Bison Return Revives Desert Ecosystem in Mexico’s Cuatrociénegas Reserve

American bison, extinct in Mexico for roughly 160 years, were reintroduced to the Chihuahuan Desert’s Cuatrociénegas reserve in Coahuila during 2025, with an initial trio followed by 44 additional animals—38 females and 6 males. The initiative, organized by Fundación Pro Cuatro Ciénegas in partnership with the Mexican Fund for the Conservation of Nature and the Museo del Desierto, targets the restoration of a landscape once degraded by overgrazing and erosion.

Gerardo Ruiz Smith, director of the foundation, describes the bison as ecosystem engineers whose grazing promotes plant diversity, whose hooves break crusts to aid water infiltration, and whose dung supports dung-beetle activity that enriches soil. Their presence has already attracted predators such as pumas and lynxes, while birds are using their fur for nesting, indicating a revitalizing food web. The project aligns with a national movement to reestablish keystone fauna, including Mexican wolves and Sonoran pronghorn, to heal fragile ecosystems across the country.