Few studies have evaluated changes in animal communities through the succesional process in tropical forests. Due to their role in seed dispersal and pollination, structural changes in the community of phyllostomid bats have direct consequences on forest regeneration and ecological succession. The objective of this work was to document changes in the structure of bat assemblages among secondary successional stages in a tropical rain forest in Chiapas, Mexico. The community of bats was mist-netted at ground level (n = 5 nets; 12 x 3 m ; 4 hrs/night) during 2 years in 10 sites belonging to 5 different successional stages. Two sites were used for each treatment: recently abandoned (2-4 years), 6-8 years of abandonment, 10-12 years of abandonment, 18-20 years of abandonment and mature forest.  

Results/Conclusions Total capture effort was 56 nights. We captured 878 bats representing 32 species belonging to the families Emballonuridae, Mormoopidae, Phyllostomidae and Vespertilionidae. Mature forest showed highest species richness and evenness, and possessed nine species that were exclusively found in this treatment. In contrast, the youngest treatment (2-4 years of abandonment) did not present any exclusive species, and showed the lowest species richness. Frugivores made up more than 90% of the species captured in all treatments with the exception of the mature forest where they occupied 83% of the sample. The lowest and highest similarity of species with respect to the mature forest was found with the 2-4 yr-old treatment and the 18-20 yr-old treatment (classic Jaccard = 0.27 and 0.44, respectively). Species diversity did not differ significantly among treatments of different succesional states but all were lower compared to mature forest. We conclude that the continuous forest is the main reservoir of species richness; however, fragments of secondary vegetation also possess a great diversity of species, especially in the frugivore and nectarivore guilds.