Diets of three sympatric Neotropical small cats: Food niche overlap and interspecies differences in prey consumption

Dietary investigations of sympatric felids are means for understanding how closely related species deal with food resources in a potentially competitive scenario. The diets of the oncilla Leopardus tigrinus, the jaguarundi Puma yagouaroundi and the ocelot Leopardus pardalis were studied through the analysis of scats in Araucaria Pine Forest with Natural Grasslands of southern Brazil. Small mammals comprised the bulk of the diets of the three felids, followed by birds and reptiles. The smallest food-niche overlap index was 0.84, indicating that these felids shared an important portion of their food resources. Inter-species differences were detected in the consumption of the most frequent rodent prey; L. tigrinus was the only species that consumed all the most frequent rodent prey differently from the rate expected from their abundances. Although these findings suggest competitive interactions, with the oncilla being the most subordinate species, further experimental investigations are necessary to elucidate more precisely how these syntopic felids coexist. The effects of sample size and its influences on the evaluation of the diets of the felids, especially of the ocelot, are discussed. We compare our data to a previous study in the same area, to account for the possible influences of biased sampling and uneven distribution of food resources on the diet of the ocelot. The opportunistic feeding behavior and the abundance of their primary prey (cricetid rodents) seem to allow these small cats to be resilient despite severe anthropogenic disturbance in the study area. We further suggest guidelines for future studies in the study region, in order to understand the dynamics of mammalian carnivores demography.