Darwin’s fox is omnivorous and highly opportunistic, having a broad diet including a variety of small mammals, birds, reptiles, amphibians, beetles, invertebrates, fruits, berries and seeds (2) (4). This variable diet is important for the fox’s survival as the availability of food items changes with the seasons within its highly fluctuating environment. Although hunting is ordinarily performed alone, up to four individuals may concentrate around a carcass for a few days. On Chiloé, these foxes also sometimes kill poultry and raid garbage dumps, and even enter houses at night in search of food, apparently unafraid of the people and dogs within (2).
Whereas this species is primarily solitary on Chiloé, except during the breeding season when temporary pairs form, pairs appear to persist throughout the year on the mainland. These pairs have been known to share their home range with offspring from previous years, with all family members associating closely with one another. Litter size is estimated to be two to three pups (2).