that the southern extent of the historic range of the bison included northern Mexico and adjoining areas in the United States. On 8 December 2009, the Janos Biosphere Reserve was officially created through a presidential decree by then-President Felipe Calderón and published in the Official Journal of the Federation. As of May 2017, there were 138 bison living at Janos. In 2020, 19 plains bisons were transported to Maderas del Carmen, and formed the second rewilded herd in Mexico. Ecology The total area of the reserve is , which includes of grassland, of pine-oak forests, of halophyte vegetation and of riparian areas. There are 383 species of fauna in the reserve, of which 79 are mammals, 257 aves, 34 reptiles and 13 amphibians. Notable animal species in the reserve include: the pronghorn (Antilocapra americana), North American porcupine (Erethizon dorsatum), green toad (Anaxyrus debilis), cougar (Puma concolor), burrowing owl (Athene cunicularia), golden eagle (Aquila chrysaetos) and American black bear (Ursus americanus). Notable plant species in the reserve include the cimarron walnut (Juglans major) and biznaga cabeza de viejo (Mammillaria senilis). In mountains of the reserve there are forests of quaking aspen (Populus tremuloides), which are rare in Mexico. See also Mexican Protected Natural Areas List of protected grasslands of North America References External links Birds of Janos field guide from Conabio Bison herds Protected areas of Chihuahua (state) Protected areas of the Chihuahuan Desert Biosphere reserves of Mexico Protected areas of the Sierra Madre Occidental Important Bird Areas of Mexico