Diet of Didelphis aurita and Micoureus paraguayanus and the fruit availability in a semideciduous Atlantic forest in Southern Brazil

Abstract

This study analysed the effects of diets and resource partitioning among Didelphis aurita and Micoureus paraguayanus, and their relationships with food availability in a semideciduous Atlantic Forest of southern Brazil. Species were separated by sex, age and reproductive condition to compare with dietary data. The fruit availability in the area was quantified bimonthly through collection of fleshy fruits and flowers available on the ground of the study area. Individuals of D. aurita trapped in the canopy vs. those trapped on the ground, or even regarding age and sex classes, did not differ in regards to their diet composition. Animals studied were heterogeneous in relation to their diet composition, being significantly different from each other (p = 0.03). The largest diversity indexes observed for both species in faeces and in the environment occurred during the rainy season. Both species presented insects in their diets, but with natural tendency to consume fruits or vertebrates (D. aurita). Rhythms of fructification of Piper sp. correlated with consumption by D. aurita (rs = 0.90, p = 0.03) and not by M. paraguayanus (rs = 0.40, p = 0.60). There were tendencies where independent young and lactiferous females of D. aurita correlated to the peaks of fruit availability during the rainy season.Key words: mammals, Didelphidae, resource availability, vertical strata, food habit.