake, the harlequin exhibits an acrobat’s agility in its unusual ecological niche—whitewater.
Sea ducks generally favor sheltered lagoons or open ocean, but the harlequin’s coastal wintering grounds are filled with the thunderous sound of surf, and the same roaring rapids characterize its preferred breeding habitat. Appar-ently the harlequin realized that no other creature was taking advantage of the cornucopia of tasty and nutritious critters that dwell where water and air collide in a violent tumble.
It is at this elemental crossroads that a group of volunteers will spend the day. They’ll be trekking along a muddy nine-mile stretch of the creek, over downed logs and around dense creekside brush. They’ll scan every inch of the assigned route, hoping to identify each and every harlequin, a creature that seems capable of fading into the scenery at will.
Population surveys of the harlequin have been ongoing since the early 1990s, when alarm bells sounded the decline of this secretive Glacier resident, one of the least studied birds in North America. In the early years, the counts were conducted primarily by park staff and trained biologists, but funding shortfalls have led park researchers to enlist volunteers in the search for clues to a complex and disturbing puzzle: Why and to what extent are the harlequins in decline? Could conditions at the park be responsible for the downturn? And what does their decline mean for the entire Glacier ecosystem?
According to Steve Gniadek, a veteran wildlife biologist who has spearheaded the project for more than 15 years, information on Glacier’s population of harlequins is spotty at best. Biologists are confident that the ducks nest along McDonald Creek, but they’ve never actually set their eyes on a nest inside the park. It’s possible the ducks’ decline came about after harlequins abandoned suitable nesting habitat because of visitor disturbance, but until researchers know where the nests are—or even where they once were—it’s any-body’s guess whether human impact plays a role.
Mystery comes with the territory: Because harlequins generally nest along the ground, they must stay well hidden from predators or risk their very survival. In Alaska, where the harlequin’s population is believed to be quite high, only a handful of nests have been found.
Even in an ideal world, there may not be many nests to see. Harlequins are slow to reach breeding age and may not mate until they are three to five years old; only 50 percent of females nest each year. Harlequins generally lay four to seven eggs, compared with eight to 12 for the ubiquitous mallard. Harlequin eggs incubate for about a month, and only four are likely to live to maturity. Although many drakes remain with the hen and eggs for some time, the harlequin drake returns to the wintering grounds as soon as the eggs are laid. If a predator should steal the eggs or any other mishap should claim them, there’s no chance of the pair breeding again for an entire year.
