PhD student

Gina Arena

Thesis topic: Assessing long-term vegetation change on natural rangelands in the Nama-Karoo – Grassland biome boundary. 

Supervisors: Prof M. Timm Hoffman (PCU), co-supervised by Dr Helga van der Merwe (SAEON, Arid Lands node) and Prof Tim O’Connor (SAEON, National Office)
Collaborating institutions: South African Environmental Observation Network (SAEON)
Office: Room 5.04, HW Pearson Building


MSc Ecology, Environment and Conservation (University of the Witwatersrand); BSc (Hons) Ecology, Environment and Conservation (University of the Witwatersrand)


I completed my undergraduate, Honours and Masters degrees in Ecology and Conservation at the University of Witwatersrand in Johannesburg. My thesis focused on the pollination ecology of an Endangered South African endemic species, Aloe peglerae. Thereafter, I took a two-year work abroad hiatus in America after graduating. I later returned to South Africa to pursue my career in ecology and conservation. I was accepted onto the DSI-NRF Internship programme in 2016 where I was placed at SAEON’s long-term ecological research facility, Tierberg, in Prince Albert in the Karoo. It was through spending time in the Karoo that I became very interested in and passionate about this environment and its’ people. After completing the internship, I began my PhD studies at the Plant Conservation Unit at UCT. I am investigating how the vegetation on natural rangelands spread across the Nama-Karoo-Grassland ecotone has changed under the long-term climatic and land use trends of the region.

Research interests:

My current research interests fall broadly within Karoo ecosystem dynamics, but my specialty is vegetation ecology. Side research interests include those of plant pollination services (Aloe), plant population and habitat dynamics.

Peer-reviewed publications:

  1. Arena G, Dean WRJ, Milton SJ (2020) Ant communities in two habitats in Succulent Karoo shrubland. African Entomology 28(1): 202–209.
  2. Arena G, van der Merwe H, Todd SW, Pauw MJ, Milton SJ, Dean WRJ, Henschel JR 2018. Reflections, applications and future directions of Long-Term Ecological Research at Tierberg. African Journal of Range & Forage Science 35(384): 257-265.
  3. Djukic I, Kepfer-Rojas S, Schmidt IK, Larsen KS, Beier C, Berg B, Verheyen K, Arena G et al. 2018. Early stage litter decomposition across biomes. Science of the Total Environment 626: 1-26:
  4. Arena G, Witkowski ETF, Symes CTS (2015) Growing on rocky ground: Microhabitat predictors for site occupancy of Aloe peglerae, an Endangered endemic species with a restricted range. South African Journal of Botany, 100: 174 – 182.
  5. Arena G, Symes CTS, Witkowski ETF (2013) The birds and the seeds: opportunistic avian nectarivores enhance reproduction in an endemic montane aloe. Plant Ecology, 214: 35–47.

Conference abstracts:

  1. Arena G, Van der Merwe H, Hoffman MT & O’Connor T (2019) Conference abstract: Grassland-shrubland shifts in the eastern Nama-Karoo - Grasslands ecotone. Grasslands Society of Southern Africa, 1-4 July, Upington, Northern Cape.
  2. Arena G, Hoffman MT, Van der Merwe H & O’Connor T (2018) Conference abstract: Long-term vegetation change in the Nama-Karoo - Grasslands ecotone. Arid Zone Ecology Forum, 16 - 18 October, Robertson, Western Cape.
  3. Arena G, Milton SJ, Dean WRJ (2017) Conference abstract: The population size structure of Aloe claviflora on the Wolwekraal Nature Reserve in the Prince Albert district. South African Journal of Botany, 109: 326. DOI: 10.1016/j.sajb.2017.01.025
  4. Arena G, Symes CTS, Witkowski ETF (2013) Conference abstract: Neighbourhood effects on reproductive success in the endangered montane Aloe peglerae. South African Journal of Botany, 86: 144. DOI: 10.1016/j.sajb.2013.02.026.

Popular articles and professional communications:

  1. Arena G (2019) Feedback on sponsored attendance to the GSSA 2019 Congress in Upington. Grassroots, Vol 19 (3), September 2019.
  2. Arena G 2018. Kraalaalwyn: an oasis in the drought. Veld & Flora March 2018.
  3. Arena G. 2017. Using history to understand how natural rangelands in the Eastern Cape have changed. SAEON online newsletter Aug 2017.