Favours rocky shorelines of rapid streams, frequents coastal estuaries and islands. East and West Coasts of North America Harlequin ducks are named for the ornate, clown-like appearance of the males. Females are well-camouflaged in basic brown.
Eastern range extends from Greenland and Labrador as far south as New Jersey.
Western range is from Kamchatka Peninsula and Siberia north across the Bering Strait and back down through Alaska, inland throughout much of the Rockies, and as far south as the central California coast. The ranges are seperate and populations are much higher in the west. Some southward migration takes place but most movement is inland for breeding and nesting and seaward for wintering.