Each winter, tens of thousands of pronghorn, mule deer, elk, moose, and big-horned sheep congregate in Wyoming’s Upper Green River Valley to await the coming of spring. The ancient migration routes between this thriving valley and Grand Teton National Park are crucial to the wellbeing of these iconic species. Yet none migrate as far as the Grand Teton pronghorn, which cover 150 miles each way. Numbering only a few hundred, this herd relies on the Upper Green River Valley migration corridor for its very survival.

But runaway development in Wyoming, including oil and gas drilling, real estate sprawl, and fences, is taking a mounting toll on the Path of the Pronghorn. In some places, this vital corridor is just over 100 yards wide. Since the late 1990s, annual natural gas production in Wyoming has doubled, with more federal oil and gas drilling permits issued in the state in 2007 than in all other states combined. To make matters worse, the Bush administration is poised to approve plans that would allow tens of thousands more wells across Wyoming.

The U.S. Forest Service must designate a pronghorn migration corridor within the Bridger-Teton National Forest and permanently protect the Path of the Pronghorn.

Photo credits: Bear grass and moon at twilight, © Randy Beacham. Pronghorn Antelope, © Istock.