Diet Of The Gracile Mouse Opossum (gracilinanus Microtarsus) (didelphimorphia: Didelphidae) In A Brazilian Cerrado: Patterns Of Food Consumption And Intrapopulation Variation

The diet of the gracile mouse opossum Gracilinanus microtarsus was studied in a cerrado remnant in south-eastern Brazil through the analysis of faeces sampled from adult individuals. Patterns of food resource consumption were assessed using the statistics of per cent occurrence. Intrapopulation variation in the number of food items detected in faeces as a function of relevant factors was inferred using generalized linear models. The latter statistical formalism also allowed variation in the number of food items detected in faeces to be interpreted in terms of rate ratios among levels of significant factors. Insects, spiders, snails and fruits were detected in the faeces of G. microtarsus, with insects, particularly termites, beetles and ants, being the most frequently detected food resource. These food resources were consumed in proportion to their relative abundance in the cerrado, suggesting that G. microtarsus is an opportunistic forager feeding primarily on insects. 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