THE TRAP WAS SET BEFORE SUNRISE on a crisp, sunny morning in late February. From the helicopter where New Mexico pronghorn biologist Anthony Opatz watched, it resembled wings spread across the prairie, with wide lines drawn by fences in the dun-colored grass. The aim was to collect scattered groups of pronghorn, the reddish-brown-and-white horned ungulate native to New Mexico’s grasslands, in a circle of tarpaulin walls and metal fences. From there, they’d be loaded into trailers and transported across the state.
Getting to this moment had taken Opatz a year. He had negotiated with a private landowner who had a robust herd of pronghorn on his ranch, wrangled equipment and supplies, helped build a trap firm enough to hold a rushing herd, and assembled a team of roughly 60 New Mexico Game and Fish Department staff for a three-day job. He’d had to call it off once, when melting snow turned the ranch’s dirt roads to slippery mud. But a week later, with chase crews in trucks and more people hiding in freshly dug pits, Opatz climbed into the helicopter to catch the continent’s fastest land mammal.
The first European explorers to the plains of the American West, where pronghorn roam from Mexico to Canada, encountered herds that might have numbered as many as 35 million, nearly as abundant as the bison known for stalling westbound wagon trains for days. Pronghorn are an Ice Age
