Photo: Kelly Colgan Azar / cc In recent decades, birdwatchers in North Carolina have had to travel farther and farther north to catch a glimpse of their beloved wrens and waxwings, and scientists suggest that changes in the climate could be to blame for the birds' relocation in the winter. According to researchers, many birds species that were once common in the region around Charlotte have moved northward as temperatures in the region continue to increase -- on average, a whopping 116 miles away -- but global warming may not be the only reason why...Read the full story on TreeHugger