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.
Swamp Sparrows are common and well-known to birders across most of eastern North America. Audubon's climate model projects a 69 percent loss of current summer range by 2080, shifting north dramatically. During the winter, the species is stable and has some potential to expand northward. A warming climate and an increase in sea level are almost certainly bad news for the already threatened and distinctive resident population (nigrescens) found in saltmarshes along the U.S. Mid-Atlantic coast; the model doesn’t address this population.