Past and current graduate students

Twané Bester, MSc (cum laude)

University of Pretoria (2020-2022), co-advisor: Prof. Adrian Shrader

Thesis: “Exploring the influence that monoterpenes have on the dietary choices of elephants”

My research interests persist of the factors that modulate plant-herbivore interactions. In particular, I focus on the utilization of plant secondary metabolites as chemical defenses against herbivory, the way in which odoriferous secondary metabolites shape the olfactory landscape of herbivores, and the influences that the volatile organic compounds, monoterpenes, have on the olfactory-driven dietary choices of megaherbivores.

For my thesis, I explored how African elephants (Loxodonta Africana) use olfactory cues to make foraging decisions. One type of volatile plant secondary compounds, that influence these decisions, are monoterpenes. Little is known about how individual monoterpenes, or their mixtures, influence elephant dietary choice. I found that deterrence is influenced by monoterpene concentration and whether the monoterpenes are presented in mixtures. I also found that different individual monoterpenes have the potential to influence elephant dietary choice to varying degrees.

Carys Corry-Roberts, MSc candidate

Rhodes University (2021-present), co-advisor: Prof. Dan Parker

Thesis: “Impacts of anthropogenic disturbances on savanna vegetation dynamics and tri-trophic relationships”

My research interests are broad, but include spatial ecology of threatened and endangered species, behavior of large mammals and their response to anthropogenic pressures, the effects of habitat restoration on biodiversity, and mediating human-wildlife conflict.

For my MSc, I am exploring how herbivores respond to habitat management practices and predation risk. Habitat use and the behaviors of herbivores are influenced by the trade-off that exists between risk of predation and food quality and availability. African savannas pose a particularly interesting trade-off for herbivores, not only because they host a high diversity of predators and prey species, but also because savannas exist in a constant flux of vegetation structure. Both local and global drivers are driving savannas to become more tree-dominated, which often requires habitat management intervention. The broad aim of my research is to understand how anthropogenic disturbances that influence vegetation dynamics can alter tri-trophic relationships in African savannas. I am specifically interested in understanding 1) how various burning and mowing management practices influence large mammal habitat use, 2) the environmental drivers of antipredator responses of herbivores across the landscape, and 3) how herbivores forage under competition.

Lindokhule Gumede, MSc candidate

University of Mpumalanga(2022-present), co-advisor: Prof. Dan Parker

Thesis: “Seasonal drivers of insectivorous bat activity: exploring the relative importance of food abundance, vegetation structure, and water availability”

My Master’s project focuses on the drivers of insectivorous bat community structure in a southern African savanna. My study will use acoustic monitoring of bat communities near the Kruger National Park to better understand the impact of important ecological drivers on their community structure and composition. I am be investigating the relative importance of vegetation structure, water availability, and insect abundance on bat activity and community assemblage.

Christoffel de Lange, MSc candidate

University of Pretoria (2021-present), co-advisor: Prof. Adrian Shrader

Thesis: “Spatial variation in vigilance behaviours and its effect on food intake rates”

Early predator detection is one of the key ways in which prey reduce their vulnerability to predation. Animals therefore frequently allocate time towards anti-predator vigilance. Being vigilant, however, comes at a cost because it disrupts the time spent searching for and handling food, thereby reducing food intake rates. To meet conflicting demands for food and safety, prey must assess the risk of predation and select vigilance strategies that balance them. The major goals of my thesis are to assess various vigilance strategies that are employed by wild herbivores in different habitats that vary in predation risk and food availability.