Nocturnal activity is a key factor in the success of bats, along with several other ecological characteristics of the group. Studying the activity patterns of bats can help to understand ecological and behavioural aspects of bat assemblies, especially in the Neotropics, where the group presents high species richness. The activity patterns of five species of Neotropical bats, sampled in a Reserve in the Brazilian Northeastern Region, were analysed. A general trend emerged, with an activity peak in the first half of the nocturnal observation. The overlap of activity patterns in closely related species (Artibeus planirostris and A. lituratus) agrees with previous findings that the nocturnal activity peaks in frugivorous bats have not evolved to relieve competition. The present work provides the first whole-night activity data for Dermanura cinerea. The results demonstrate the importance of whole-night sampling studies; not only as an opportunity to assess different ecological and behavioural data but also to efficiently register the abundance and richness of the assembly.