Saturday, May 26, 2012

Harlequin Duck Highlights

Harlequin Duck pair (c) John Ashley
A pair of Harlequin Ducks rests on a mossy boulder in Glacier National Park in late May.

Right now is the most critical time of the whole year for Harlequin Ducks breeding in Montana. When they're old enough to pair up, the females return to the stream where they were born. The younger females are currently scouting for a future nest site, but most will return to the coast without nesting this year. The older females already knew where they were going to nest before they even arrived this spring. Most likely, some of the older hens are currently laying their eggs, one egg every 1-3 days, and will begin to incubate them after the last egg is laid.

Male Harlequin Duck in rapids
(c) John Ashley
Male Harlequin Duck in rapids
Up in the McDonald drainage of Glacier National Park, we have attached tiny, temporary radio transmitters to a dozen paired females as part of a three-year study. In a couple of weeks, we will attempt to locate their nests by following the radio signal. It's much more difficult than it sounds, as Harlequins are very secretive nesters. Last year, we also had 12 hens with radios, but we only found two nests.