Neither large nor small: intermediate-sized food items for the cubs of the Patagonian gray fox (Pseudoalopex griseus)

According to central place foraging theory, adult Patagonian gray foxes (Pseudoalopex griseus) behaving efficiently should consume on the spot those food items too large to be carried and those too small to warrant being carried to the den. Consequently, fox cubs should be provisioned with intermediate-sized items. We tested this prediction by analyzing 96 fecal samples from adult foxes and 82 fecal samples from cubs belonging to three different dens collected near Junín de los Andes in the province of Neuquén, Argentina, from November 1994 to January 1995. As predicted, adult foxes consumed carrion of large ungulates (large items) and arthropods and berries (small items) significantly more often than cubs did. Cubs ate more intermediate-sized vertebrates, from lizards and birds to rodents and hares. Medium-sized armadillos, which are difficult to handle and transport, were consumed only by adults. Cubs ate some insects, which were probably captured by the cubs themselves near the den.Peer reviewe