For 20,000 years, spring rains and melting snow have filled the playas of the Rainwater Basin of south-central Nebraska. As winter ends, 10 million waterfowl rest and feed there before continuing north. The seasonal wetlands form a funnel for birds heading from the Gulf Coast and points south to northern breeding grounds. In recent years, the number of Snow Geese stopping there in spring has risen dramatically to more than three million birds. A third of North America's Northern Pintails rely on the food-rich habitat there. Twenty-seven species of shorebirds use the wetlands, as well as half a million Sandhill Cranes.More info and transcript at BirdNote.org. Want more BirdNote? Subscribe to our weekly newsletter. Sign up for BirdNote+ to get ad-free listening and other perks. BirdNote is a nonprofit. Your tax-deductible gift makes these shows possible.