Knowledge of habitat use and selection is essential to managing ungulate populations. This study assesses habitat use by elephant (Loxodonta Africana), giraffe (Giraffa camelopardalis), kudu (Tragelaphus strepsiceros), nyala (Tragelaphus angasii) and impala (Aepyceros melampus) in Thanda Private Game Reserve, KwaZulu-Natal. Firstly, I examine the effects of body size dimorphism, sexual segregation and predation on habitat selection and resource partitioning by ungulates. The mechanisms driving resource partitioning strategies were studied at three environmental scales, namely broader habitat (using habitat preference ratios), local environment (using Multi-Dimensional Scaling (MDS) and Analysis of Similarity (ANOSIM)) and plant (feeding heights using Analysis of Variance (ANOVA) and Regression analyses). At the habitat level, ungulates show distinct habitat preferences, independent of body size, which did not overlap, thus promote resource partitioning. Habitat selection, at the local environment level, varied among species but not between sexes. Therefore, body size class may influence selection for particular environmental characteristics. At the plant level, resource partitioning was evident among the larger species (giraffe and elephant) versus the smaller species (nyala and impala), but there was no apparent segregation among the sexes within species. Therefore, resource partitioning was strongest at the habitat level, bit less noticeable at the intermediate and finer plant scale. Secondly, I assessed the antipredator behaviour of multi-species assemblage in an experimental context (before vs. after lion reintroduction). I examined herbivore responses in terms of aggregation (forming safer groups), predator avoidance (selecting areas that predators avoid), and habitat selection in terms of habitat structure (selecting areas where capture is less likely), in response to lion reintroduction. Ungulates shifted habitats to avoid lion presence, i.e. into habitats least preferred by lion, and dominant species (based on body size) forced subordinate species into suboptimal habitats. However, counter predictions, ungulates did not increase their group size after lion were released. With the development of small private game reserves, intensive management is essential to maintain ecological heterogeneity, in this case through trophic cascades which promote coexistence. Managing ungulates as ecologically different according to body size will accommodate differences among herbivore populations. Long-term studies of habitat use by ungulates and predators will provide management with information to manipulate factors affecting habitat selection and predation, and thus sustainability of ungulate populations. / Thesis (M.Sc.)-University of KwaZulu-Natal, Westville, 2008.
Identifer | oai:union.ndltd.org:netd.ac.za/oai:union.ndltd.org:ukzn/oai:http://researchspace.ukzn.ac.za:10413/497 |
Date | January 2008 |
Creators | Canter, Kirsten. |
Contributors | Mackey, Robin. |
Source Sets | South African National ETD Portal |
Language | en_ZA |
Detected Language | English |
Type | Thesis |
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