Spring is a time of bird migrations, and one of the most spectacular involves the Sandhill Cranes. Half a million of these stately birds are making their annual stopover at the Platte River near Kearney, Nebraska, fattening up before they head to nesting sites farther north. It's the largest gathering of cranes in the world, and it's become a popular tourist attraction. But a 100-year drought, coupled with growing human demand for water, has put the Platte on the nation's most endangered rivers list. The cranes' dependence on the river adds urgency to the crisis.
Stars still sparkle in the Nebraska sky but a thin line of gray lights the eastern horizon as bird-lovers pile into school buses. Their destination: the Rowe Sanctuary, beside the wide and sandy Platte River. A man from Indiana explains that they're here for the dawn flight of the Sandhill Cranes. "This has been on my life list to see," he says. "It's an extraordinary experience just to see all that wonderful migration, and the birds washing themselves and preening and dancing for each other."
The red-capped, gray-feathered cranes are in the middle of an 8,000-kilometer migration toward nesting sites near the Arctic Circle. They stop at the Platte to fatten up on river snails and waste field corn, and they rest on sandbar islands that keep them safe from predators. This hundred-kilometer stretch of the Platte River is so critical to their survival, half a million cranes are crowded here. People getting on the bus say their sound is unforgettable.
"When they're all in chorus, it's just like kids getting out for recess. Thousands of kids...."
"Like a chill down your back. Like a Nebraska football touchdown against Colorado. Hee-hee."
"I do this once a year, because I'm born again. This is the greatest thing that happens to me. Once a year I come out here, and I can look forward to the next year."
Despite a major drought, the cranes are abundant near the Rowe Sanctuary Visitor Center, where the school bus finally stops. From the distance comes the cooing of cranes. It grows louder as the bird-lovers walk in the dim morning light through prairie grass, past cottonwood trees, then finally into a wooden viewing shed. The shed overlooks an enormous sandbar island, where 40,000 cranes have spent the night. Bathed in the pink light of dawn, a thousand cranes suddenly take flight.
Early 20th century conservationist, Aldo Leopold, described the call of the Sandhill Crane as the trumpet in the orchestra of evolution, our closest connection to prehistoric times. Steve Jones is co-author of a new Peterson's Field Guide about the American prairie, which features the Sandhill Crane migration.
"Cranes flew over the dinosaurs, and the Sandhill Cranes we're hearing now have been flying over central Nebraska for at least nine million years," Mr. Jones said. He adds that he's glad that these prehistoric birds thrive today. But as an expert on wild habitat, he worries. "This year the flow of Platte is the lowest I've ever seen it. So the habitat right now is marginal at best. And even though there are a half million cranes, 90 percent of the world's population, their future along the Platte will depend on our ability to keep the flows at least at a minimum and also to continue to provide islands for them to roost on in the center of the river."
For millions of years, sandbar islands were abundant in prairie rivers such as the Platte, thanks to spring floods that scoured the many shallow channels that flowed across the landscape. These days, says Mr. Jones, cities and farms draw out water for irrigation, and dams divert the ancient flows. "In the last century, we've controlled the flow of the Platte and we've reduced it, and as a result the Platte has become channelized, so it's lined with trees on both sides, and the islands are choked with vegetation," he said.
To keep the crane roosts open, ecologists cut and burn shrubbery off the islands. Paul Tebbel manages the Rowe Sanctuary. He says that bulldozing shrubbery helps the cranes, but their survival remains precarious. "We do 23 miles [37 kilometers] worth of it, which is just a band-aid, drop-in-the-bucket approach. It's dismal by comparison to what Mother Nature used to do with water," he said. "In the fifth year of a drought, all the water's being saved for the farmers. In the summer, this river will go dry, and all the water that is available will be used for irrigation. It's just the difficulties of trying to manage an over-appropriated river. There are too many demands and not enough water."
For the first time ever, farmers across Nebraska face limitations on how much they can pump from the Platte River basin. Saving water for migrating birds may take more sacrifice. But as this retired farmer recalls their morning flight, he says the cranes are worth it. "That's one of the reasons I loved farming, is because of all the birds that we had," the farmer said.
Farmers and town leaders are working with conservationists in Nebraska to protect the livelihood of farmers, the economy of rural towns and the habitat of the cranes, through innovative water conservation, and long-range planning to get through droughts. These steps could make all the difference for the future of the Platte River, and the ancient migrations of the Sandhill Cranes.