Designed to outrun saber-toothed cats as well as other ancient predators, and now, the coyotes and wolves that prowl the prairie, the pronghorn can reach a top speed of nearly 100 kilometres an hour.
That makes the antelope-like creature the fastest land mammal in North America and second only to the cheetah in the world.
But evolution didn't adapt the pronghorn to the modern face of the prairie. The traditional range of these fleet-footed nomads has steadily been chopped up by fences, railways and roads, as well as industrial plots for oil, gas and coal.
“Pronghorn don't jump fences,” said Michael Suitor, a researcher at the University of Calgary, “That's the short and skinny of it. They evolved out on open prairie … But since fences have been popping up everywhere, it causes them considerable grief.”
Pronghorns have been found tangled in fences and maimed by them. Mass deaths at fence lines have also been reported as pronghorn failed to find a way around or underneath the barriers.
Now, an unlikely coalition of conservationists, hunters, landowners, government, business and the military in Alberta is working to change that. Together they are spending about $300,000 mending fences. So far, almost 200 km of pronghorn-friendly fences have been installed in a key migration corridor for a species once nearly wiped off the planet.
“They're an icon for the Prairies,” said Paul Jones, a biologist with Alberta Conservation Association, which has helped fund the project with levies collected from anglers and hunters. “We no longer have bison free roaming across the Prairies. These are sort of the last large mammal roaming on the Prairies.”
In the early 1800s, an estimated 35 million bison were grazing the continent – the same as the population of pronghorn ranging from Alberta and Saskatchewan through the western United States and into northern Mexico.
Both suffered from rampant hunting and habitant destruction and by 1924, just 20,000 pronghorn remained. Protection efforts have helped the species bounce back.
The World Conservation Union's Red List of threatened species now counts 500,000 to a million pronghorn. Unlike threatened bison, the group didn't express concern about pronghorn survival, but noted that they are hurt by severe droughts and tough winters.
During the cruel winter of 1995-96, the pronghorn population in Alberta was cut in half to about 9,600, according to experts.
Mr. Suitor, who placed GPS collars on pronghorn to study migration patterns, found the animals would travel 150 to 250 km in just weeks, but also that barriers would trip them up.
Low-hanging barbed wire was tearing hair from their backs, often leaving bald spots exposed to frostbite. Dead animals were found caught in fences. During bad weather, fences can hinder the search for food and water.
“We've had instances of hundreds if not thousands of pronghorn dying during those occasions,” Mr. Suitor said.
Trains and roads lined by fences present more obstacles. “We've had a couple hundred taken out in one swipe of a train,” Mr. Suitor said.
He also found bottlenecks. Paths were beaten into the ground where pronghorn funnelled in to the easiest sections of fence. Some animals would spend days moving along the Trans-Canada Highway before finding a place to cross. He noticed one doe spent 10 days trying to cross the country's main east-west artery.
Concerns have been raised in Canada and the United States about the impact of energy production on pronghorn habitat. Some research has shown that drilling forces the animals to wander beyond their home ranges.
The U.S.-based National Wildlife Federation is trying to prevent coal-bed methane development and a massive wind farm from going up in an area of Wyoming known as the pronghorn heartland.
