Rancho El Uno

Conserving grasslands and species through regenerative ranching and grassland restoration

The Project

The project's objective is to conserve the grasslands and species that inhabit Rancho El Uno (ReU) through regenerative cattle ranching, low-stress bison handling, and grassland restoration.


ReU has operated as a nature reserve for the conservation of Chihuahuan desert grasslands for the past 15 years; it encompasses 18,546 hectares in the heart of the Janos Biosphere Reserve. ReU represents one of the most important sites on the continent for migratory birds and emblematic species, such as the American bison, the black-tailed prairie dog, and the golden eagle. ReU is a key piece in maintaining the functionality of the binational biological corridor that connects the Great Plains in the United States with the Mexican highlands.

Thanks to a large multi-institutional effort in Mexico, progress has been made in the recovery of the American bison (Bison bison) in the wild. In 2009, 23 bison were reintroduced into ReU from conservation herds in South Dakota, USA, and in 2018, when ReU went into FMCN stewardship, the herd numbered 230 individuals; today, it is 290, which requires correct handling to maintain the health and viability of the bison population. In November 2019, 19 bison were moved from ReU to the plains of Coahuila, in the El Carmen Natural Reserve, within the Maderas del Carmen Protected Area, in a coordinated effort between the National Commission of Protected Areas (CONANP, acronym in Spanish), the General Directorate of Wildlife of the Ministry of the Environment and Natural Resources (SEMARNAT, acronym in Spanish), CEMEX, AES Mexico and FMCN.

ReU is operated and managed by the Cuenca de Los Ojos organization (CLO), which has spent the last 40 years on the restoration and protection of Mexican grasslands in northeastern Sonora, in addition to having extensive experience in regenerative ranch management; an example of this is the nine properties under its custody in northeastern Sonora. The collaboration between CLO and FMCN for the conservation of ReU is formalized through a donation contract that is renewed every year.

The lines of work that guide ReU actions are:

  1. Ecosystem functionality for wildlife representative of the native grasslands of the Chihuahuan Desert.
  2. Synergy with local and national stakeholders for more effective management.
  3. Financial sustainability for the conservation of ReU.

ReU represents one of the continent's most important sites for migratory birds and iconic species, such as the American bison, black-tailed prairie dog and golden eagle.


Cuenca Los Ojos (CLO), the partner in charge of the administration and management of ReU, has worked on the systematization of databases with information from the monitoring of different biological groups and climatic variables that allow us to know the conservation status of the property and take strategic actions for management.

The Cuenca Los Ojos team at ReU has been trained in regenerative cattle ranching and low-stress bison handling, which has resulted in a shift in bison grazing to more effective and less invasive management.

During the first half of 2023, the ReU maintained its commitment as a center for projects related to the conservation of the grassland and the characteristic fauna of this ecosystem. The CLO team analyzed data from pasture health monitoring conducted in 2022 and developed a grazing plan considering the key species on the ranch. During this period, the ReU continued to be a central training point for students of various levels, offering the opportunity for educational visits and professional internships, highlighting the signing of a collaboration agreement with the Universidad Tecnológica de la Tarahumara. Additionally, CLO staff were trained in best practices for ranch management and participated in the National Bison Association meeting, which allowed them to update their knowledge regarding managing this species. These new learnings are planned to be applied in the ReU in the near future, thus contributing to the continuous improvement of conservation and education activities.
Learn more about the project:



      • The Nature Conservancy México