Omphile Samapodisa

Last update: 1 June 2016

Title: Seasonal dynamics of wild and domestic herbivore concentration and effects of grass biomass in Chobe enclave, Botswana

This study presents the following research questions:

  •  What impact do human settlements, agricultural fields and livestock have on grassland structure, composition and biomass, and on wildlife habitats?
  • How a change in grassland structure and composition affects the distribution of wildlife populations?

OBJECTIVES

The main objective is to determine the influence of land use on vegetation and wildlife around the Chobe enclave.

The specific objectives of this study are to:

  1. Quantify differences in vegetation composition and structure with increasing distance from cattle posts
  2. Assess wildlife and livestock density and distribution in relation to the effects of cattle grazing on grassland composition, structure and biomass
  3. Assess the temporal pattern of land use change (increase of cattle-post and crop field densities) in relation to herbivore distribution.

The Chobe enclave is critical for wildlife and tourism in Botswana (Jones, 2002), but it is experiencing increases in human and livestock populations, with much potential for competition and conflict with wildlife. While it is clear that increasing livestock populations and associated settlements negatively affect wildlife populations (Fritz et al., 2006; Ogutu et al., 2009, 2011), livestock grazing can improve grassland quality by removing stem and dead leaf and stimulating higher quality regrowth (Odadi et al., 2011). At the same time, wildlife species differ in their abilities to forage effectively in short as opposed to taller grassland (Murray & Illius, 2000). Consequently, the change in grassland structure as livestock grazing pressure decreases with increasing distance from cattle posts has the potential to cause competition or facilitation of grazing between livestock and different wildlife species, leading to varying distributions of different wildlife species on grazing gradients around pastoral areas (Bhola et al., 2012).  There is therefore a critical need to initiate studies on the effect of land use change in the region on wildlife distribution and abundance and how this may be mitigated without negatively impacting on local communities outside protected areas (Estes et al., 2012). Moreover, direct effects of human disturbance, such as chasing away of wildlife from settlements and poaching, and effects of transport networks such as roads, have the potential to disrupt habitat selection by wildlife populations. Increases in cattle-post density may reduce heterogeneity of the rangeland and disrupt the ability of pastoralists, livestock, and wildlife to access resources that vary over time and space, especially during periods of resource scarcity (Hobbs et al., 2008; Fynn, 2012; Fynn et al., 2014). The interactive processes of human population growth, agricultural expansion and environmental change are occurring throughout the world. These processes often go unnoticed, because their impacts are slow but cumulative (Hobbs & Gordon, 2010). Selective species in both diet and habitat may be locally extirpated (Western et al., 2009; Kinnaird & O'brien, 2012) if environmental changes are not monitored. Therefore, this project seeks to investigate how wildlife and cattle interact with each other and the resources found in their shared environment in the Chobe enclave. 

Last update: 1 June 2016