JANOS, Chihuahua - The wild bison herd standing in the golden grass looked like they stepped out of a painting of the Old West. But this was Northern Mexico and these bison are part of a modern day effort to restore native grasslands.
"There's one of the males," said Jose Luis Garcia Loya, pointing to one of the largest animals. Garcia Loya runs Rancho El Uno, an ecological reserve about 80 miles south of the border.
The enormous male, officially known as 17, is nicknamed "Big Show" by Loya's 14-year-old son.
The majestic animals, also known as buffalo, once roamed North America by the millions, and their vast territory stretched into Northern Mexico. Bison were hunted to near extinction in the 1800s.
Now, the U.S. and Mexico have teamed up to bring wild bison back. Nearly 46,000 acres at Rancho El Uno are part of an ambitious plan by the Nature Conservancy to restore grasslands destroyed by overgrazing.
The Nature Conservancy also has wild bison in the United States in South Dakota, Missouri and Iowa.
The herd in Janos did not migrate across the prairie. It started with 23 animals trucked across the border in 2010 from South Dakota.
"This was once bison territory, "said Garcia Loya as he looked through binoculars at the bison walking through the grass.
Unlike cattle, which stay and feed to the root, bison eat and roam, leaving some of the plant intact. Their heavy step breaks up the soil and helps grass seeds grow.
A three-year study by the International Union for the Conservation of Nature found restoring wild bison to their historic range would benefit the land in Canada, the United States and Mexico.
"The grass used to be tall," said local rancher Angel Martinez, 67, describing the Janos area when he was a boy. "But too much cattle, overgrazing left it all ugly," said Martinez, gesturing to barren patches of land in the distance.
To rescue native grasslands, Mexico's conservationists had to win over skeptical cattle ranchers in the region. El Uno opened it's doors to ranchers in the area and invited everyone in the town to celebrate the bison release.
"At first we questioned why those crazy people brought the bison back," said Manuel Yanez, local rancher, laughing.
But as they started to see results, Yanez and his father-in-law Martinez joined a group of ranchers who adopted sustainable grazing practices.
They now raise smaller herds. And when the pasture recovered, they no longer had to truck in alfalfa -- which was expensive during the drought.
"The bad years, but we made things worse," said Yanez about the practice of overgrazing.
Mexico's president declared the 1.3 million acres surrounding Rancho El Uno a federally protected area and named it the Janos Biosphere Reserve.
The ranch is now cultivating the next generation of conservationists. Students in the area started their own ecological clubs after a field trip to see the bison.
"Something you don't see every day," said Jessica Garcia, 14, a student who belongs to one of the clubs. "It's very cool."
"There are very few. We have to take care of them," said Viridiana Briseno, 11, of the bison that make their home at Rancho El Uno.
The herd is growing nearly three years after the 23 bison arrived in Mexico in 2010. There are now 37 animals.
"Come Uno!" Garcia Loya calls out his favorite bison named "Uno" -- number one because she is the first wild bison born at the ecological reserve.
Now there's hope that she's pregnant and will give birth this spring - continuing the centuries-old bloodline behind modern day conservation efforts.
Garcia Loya says many of the females in the herd will probably become mothers.
"I'm pleased with what we've been able to achieve," he said.