Yellowstone’s long-distance travelers in trouble, study says

Populations of antelope, elk and deer face growing gauntlet of gas fields and highways

Bottlenecks from increased development are choking off ancient migration routes for wildlife in the Greater Yellowstone Ecosystem (GYE) and other regions, according to a study by the New York-based Wildlife Conservation Society (WCS) that appears in the current issue of the journal Conservation Biology.

Increased gas development in particular is making it more and more difficult for species like pronghorn antelope to migrate in and out of Yellowstone National Park, a round-trip of 340-miles – the longest of any land-based mammal from Argentina to Toronto. Its current winter migration route consist is a perilous network of narrow mountain passes to 100-yard-wide strips along highways. Carbon dating by archeologists shows that some of these routes have been used for 5,800-7,800 years, according the authors.

“From wildebeest in Africa to antelope in Wyoming, long distance migrations are one of the world’s most stunning yet imperiled biological phenomena,” said the study’s lead author Dr. Joel Berger, a WCS biologist based at a field office in Moose, Wyoming. “Here in the U.S., pronghorn and other species are in jeopardy of losing what little migratory ability they have left.”

According to the authors, approximately 8,500 energy-extraction sites exist on public lands in southwestern Wyoming, just below the Greater Yellowstone Ecosystem, the 40,000 square-mile region surrounding Yellowstone and Grand Teton National Parks. An additional 15,000 more are planned for the next decade, according to Berger. The effects of this spate of drilling activity on antelope, and other migratory species including elk and mule deer, are largely unknown.

“Unlike the plethora of Alaskan studies designed to understand possible petroleum-related disruption to migratory caribou, no scientific literature exists to assess possible energy-related effects on migration in the GYE,” Berger said.

To protect these traditional migrations, the authors of the study suggest that a network of strategically planned protected migration corridors should be established.