A Bison Homecoming

Meet the Herd's Newest Member!

Born on May 13, 2010, and named Uno, she's the first calf to be born among the reintroduced bison herd.

A Bison Homecoming

View a slideshow of the bison and their new home.

Crossing Borders

Cross the U.S.-Mexico border with a herd of 23 bison and find out how they're helping restore grasslands in Mexico!


"If we miss the biggest part of the ecosystem — the bison — the restoration is not complete." 

Nélida Barajas
The Nature Conservancy’s representative in Chihuahua, Mexico

At last, here's a positive border-crossing story — about a U.S. bison herd that will help revitalize Mexico's grasslands, thanks to The Nature Conservancy and partners in both countries.

In early November, 23 bison barreled through livestock chutes and officially entered into Mexico in a controlled release — all under the watchful eye of officials from the Conservancy and the U.S. and Mexican governments.

The animals will be a “seed herd” for grassland recovery projects across Mexico. As their numbers grow through natural reproduction and donations of additional animals from the United States, they will be divided into groups and sent to other Mexican grasslands in need of their unique benefits to grasslands.

“Here are the bison that will recover all the grasslands of Mexico,” says Nélida Barajas, the Conservancy’s representative in Chihuahua, Mexico, as the animals stampede down the plank of the 18-wheeler that transported them to the border. 

The Missing Component

As they stomp the dusty earth and stretch their legs, these young bison seem blissfully unaware of the expectations on them. They still have 3 hours to travel to the Conservancy’s 46,000-acre El Uno Ecological Reserve in northern Mexico’s Janos Valley, where they will begin the daunting task of restoring the ecological and cultural values of this region.

Grasslands once stretched across North America from Canada through central Mexico, but they have been decimated by the growth of agriculture. The Conservancy is working throughout the Great Plains to restore these once-vast prairie lands through bison reintroductions and other grassland restoration efforts.

In Mexico, we’re collaborating with partners on efforts like invasive species control, native grass restoration, prescribed fire and grass-banking. But a key component has been lacking — until now.  

“If we miss the biggest part of the ecosystem — the bison — the restoration is not complete,” says Barajas, who worked for more than a year to coordinate this bison “adoption” between the U.S. National Park Service and a coalition of Mexican partners.

“We’re honored that they contacted us,” says Ken Hyde of Wind Cave National Park in South Dakota, where the bison originated. Hyde accompanied the bison on their 18-hour journey to the Mexican border. “This is an opportunity to use our bison to start a national herd.” 

(Read an interview with Wind Cave superintendent Vidal Davila about this donation of bison from the United States to Mexico.)

Why Are Bison So Good for Grasslands?

Bison, explains Barajas, bring a number of benefits to grasslands. When they walk they break the soil, so seeds can easily emerge. They also promote water infiltration, which is vital in an area where every drop of water makes a difference.

And they clip the grasses, keeping it the right height for other native species like prairie dog and ferrets to thrive.

“To restore the ecological functionality of the ecosystem," says Barajas, "we need to bring them back home.”

And there couldn’t be a better time to do so.
On Dec. 8, 2009, the Mexican federal government declared the 1.3 million-acre Janos Biosphere Reserve in the Janos Valley, home to some of the last, best examples of southern shortgrass prairie habitat in Mexico. The decree marks the first time that Mexico is officially protecting — and allocating resources toward — grasslands.

A Ranching Community: “We’re Recovering the Spirit of the Place”

But bison aren't just critical for grasslands — they are also part of the culture in this part of Mexico. Many local ranchers remember the last time they saw bison. In the nearby town of Janos, paintings of bison decorate the walls of the library and mayor’s office.

The Conservancy protected El Uno Ecological Reserve in 2005, with the help of Mexican partner Pronatura. The goal is to restore the grasslands and native species like the black-tailed prairie dog, as well as involve the surrounding community in sustainable ranching and agricultural practices that don’t overgraze the prairie or require intensive watering.

Now neighbors of Rancho El Uno are gathered to welcome the bison with a vaquero-style fiesta. Homemade tortillas are served up with bowls of beans and chorizo chili. Children peek through the fencing to watch the bison in their new pen.   

“This is something marvelous because bison used to be a part of our natural ecosystem,” says Manuel Prieto, a nearby rancher and president of the Janos ejido (a special category of land that is communally owned).

“Many animals, such as prairie dog, play a role in maintaining the ecological balance of the land, and the bison play a role, too. This is an important achievement for my country.”

Barajas takes it all in with a big smile. “This is a very romantic project. We’re recovering the spirit of the place.”

Tomorrow she will go to a local school where she’ll teach the children about how the bison used to roam the entire Janos Valley and their homecoming symbolizes the cultural legacy of the people who inhabit this region.

“The bison are returning not just for ecological reasons, but cultural and historical ones, too,” she explains. “You can’t tell the ecological story without the cultural one.”

Darci Palmquist is editorial manager for

(November 2009)


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