Tropical rain forests have experienced extensive human exploitation—e.g., timber extraction, agricultural and residential development, wildfire—over the last century. Yet, rain forests can recover, and the emerging secondary forests today represent more than 30% of all neotropical rain forests. Their succession is marked by increases in biomass and species richness, which are affected by predator-prey interactions. Top-down control of plants by insect herbivores and their natural enemies (arthropods, birds, and mammals) has been shown to help maintain plant community composition in temperate forests. Although trophic cascades may strongly impact patterns of forest recovery and help explain their unpredictability, they are often overlooked in secondary succession.
I will investigate how predation of insect herbivores varies across a chronosequence of secondary succession in Panama using artificial plasticine caterpillars. This study will involve eight weeks of fieldwork at the Smithsonian Tropical Resource Institute (STRI) in Panama in ten forest sites of five different successional ages within the Barro Colorado National Monument and enhance our understanding of the effect of top-down control of insect herbivores on the recovery of tropical rain forests.