Canopy herbivory and succession in a Brazilian tropical seasonally dry forest

The general pattern of herbivory throughout succession has been drawn chiefly from temperate forest studies and mainly at the understorey. This is one of the very few studies to document canopy herbivory in relation to successional stages of tropical seasonally dry forests. Diversity of free-feeding herbivores (chewing and sap-sucking) and leaf damage caused by insect guilds (folivores, leaf miners and galling insects) were quantified in the canopy of 117 trees distributed in three areas of intermediate stages and three of late stage of succession of a tropical seasonally dry forest, in Serra do Cipo, Minas Gerais, Brazil. The richness of the chewing and sap-sucking guilds of herbivores was higher in late succession stages. The abundance of sap-sucking herbivores was also higher in the late stage, whereas chewing insects were more abundant in the intermediate succession. Overall leaf damage was higher in the earlier stage of succession. Folivory was the most frequent type of leaf damage in both succession stages and was present in 92.33% of the leaves, followed by leaf mining in 14.58% of the leaves, and galls in 5.27% of the leaves. Folivory showed no difference between successional stages, while leaf miners and gallers showed higher frequencies in the intermediate stage. These results largely corroborate the pattern earlier documented for temperate forests, of increasing diversity of herbivores and decreasing leaf damage across succession. More specific studies in tropical forests, however, did not corroborate the pattern found in temperate regions. The present study emphasises the importance of sampling across canopy of multiple plant species and analysing herbivore guilds individually for better understanding herbivory in tropical dry forests.