Yellowstone National Park is home to birds of every feather. Some have adapted to tolerate its cruel subzero winter months, while others come from distant horizons to make the most of its summer bounties. But regardless of the season, survival here is no easy feat in a land ruled by giants and governed by extremes. Follow Yellowstone's winged creatures as they hunt over vast canyons, guard the wetlands, and help their young take their maiden voyages over one of the greatest wildernesses on Earth.