Two-Year Study Into Harlequin Ducks In Glacier National Park Getting Under Way

A two-year study is getting under way into the nesting habits of harlequin ducks in Glacier National Park. NPS photo.

One of the most beatiful ducks is the harlequin, a strikingly handsome waterfowl that prefers swift-moving waters. Though typically found along coastlines, these ducks do come inland quite a way, as demonstrated by those that show up in Glacier and even Yellowstone national parks.

Males, with their slate-gray or gun metal blue plummage contrasted by white patches in front of their eyes and black-bordered white slashes just in front of rusty-brown wing feathers, are particularly handsome. They also can be hard to see if you're not looking specifically for them.

At Glacier, these medium-sized ducks frequent Upper McDonald Creek, and researchers are getting ready to launch a 2-year study to better understand their nesting habits with hopes of increasing both nesting success and chick survival.

Park biologists and researchers from the University of Montana plan to use radio-telemetry and banding to monitor the ducks. The project is being jointly funded by the Federal Highway Administration and a grant provided through the National Park Service Rocky Mountains Cooperative Ecosystem Studies Unit.

According to a park release, harlequin ducks, a species of concern in Montana, "occupy a unique niche among waterfowl. These small sea ducks spend most of their lives feeding in the turbulent surf along the North American coast. Each April, the ducks migrate inland to breed and raise their young along fast-moving, freshwater streams."

"They are specially adapted to feed on stream bottoms in raging water, a place inaccessible to other wildlife species," the release added.

This duck species, though, is at high risk of local extinction due to its very limited numbers, limited habitat, overhunting (occurring outside the state), sensitivity to disturbance, and habitat loss or alteration, the release said. The impacts of climate change and consequent changes in spring runoff are also of serious concern for this species.

Harlequins occur on only a limited number of streams in Montana; more than 25 percent of all harlequin duck chicks produced in the state are raised along Upper McDonald Creek, the park noted.