Hunted out of northern Mexico roughly 200 years ago, American bison are back, and hidden cameras are already recording pumas, lynxes, and collared peccaries returning alongside them.

  • 47 bison reintroduced to Mexico's Cuatrociénegas region since August 2025
  • 44 of them relocated in November 2025 from the Janos Biosphere Reserve herd in Chihuahua
  • ~200 years since bison were extirpated from the area
  • 4,000 hectares of the El Santuario reserve now home to the new herd

A keystone species comes home

In August 2025, three bison stepped into El Santuario, a reserve within the UNESCO-recognized Cuatrociénegas basin in Coahuila. It was a symbolic start. In November, a coalition of conservation groups, including Fundación Pro Cuatrociénegas, Cuenca Los Ojos, Mexico's national parks commission CONANP, and the Mexican Fund for the Conservation of Nature, moved 44 more animals in from the Janos Biosphere Reserve, bringing the region's total past 47.

Bison had vanished from the Chihuahuan Desert around two centuries ago, hunted to local extinction. Gerardo Ruiz Smith, director of the Fundación Pro Cuatrociénegas, called their return a historic moment after roughly 200 years.

"It offers you so much hope," Ruiz Smith told the Mexican outlet Vanguardia, describing the impact of simply bringing back "a fundamental species that was there before and should be there."

Rangers are already seeing the difference

Bison are ecosystem engineers. Weighing up to 1,700 pounds, they till soil with their hooves as they move, opening the ground to water infiltration. Their grazing thins dry vegetation that would otherwise fuel wildfires, and their manure draws dung beetles that aerate and fertilize the soil.

"They set about molding and regenerating their surroundings," Ruiz Smith told CNN en Español.

Seeds get tangled in their fur and scattered as they roam. Local birds have started using bison fur to line their nests. And according to Ruiz Smith, hidden cameras in El Santuario have already picked up the return of pumas, lynxes, and collared peccary, species that had been largely absent from the area, per reporting from AS USA.

Part of a bigger strategy

The relocation is one piece of a four-part Mexican conservation strategy: reclassifying the bison's legal protection status, managing herd health and population growth, regulating growth through sustainable harvest, and donating animals to ranches with suitable habitat so the species can keep expanding across northern Mexico.

For the N'dee/N'nee/Ndé Nation, whose ancestral territory spans the Chihuahuan Desert, the bison's return carries weight beyond ecology. Fundación Pro Cuatrociénegas describes the project as part of restoring a thousand-year relationship of balance between the Indigenous peoples of the region and the species. FMCN's conservation director, Ana Laura Barillas, said the goal now is watching this keystone species "advance into new territories and strengthen its ecological role in the region."