- Title
- The role of elephants in Hluhluwe-iMfolozi Park: Perceived versus measured effects on woody vegetation
- Creator
- Mbongwa, Siphesihle
- Subject
- Woody plants -- Environmental aspects
- Date Issued
- 2020
- Date
- 2020
- Type
- Thesis
- Type
- Masters
- Type
- MSc
- Identifier
- http://hdl.handle.net/10948/48467
- Identifier
- vital:40879
- Description
- Elephants were successfully reintroduced into the 900 km2 fenced Hluhluwe-iMfolozi Park (HiP) from 1981 onwards and their population has increased exponentially since. Their initial reintroduction was motivated by the need to control bush encroachment and to maintain ecosystems such as grassland and open woodland, and to restore ecological processes offered by elephants. The subject of the HiP elephant population and their impact on vegetation in the Park has become controversial; with some concerns being raised that the population is too high and is negatively affecting the vegetation. An absence of a vegetation monitoring programme in protected areas with elephants creates uncertainty leading to an ‗elephant impact‘ debate. This study aimed to compare the perceptions of stakeholders regarding the issue of elephant impact in HiP with measured elephant impact on the vegetation in the Park. The perceptions and concerns of stakeholders regarding the effects of elephants on vegetation in HiP were investigated using a questionnaire. Stakeholders reported that elephants and fire were the main factors shaping vegetation change in HiP over the past decade. Sclerocarya birrea, Senegalia burkei and Schotia brachypetala were reported as the most negatively affected species. Also reported that they are concerned about the effects of elephants on the number of tall trees in the park, tree mortality and elephant‘s effect on rare indigenous vegetation. Most interestingly, the results showed that the groups of stakeholders had different perceptions of the level of elephant impact on the vegetation in the park; except for researchers and tourists whose were not significantly different from each other. Managers had the most respondents that reported that the level of elephant impact is unacceptable, while most researchers and tourists reported that the level of elephant impact is at an acceptable level. Vegetation plots that had been surveyed in 1999, 2003 and 2007, were resurveyed in this study during 2017 to assess elephant impact on vegetation over time. Comparison between the years sampled showed that there was a decrease in the density of tall trees, while the density of trees in 0.5-2 and 2-4 m height classes increased over the same period. Elephants had a strong preference for utilizing tall trees (>4 m) and a strong avoidance for trees in the height range from 0.5-2m tall (Jacobs selection index 0.56 and -0.69, respectively). This trend was apparent for all sample periods. In addition, elephants also showed a strong preference for some rare species including S. brachypetala and Sideroxylon inerme. Between 1999 and 2017, the density of preferred species has decreased while the density of avoided species has increased. I conclude that elephants are having a noticeable impact on the vegetation at HiP by changing vegetation structure to a shrub dominated vegetation, and causing a shift in species composition towards avoided species. The findings of this study show that the perceptions of stakeholders on the effects of elephants and the level of elephant impact on vegetation match the results from measured elephant impact - vegetation survey. However, Thresholds of Potential Concern (TPCs) should be outlined in the elephant management plan and are required to determine whether the levels of elephant impact at HiP have exceeded an acceptable level or not. This study conforms to previous research that an uncontrolled elephant population can have substantial impacts in fenced reserves. This study shows the importance for long-term and continuous vegetation monitoring programme to obtain reliable data to determine trends in vegetation changes over time.
- Format
- vi, 101 leaves
- Format
- Publisher
- Nelson Mandela University
- Publisher
- Faculty of Science
- Language
- English
- Rights
- Nelson Mandela University
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NMU School of Environmental Sciences
| Thumbnail | File | Description | Size | Format | |||
|---|---|---|---|---|---|---|---|
| View Details Download | SOURCE1 | Mbongwa, S 218207026 Dissertation April 2020.pdf | 2 MB | Adobe Acrobat PDF | View Details Download |