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

According to central place foraging theory, adult Patagonian gray foxes (Ps eudoalopex griseus) behaving efficiently should consume on the spot those f ood items too large to be carried and those too small to warrant being carr ied to the den. Consequently, fox cubs should be provisioned with intermedi ate-sized items. We tested this prediction by analyzing 96 fecal samples fr om adult foxes and 82 fecal samples from cubs belonging to three different dens collected near Junin de los Andes in the province of Neuquen, Argentin a, from November 1994 to January 1995. As predicted, adult foxes consumed c arrion of large ungulates (large items) and arthropods and berries (small i tems) significantly more often than cubs did. Cubs ate more intermediate-si zed 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.