Body size correlates to many aspects of a species' natural history, such as life span, abundance, and dispersal capacity. However, contrasting trends have been reported for the relationship between body size and these ecological traits. We have marked and recaptured 539 individuals from 27 species of fruit-feeding butterflies to study how body size affect species abundances, dispersal, and detectability in a Neotropical savanna (Cerrado). Body size has shown to be an efficient predictor of abundance, however this association was not significant after phylogeny was taken into account. Moreover, body size has positively influenced the dispersal rate, distance, and individual detectability, indicating that larger butterflies have a greater proportion of dispersing individuals over longer distances, and were detected through longer periods, than their smaller relatives. Large butterflies demand more resources, which may be forcing them to disperse in search for better habitats. On the other hand, smaller species may be better able to survive in small patches, which is explained by their lower dispersal ability. Nevertheless, their lower dispersal ability, if not compensated by large population sizes, may threaten the small-bodied species inhabiting environments with intense deforestation rates, such as the Cerrado. Finally, our study highlights the importance to consider species evolutionary history in order to study complex trait-environment relationships.