A Rare Look at an Incredible Animal Migration

At just 30 years old, National Geographic photographer Joe Riis has devoted his life to documenting—for the first time—the Grand Teton pronghorn migrations in the American West. His work has helped to create corridors and road crossings that allow these animals the freedom to move as they have for thousands of years.

Click here to read more about Joe Riis and his work protecting animal migration

Click here to see photos of the overpass that's helping pronghorn migration