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 tiny and handsome Least Bittern is our only heron species with obviously different male and female plumages. Like many marsh-dwelling birds, it is threatened by habitat loss and wetland drainage. Audubon's climate model projects a 69 percent loss of current summer range by 2080, with a partially inland shift of summer range. The model also projects a distinct northward shift in winter range. However, most U.S. breeders currently winter in Middle America, so the predictions for winter expansion may yet be conservative.
Are the projected range maps different from the range maps in field guides? Find the answer here.