Janos Biosphere Reserve is a protected area located in northwestern Chihuahua, Mexico. The northernmost portion of the reserve is adjacent to the border with New Mexico. The reserve was established in 2009 and covers 526,482 hectares of predominantly shortgrass prairie and temperate forests. The reserve is located in the Janos valley within the Chihuahuan desert, and it’s the first of its kind in Mexico to focus on the protection of grasslands. Grasslands are one of the most endangered ecosystems worldwide since most have been converted to agricultural lands and what remains continues to be modified or affected by human development. North American prairies once extended from southern Canada all the way to northern Mexico and it is estimated that before European settlement between 30-60 million bison roamed the prairies along with pronghorn and other iconic species such as wolves and grizzlies.
Wherever prairie ecosystems remain in good condition they boast incredible biodiversity and such is the case in Janos where the second largest black-tailed prairie dog complex in North America can be found, as well as the largest population of golden eagles in Mexico, and the only wild bison population in Mexico. More than 250 species of plants have been recorded as well as more than 380 species of animals. Some of the species that can be found include burrowing owls in prairie dog colonies, thick-billed parrots in the forested mountains, and a great diversity of snakes and lizards throughout the reserve. Grizzlies, wolves, bison, and most pronghorn gradually disappeared with the arrival of European settlement and the conversion of the land into agricultural fields and cattle ranches. In 2009, a small herd of bison was reintroduced at the Nature Conservancy’s Rancho El Uno, and it was the first time in over a century that wild bison roamed Mexican prairies.
Another iconic species of the North American prairies whose current overall population is less than 2% of what it was over two centuries ago is the prairie dog. There are five species of prairie dogs in North America. Black-tailed prairie dogs occupy the most extensive range. Prairie dogs are social diurnal burrowing rodents that live in colonies that can extend for miles and can house thousands of individuals. Prairie dogs are considered a keystone species – they play a critical role in the structure and function of their ecosystem disproportionate to their abundance – thus, the collapse of prairie dog colonies leads to dramatic changes in overall species composition. A notable example of this is the near extinction in the wild of black footed ferrets which are completely dependent on prairie dogs for food and shelter. By the mid-1980’s only 18 black-footed ferrets remained in the wild in all of North America. Fortunately, tremendous effort has been carried out by different agencies and organizations and the species was brought back from the brink of extinction; although, their long-term survival is dependent on the protection and the long-term survival of prairie dogs. Black footed ferrets have been reintroduced in a handful of places including Janos Biosphere Reserve.
Many farmers and ranchers have been at war with prairie dogs for decades and millions have been poisoned throughout the North American prairies since they are perceived as foraging competitors, their burrows are perceived as potential hazards for cattle, and are considered voracious consumers of commercial crops. A more recent threat; yet, equally devastating to prairie dogs is the arrival of plague which is transmitted by fleas and completely wipes out entire colonies. The maligned image of prairies dogs by certain groups is unfounded since before the arrival of cattle, bison coexisted with prairie dogs for centuries, and it has been demonstrated that bison and pronghorn prefer to forage in prairie dog colonies due to a higher occurrence of highly nutritious plants.
Prairie dogs are a critical component to the health and biodiversity of prairie habitat since their digging aerates the soil; they prevent shrub encroachment; their burrows provide shelter and nesting habitat for species such as burrowing owls; and, prairie dogs are prey for many species not just black footed ferrets. Prairie dogs are not the only keystone species found in the reserve, kangaroo rats are also considered ecosystem engineers; although, their activities and burrows change the landscape in a different direction since the storage and germination of seeds inside the burrows leads to shrub growth.
The region where the reserve is located is not densely populated and consists of small communities of traditional ranchers, farmers, and Menonite communities. The human population within the municipality of Janos where the reserve is located was estimated to be just under 11,000 in 2010; nonetheless, the long term effect of human activities such as intensive agriculture is still a concern for the long term sustainability of the ecosystem and the regional economy. Some of the threats that could affect the reserve include groundwater depletion to support intensive agricultural practices, overgrazing, soil erosion, and desertification. Janos Biosphere Reserve is a relatively new protected area and as such there is still a lot of work that needs to be done – which seems to be underway – to find balance between conservation and wise management of natural resources so that human economic activities can continue to flourish for a long time alongside a healthy ecosystem.
Defenders of Wildlife
The Nature Conservancy
Universidad Nacional Autónoma de México – Instituto Nacional de Ecología