Range extension of the opossum (Didelphis virginiana) in the Chihuahuan Desert of Mexico

摘要

The Virginia opossum (Didelphis virginiana) has a geographical distribution that ranges from southern Canada to northeastern Costa Rica, including large portions of the United States and Mexico (Gardner, 1973; Hall, 1981; Gardner, 1982, 1999). During the last century D. virginiana has extended its geographical distribution to the north and west (McManus, 1974), due to occasional introductions, both planned and accidental. In thct, populations of this species in the United States and Canada to the west of the Great Plains and the Rocky Mountains were introduced from populations in the eastern United States (Gardner, 1982). In general, it is considered that the Great Plains of Canada and the United States, together with the desert zones of New Mexico and northeastern Mexico constitute a barrier for this species (Hall, 1981). Here we report the third record of D. virginiana from the State of Chihuahua, at a site 235 km northeast from Carimechi and Batopilas where it previously had been recorded within this state.