Platte River, NebraskaThrough unyielding winds and icy rain, a long-legged, gray bird flaps its wings across the overcast Nebraska sky. Its squawk echoes an ancient call that has reverberated through this land for thousands of years. The bird is making its way to a dark cloud in the distance, one made of countless other birds—sandhill cranes, to be exact.

Each spring, roughly 600,000 sandhill cranes make their annual migration through Nebraska via the Central Flyway, a route also used by migrating ducks, geese, and shorebirds. The flyway is shaped like an hourglass stretching from as far south as Mexico to as far north as Siberia and cinched into an 80-mile-wide stretch in Nebraska. About 80 percent of migrating