Animal migration occurs all around us and yet remains a mystery

by Michelle Nijhuis

Every spring and fall, I'm surprised by an odd sound above my house in Colorado. It's somewhere between a creak and a hoot, an eerie, echoing call, like the one I imagine some dinosaurs used to make. It always takes me a minute to place it, but suddenly it's unmistakable: It's the sound of sandhill cranes, on their way to Yellowstone in the spring or central New Mexico in the fall. The cranes are hard to find in the sky, invisible until the sun flashes on a wing and my eyes adjust to the birds' altitude, thousands of feet above the ground. Then, there they are, dozens flying in their familiar V.

Animal migration happens all around us, but we rarely glimpse more than a snapshot of the journey. We might know, vaguely, where the animals are going, or perhaps where they came from, but we almost never travel with them. In 2008, when the U.S. Forest Service established the first -- and so far only -- national migration corridor, protecting part of a 120-mile-long migration route for pronghorn in Wyoming, most of us saw the dramatic journey as simply a long line on a map, a constellation of data points collected from satellite collars. Even today, only the very lucky or very persistent get more than a glimpse of these pronghorn during their extraordinary seasonal struggle through the mountains.

For four seasons, freelance writer and former HCN editorial fellow Emilene Ostlind tried to see this pronghorn migration -- really see it --- firsthand. She followed the path of the Teton herd in western Wyoming, searching for them in the Gros Ventre Mountains and at creek crossings accessible only by foot. She got lost in drainages, battled through thick brush, and post-holed her way through deep snow. Over many miles, she slowly learned the landscape, much the way the pronghorn fawns do as they follow their mothers along the migration route. Ostlind learned a lot about pronghorn endurance and gained a new understanding of the importance of migration to the species' survival. And she saw ... well, I'll let her tell you what she saw. Photographer Joe Riis, who worked and hiked with Ostlind during her research, used camera traps to produce the stunning images that accompany her story.

Also in this issue, freelance writer Mary Ellen Hannibal looks at the complex science and policy of wildlife corridors, and wonders why the Path of the Pronghorn remains our only nationally recognized and protected migration corridor. Finally, HCN Assistant Editor Cally Carswell reports on the role of private-land conservation in the protection of pronghorn and other wildlife migration corridors, and on some ongoing efforts to preserve connectivity across privately owned landscapes.

Migration, our writers agree, is still in many ways a mystery. But the closer we look, the more amazing the view.

© High Country News