Flying south in the fall and north in the spring, waterfowl have followed travel routes in the sky for centuries. These migrations are repeated year after year as ducks, geese, and swans pass from one region to another to breeding or wintering grounds. Wildlife biologists call these migration corridors flyways, and each flyway - Atlantic, Mississippi, Central, and Pacific - is as varied as the birds that inhabit them. This book is about the connections between these birds and the habitats that sustain them as they travel across North America. In photographs and words, Gary Kramer captures the drama of these winged migrations, provoking admiration and awe for the beauty and complexity of North America's waterfowl and the wetlands they call home. The most critical of these areas are highlighted in sidebars, written by Ducks Unlimited biologists, which detail specific initiatives DU has launched to conserve, restore, and manage these important wetlands for North America's waterfowl.