My time at the Agricultural Research Council back in 2011 was definitely one of the most amazing experiences I’ve had in Africa. The knowledge of the dedicated people that work at this institute is immense and their willingness to share their bush-knowledge has been of great value to me. To date, I’m very grateful to Mike Peel, John Peel, Andre Jacobs, Lucas Manaka, Hennie de Beer and many others that made my fieldwork such a rich experience.
The study at the ARC, of which I was part for a very small period, is one of the longest running vegetation and wildlife studies in Africa. During my time at the range and forage institute unit, I gathered vegetation and wildlife data in the western section of Greater Kruger National Park (South Africa) and analysed 15 consecutive years of wildlife, vegetation and climatic data. I already knew most of the animal species in the area through my studies at the Nelson Mandela Metropolitan University in 2008 but I didn’t know much about the vegetation in this specific area. This all changed because of the knowledge and patience of the field technicians who taught me very much about the flora of the lowveld area.
Next to being an essential part of my M Sc. Forest and Nature Conservation, the study also resulted in a poster presentation at a conference in New York City (USA), two presentations at the Annual Savanna Science Network Meeting in Skukuza, South Africa, and a publication at the European Journal of Wildlife Research. Interested individuals can read the abstract of my thesis below:
Elephants can change the vegetation structure in savanna ecosystems, especially when elephant densities are high. Elephants can thereby affect the herbivore assemblages in the areas they utilise. However, uncertainty remains regarding the consequences of these effects. Some researchers state that elephants compete with other herbivores, while others believe that elephants facilitate them. This study focussed on the cascading effects of elephants on the ungulate browser and grazer community in savanna ecosystems in South Africa. This was done by analysing 16 years of continued vegetation and game count data from three reserves adjacent to the Kruger National Park. The research showed that browse availability at feeding heights below 2 m decreased in areas with high elephant densities. All reserves, even those where browse availability below 2 m did not decline, showed a proportional shift towards more grazers in the herbivore community in the presence of elephants, moreover, the total biomass of mesobrowsers declined in reserves where elephant densities were high. The results indicate that an optimal elephant density appears to be valid for the granite lowveld savanna. Low elephant densities appear to benefit mesobrowsers in the herbivore community, whereas high elephant densities might lead to a megagrazer dominated herbivore community. Ultimately, an intermediate elephant density seems preferential for the overall herbivore community in the study area.
You can download the full article from Springerlink