A Dissertation submitted to the Faculty of Science in fulfilment of the requirements
for the degree:
Master of Science
In
School of Animal, Plants and Environmental Sciences,
University of Witwatersrand
Johannesburg
2015 / This study aimed to determine the role and relative importance of predator avoidance and
nutrition as processes influencing herbivore utilisation of burnt areas, at Satara, Kruger
National Park by using variation in fire size and fire season. The driving factors investigated
included forage quality, forage quantity, vegetation structure and predation risk.
The effect of fire size and season on the landscape was tested by recording grass height,
greenness, grass nutrient sampling and visibility. Results showed that fire size and season
had a significant impact on the physical environment by decreasing grass/forage quantity
post-fire but increasing grass/forage quality. Over time the plots returned to near pre-fire
conditions, with forage quantity increasing (grass height and biomass) and forage quality
decreasing (nitrogen availability). Visibility increased immediately post-fire, more significantly
in regards to herbivores with their heads in a “head-down/grazing” position than in a “head
raised/vigilant” position. As with forage quantity and quality, visibility returned to near pre-fire
conditions at the end of the study sampling period. The response of animals to these
changes in the environment was recorded through dung counts, camera traps and
behavioural observations. I found that there was increased use of burnt plots post-fire
through comparing herbivore presence on plots burned in different sizes and seasons,
day/night utilisation of plots, and using behaviour data I could determine to what extent
forage and predation risk were driving the use of burnt areas. I focused on three herbivore
species (Aepyceros melampus, Connochaetes taurinus and Equus quagga) which varied in
terms of body size digestive systems, forage type, and social behaviour. As expected, I
found that predation risk did appear to be more important in driving the behaviour of the
smaller-bodied herbivores but both nutrient requirements and susceptibility to predation were
shown to play a role in explaining the use of burnt areas for all three herbivore species.
Variation between plots in environmental factors such as tree density, forb percentage and
distance to water, were found to be not significant and thus did not confound our results
| Identifer | oai:union.ndltd.org:netd.ac.za/oai:union.ndltd.org:wits/oai:wiredspace.wits.ac.za:10539/20379 |
| Date | 11 May 2016 |
| Creators | Luhdo, Zoe |
| Source Sets | South African National ETD Portal |
| Language | English |
| Detected Language | English |
| Type | Thesis |
| Format | application/pdf, application/pdf, application/pdf, application/pdf, application/pdf |
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