Geographic range of the endangered Mexican prairie dog (Cynomys mexicanus)

The Mexican prairie dog (Cynomys mexicanus) is an endangered species that i s endemic to the northeastern Mexico states of Coahuila, Nuevo Leon, and Sa n Luis Potosi. We provide descriptions of historical, recent, and current d istributions of this species by integrating available distributional inform ation from the Literature, museum records, and new field observations. We e stimate current, recent, and historical ranges as 478, 768, and 1,255 km(2) , respectively, indicating the Mexican prairie dog has lost 62% of its hist orical natural habitat as large and medium-size colonies have been fragment ed into numerous small isolated colonies. Seventy-four percent of the curre nt geographical range is in Nuevo Leon (354.7 km(2)), 24% in Coahuila (112. 5 km(2)), and 2% in San Luis Potosi (9.5 km(2)). We located 88 active and 6 inactive colonies. Active colonies are larger, less isolated, and better c onnected than inactive colonies. Size of active colonies is correlated with density of active burrows and an index of connectivity.