ECOLOGY OF MEXICAN PRAIRIE DOGS, CYNOMYS-MEXICANUS, IN EL MANANTIAL, NORTHEASTERN MEXICO

The Mexican prairie dog (Cynomys mexicanus) is an endangered species that is endemic to northeastern Mexico. To obtain basic data on diet, parasites, reproduction, relationship with other small mammals, and predators, during the spring and summer, we studied a prairie dog colony at El Manantial, San Luis Potosi, northeastern Mexico. Mexican prairie dogs preferentially fed on grasses in the spring, hut as grasses matured, prairie dogs changed to a diet principally composed of forbs. Prairie dogs exhibited low levels of parasitism. Breeding peaked from mid-January to early February, but extended, at low levels, into early April. Nocturnal rodents and lagomorphs were more abundant and had a higher species richness on an abandoned prairie dog colony than on the active one, except for grasshopper mice (Onychomys arenarius), which were less abundant on the abandoned colony site. Coyotes (Canis latrans) appeared to be the most important predators of prairie dogs.