We Welcome the First Bison Conceived at El Uno!

We worked with several partners in this project:

•  The National Parks Service
•  The Wind Cave National Park in South Dakota
•  The Mexican National Protected Areas Commission (CONANP)
•  The National Ecology Institute of the Mexican National Autonomous University (UNAM)
•  The Chihuahua Autonomous University
•  The Municipality of Janos
•  The Chihuahua State Government
•  The Tutuaca Mountain School

On May 11, sometime around 5:30 PM, all of The Nature Conservancy staff at El Uno Ecological Reserve (Janos Valley, Chihuahua, Mexico), rejoiced with the birth of a female bison calf. This is the first calf conceived locally since 2009, when the Conservancy and a national working group consisting of government agencies, universities and NGOs, initiated the began the Bison Reintroduction project.

The first bison calf conceived in Mexico is a girl!

The first bison calf born at El Uno on May 13, 2010, was conceived in the U.S.

“This new calf was conceived in El Uno, Mexico. We are very happy!” says Antonio Esquer, who manages our conservation work in the Janos Grasslands.

From Canada to Mexico, grasslands are relatively similar. There are only a few differences, such as the temperature in summer, the amount of snow in winter, and their native vegetation. That is why the bison herd in El Uno—coming all the way from South Dakota—has been able to adapt very well to the grasslands at the Janos Biosphere Reserve.

“The apparent reproductive success of these season—we expect more than 10 births—can be interpreted as proof of the good adaptation of the herd, and of the efforts to provide the bison with the best of care: good sanitation, balanced diet with special supplements for better results, a good water supply, and regular vet check-ups”, Esquer explains.

23 bison were reintroduced at El Uno Ecological Reserve in November of 2009, a donation of the Wind Cave National Park, South Dakota. This effort was part of a cooperation agreement between the National Parks Service and the Mexican National Protected Areas Commission (CONANP). The Nature Conservancy is playing a key role in the national Bison Recovery project by safeguarding and managing the herd at its 45,000 acre El Uno ranch.

Bison reintroduction is important for the recovery of the Chihuahuan Desert grasslands and it is one of the Conservancy’s most important projects in Mexico. They help to break the soil so that seeds can grow—they also help spread these seeds—in turn allowing for improved water filtration and thus better recharge of the aquifers. Bison also keep the grass short in certain areas, which is essential to the prairie dog and other species vital to the grassland ecosystem.

“This birth is a success story because our goal is to ensure new bison are born to repopulate their original range in Mexico. That is why we take good care of them and why we feel so proud!” Esquer says.


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