Utilization of woody browse and habitat by the black rhino (Diceros bicornis) in western Itala Game Reserve

Abstract

Black rhinoceros browse utilization was assessed at the woody plant species and community levels in western Itala Game Reserve, South Africa, using a semi-quantitative, plant-based method. These knowledge was used to hypothesize the possible effects of vegetation change on the black rhinoceros (Diceros bicornis). Acacia nilotica, Acacia karroo, and Dichrostachys cinerea contributed most to the diet, and Cassine transvaalensis, Rhus guenzii, and the Acacia gerrardii were the most preferred species. Eighty-six percent of the recorded browse was from plants <2.5m, suggesting that a change from open woodland, with many trees, to a closed woodland, with a few small trees, would disadvantage black rhino. Plant communities ranged from highly utilized (bottomland scrub forest) to unutilized (Combretum apiculatum sparse woodland). The extremely patchy distribution of browse utilization within communities suggests that there are other important factors affecting browse utilization besides plant species composition. It appears that tall grass detracts from browse value, while factors that improve access, such as gentle slopes and paths, enhance habitat suitability. It is hypothesized that forest verges provide important black rhino feeding areas.

Keywords: Black rhinoceros; botany; Browsing variability; Diceros bicornis; distribution; Food species; habitat; Habitat preference; Itala Game Reserve; karoo; south africa; species composition; utilization; vegetation change; Woody plant speciesbr>
African Journal of Range & Forage Science, Vol. 10, Iss 1, p 36-40