Overabundant native herbivore impacts on native plant communities in south-eastern Australia

Abstract

Native herbivores can affect the structure and function of plant communities. Most studies of overabundant native herbivore effects on native plant communities in south-eastern Australia are observational or compare, at most, two levels of herbivory (ambient vs. none), and typically do not separate out the impacts of multiple herbivores. Several studies show that high densities of herbivores had mostly negative effects on plant regeneration and growth. These effects were usually attributed to palatability differences amongst plant species. Surprisingly, few studies have quantified vegetation responses across a gradient of herbivore density, and impacts on plant communities (i.e. species richness, composition, beta diversity) have not been well studied. Hence, there remains a need to better understand how native herbivores impact plant communities at different densities.