Lessons from the past: Reconstructing ecological baselines for the South African terrestrial megafauna using long-term biodiversity data
Dr Sophie Monsarrat1,2, Professor Graham Kerley2
1Center For Biodiversity Dynamics In A Changing World (BIOCHANGE), Department Of Bioscience, Aarhus University, Aarhus, Denmark, 2Centre for African Conservation Ecology, Nelson Mandela University, Port Elizabeth, South Africa
Humans have driven biodiversity loss and modified ecosystem structure for millennia. Using modern ecological data therefore has the risk of considerably affecting our understanding of ecological patterns of “natural” species distributions and of the dynamics and drivers of past extinctions. This bias ultimately narrows our perception of the options available for conservation and the potential for species’ recovery. By extending the timeline usually considered in ecology, long-term archives can provide unique new insights into extinction dynamics and changing species distribution through time and represent a unique opportunity to better inform regional environmental management. Here, we integrate fossil, historical and modern occurrence records of large mammals in Southern Africa from the Holocene to the present to reconstruct ecological baselines and extinction dynamics for a high-priority land mammal fauna. We highlight the importance of considering long-term archives to estimate species’ historical distribution and natural habitat requirements and evidence local extinctions and changes in community composition, consistent with a response to the demographic expansion of European colonists in South Africa. These results contribute to novel baselines for conservation and provide a strengthened evidence-base for understanding long-term faunal responses to human pressures. It also allows the “shifted baselines” around modern mammal distributions to be identified, providing an avenue for new analyses of large mammal biogeographic patterns in Southern Africa.
Biography:
Sophie Monsarrat is a postdoctoral fellow in the Department of Bioscience at Aarhus University, Denmark, previously based at the Centre for African Conservation Ecology at Nelson Mandela University, South Africa. Her research lies at the interface of biogeography, conservation and history, with a focus on the long-term impact of human activities on biodiversity patterns at large spatial scales. She recently joined the MegaPast2Future project, which aims at developing a solid, synthetic understanding of megafauna ecosystem ecology and its potential role in developing a sustainable, biodiverse future. She has a PhD from Montpellier University, France, where she studied the impact of human exploitation on the historical distribution and abundance of marine mammals.