Don Welch is a Nebraska poet and author, recently retired from 50 years of teaching at the University of Nebraska at Kearney. He’s lived most of his life with his wife Marcia in central Nebraska, where much of his work has been influenced by the natural world.

In the predawn hours of an early Saturday in April, cars creep quietly along a gravel road south of the Platte River’s main channel. For the last half hour, the dark sky has nibbled away at the edge of the full moon above, the lucky occurrence of a rare lunar eclipse.

Few modern species can lay claim to older origins than the sandhill crane. Each spring, 80 percent of the mid-continent population spends a few weeks along the central stretch of the Platte River in Nebraska. But this unprecedented concentration of birds on the Platte represents a challenged ecosystem.

Twice a year, the world’s largest remaining wild population of endangered whooping cranes makes the 2,500-mile journey between breeding grounds in Canada’s Northwest Territories and wintering grounds on the Texas Gulf Coast, using the Great Plains as their migratory corridor. Biologist are tracking these rare birds to learn more about their migration.