The puma, or mountain lion, is one of the few mammals that range literally throughout Mexico, Equally at home in the mountain pines, on the parched desert ranges, or in the steaming jungle, this remarkably adaptable animal has one essential requirement, and that is a good supply of deer. Although the puma does take other prey, the deer is its bread and butter. I know of no place in North America where puma thrive in the absence of deer. Since all parts of Mexico have one or another species of dee, this basic necessity of the puma is widely available, except where ethe deer themselves have been exterminated. Nevertheless, it is still remarkable that so large and specialized a carnivore is able to live in such a variety of habitats as occur in Mexico.

However, puma populations vary greatly in density. The highest populations seemingly occur in the pine-oak zone of northern Mexico. Two localities seemingly occur in the pine-oak zone of northern Mexico. Two localities were I have found pumas especially abundant are the Río Gavilán basin in northwestern Chihuahua and the Sierra del Carman in northern Coahuila. To the south, pumas are progressively fewer, perhaps because there are fewer deer, and in the tropics because there are other large cats as competitors.

The puma is a much more mobile animal than the jaguar. In hinting, males especially seem to follow long circuits that require a week or even two weeks to complete. Females unhampered by family cares likewise hunt over extensive areas. These individuals “beats” are not defended form other pumas in a territorial sense, for they often overlap. Young and Goldman (1946) cite abundant evidence of the wide range of individual pumas.

However, females with young—even well-grown yearlings that hunt with the mother—have much smaller home ranges, judging from my experience. In camps along the Río Gavilán and in the Sierra del Carmen were found signs of family groups hunting day after day in the same canyon or series of adjoining canyons. There was no evidence that these lions were making a circuit. Only occasionally did we find larger tracks, which we assumed to be those of males. The males appeared to be covering more country than the females.