Emergent Effects of Multiple Natural Enemies
Speaker: Tom Cameron (University of Leeds)
Species exist in a web of interactions with other species. Despite this, population and evolutionary ecology has typically studied pairs of interacting consumer-resource organisms (e.g. predator-prey, parasitoid/parasite/pathogen-host). While the study of pairs of interacting species has led to many modern theories and applications of consumer-resource ecology, recent reports have highlighted the importance of studying the effects of multiple interacting species as they reveal novel and unanticipated dynamics. Here I report on single, 2- and 3-species communities and show effects of an insect predator and an insect pathogen on population size, dynamics, cycle period and variance of a shared prey population. Furthermore I demonstrate that in line with a recently published model of insect outbreaks, the period of time within and between peaks in prey abundance are determined by switches in the relative importance of interactions of the generalist predator, the specialist pathogen and the environment of their shared prey population.