Natural Diet at a Restinga Forest and Laboratory Food Preferences of the Opossum Philander frenata in Brazil

The diet of the marsupial Philander frenata (Didelphimorphia, Didelphidae) at Restinga de Barra de Maricá, Rio de Janeiro state, Brazil, was analyzed in 180 faecal samples collected in 29 months from 1986 to 1990, and by food preferences in the laboratory. In the faeces remnants mainly of invertebrates, besides fruits and vertebrates were found, and diet comparisons were made between sexes, ages and seasons of different humidity. Laboratory experiments corroborated the field data. No significant difference in diet was found between sexes. Although field data showed that subadults and adults eat more vertebrates than young, in the laboratory all animals irrespective of their age showed the same food preference. Invertebrates were more consumed in humid than in superhumid months. Vertebrates were taken opportunistically. There was an inverse relationship between eating of fruits and available water in the environment. Fruits are probably water complements in dry months, as these marsupials have difficulties in maintaining water balance without access to drinking water.