A naturalist finds hope despite climate change in an era he calls 'The End of Eden'

South African naturalist Adam Welz traveled the world to understand how climate change is "weirding" ecosystems. One of his questions: How to stay hopeful in a warming world? (Brian Mann/NPR)

On a chilly morning this fall, Adam Welz wades through chest high grass in New York state's Adirondack Park, pausing often to scan with his binoculars and listen.

"That's a northern flicker, right?" he says. "That does the wok-wok-wok-wok!"