Earlier this month, a few Good Samaritans stumbled across a barbwire-trapped pronghorn antelope on the windswept plains of southern Montana. It took a little moxie and gruntwork, but the men were ultimately able to free the buck, tangled by its horns and a foreleg, from the fence.

The liberated pronghorn took off at a healthy pace, apparently not seriously injured.

"He relaxed enough to let us help him," the rescuers explained on YouTube. "We freed the animal and he seemed to run away unscathed."

Pronghorn are among the animal world's standout runners: in top speed falling not all that short of the cheetah, and leaving that lightning-fast big cat in the dust when it comes to endurance.

These sharply patterned ungulates (colloquially called "antelope", though they're not closely related to the true antelope of Africa and Asia) also undergo some of the longest migrations of any terrestrial mammal in the Western Hemisphere.

Fine-tuned on the oceanic prairies and sagebrush semi-deserts of western North America, the pronghorn's whirlwind ways and heroic wayfaring haven't meshed so well with the barbed-wire fencing that now cordons off those steppelands.

See, pronghorn – despite their mastery of both the dash and the marathon – aren't by nature jumpers. Unlike, say, mule deer, they won't usually hurdle over fences, even though they're capable. At the large scale, that can make fencing a major obstacle on age-old migratory corridors; at the small scale, it can see pronghorn shredding their backs trying to wriggle underneath a barbed strand – or getting snarled up completely.

This particular prairie speedster got lucky, but its rescue does spotlight the need to make fenced-off rangeland friendlier to pronghorn. Recent research suggests that even simple modifications to existing barbed wire may create less of an obstruction.

Researchers with the University of Montana, the Alberta Conservation Association and the Nature Conservancy tested a few different retrofits at habitual pronghorn crossing points in Montana and Alberta. They found that replacing the bottom strand of barbed wire with a length of smooth wire at the crossing point, or simply clipping the bottom wire to the next highest strand, facilitated easier pronghorn passage. (For whatever reason, pronghorn seemed wigged out by a third setup, which sheathed the bottom wire in PVC pipe; they wouldn't go under this so-called "goat bar", which has been touted as a wildlife-friendly fence upgrade for some time.)

These fixes – which, crucially, still make a fence a barrier to cattle – are especially promising because of how easy they are to install, and because pronghorn fidelity to specific crossing points means ranchers don't have to alter large lengths of fencing.

As Brian Martin, the Nature Conservancy's Grasslands Conservation Director, said in a Conservancy blogpost about the research, "Raising bottom fence wires with a clip can be a great first step in enhancing the passage for pronghorn, given how quickly it can be accomplished for a minimum cost."

Short of removing fencing altogether (we'd reckon the pronghorn's preferred choice), such solutions may help preserve the astonishing seasonal journeys of North America's fleetest beast.

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