The darker the color, the more favorable the climate conditions are for survival. The outlined areas represent approximate current range for each season. More on reading these maps.
The Red-breasted Merganser is circumpolar in distribution—that is, it’s found across Eurasia as well as in North America, all the way around the pole. Audubon's climate model predicts that more than three-quarters of its North American summer range is projected to shift north by 2080. Large numbers of the species winter offshore, complicating interpretation of the winter range projection, which on its face shows stable numbers and—not surprisingly—a northward shift in range. Large winter concentrations will likely remain on the Great Lakes.