Flood-stimulated herbivory drives range retraction of a plant ecosystem

Climate change is generating extreme climate events, affecting ecosystem integrity and function directly through increases in abiotic stress and disturbance and indirectly through changes in the strength of biotic interactions. As consumers play an essential role in ecosystem functioning and have been shown to be highly sensitive to climate conditions, improved understanding of their role under changing environmental conditions is necessary to accurately anticipate climate change impacts on ecosystem integrity. We evaluated if prolonged heavy rains, a climatic event increasing in severity in many places around the world and coincident increases in coastal flooding duration intensify consumer control of foundational saltmarsh grass structure and quantify the consequences of flooding-consumer interactions on saltmarsh range extent. To achieve this, we analyzed: historic trends in crab grazing; crab numbers and activity in and out of rainy years on the low marsh edge; vegetation retreat fr...