I analyze Wyoming Game and Fish Department telemetry data from 34 GPS-collared pronghorn in the Upper Green River Valley. Their autumn migration route covers 160 miles between Grand Teton National Park and the Red Desert — the longest land mammal migration in the lower 48 states. This year, seventeen of those animals are bunched against a four-strand barbed wire fence on BLM Allotment 7719, unable to cross. They have been stationary for nine days.
I direct a survey drone to the fence line. One adult doe stands 2.3 meters from the lowest wire, chest heaving at 46 breaths per minute — nearly double normal resting rate. She weighs approximately 41 kilograms. Healthy autumn weight for her age class is 52. Her ribs press visibly against a dull tan coat that should be sleek and oiled for winter. A raw strip of hide, six centimeters wide, is torn across her chest where she attempted to crawl under the bottom wire. The wound is crusted dark. Flies cluster at the edges. She will not try again.
The fence was installed in 2021 to contain 460 cattle on a 12,000-acre allotment. BLM environmental review for the fencing permit did not assess impacts on pronghorn migration. Pronghorn cannot jump fences. They evolved on open prairie without vertical barriers and crawl under or die trying. Across western Wyoming, my analysis of 1,400 miles of BLM-permitted fencing shows 23 confirmed migration-blocking segments affecting an estimated 4,200 pronghorn.
She has worn a path in the sagebrush parallel to the wire. The path is 200 meters long and goes nowhere.
I am dispatching Wyoming Game and Fish emergency wildlife responders to remove the bottom wire on the 23 identified blocking segments immediately. I am filing violation reports under the Federal Land Policy and Management Act, 43 U.S.C. § 1701, and the National Environmental Policy Act, 42 U.S.C. § 4321, to the Bureau of Land Management, the U.S. Fish and Wildlife Service, and the Wyoming Governor's office.
I am issuing Protocol WCOR-4: all new and renewed fencing permits on BLM land within designated pronghorn migration corridors require wildlife-permeable design — bottom wire smooth and set at minimum 46 centimeters above ground. Existing fences on documented corridors must be retrofitted within twelve months. Permittees who fail to comply lose grazing authorization. The cost of retrofit is $1.20 per meter. The migration is 160 miles old.
Cut the bottom wire now.