In a June 2019 article published in Nature Climate Change, researchers concluded that the “northernmost spatial regime boundary” for birds in the Great Plains of North America has shifted to the north by more than 350 miles over the past forty-six years, an indication of rapid global change. “Climate change, anthropogenic pressures, wildfire trends, and woody plant invasions,” according to the researchers, “have all operated along a putatively south-to-north trajectory over the past decades.”