Competition can generate different ecomorphological patterns resulting in trade-offs, considering that certain resources are better used than others. We investigated how three species of Boana share resources in Serra de Itabaiana National Park and how morphology and environment cause trade-offs in interactions. We hypothesized that the large body size of B. faber might favor coexistence, allowing niche segregation with the other, smaller species B. albomarginata and B. pombali. Data collection occurred in the dry season of 2019 through active search at 18:00–22:00. We obtained microhabitat data for the species, recorded morphometric measurements, and analyzed gastrointestinal contents. There is evidence of resource partitioning in vertical space, as the large species occurs at ground level while the smaller congeners are found on higher perches. We hypothesize that lower sites can better support the large B. faber at our study site. There are no differences in the trophic niche, as prey volumes did not differ among the three species. Nevertheless, the size factor rendered low niche overlaps between B. faber and B. albomarginata, which are the phylogenetically closest species. Moreover, the species consumed typical prey of certain height ranges and accessed different items with high energy or hydric value. We believe that the sampling period performed in the dry season provides important trade-offs between the species studied with body size and ecological factors being crucial in this.