Resource utilization by large migratory herbivores of the Athi-Kapiti ecosystem

Abstract

The goal of the study was to establish whether the changes in land use affect resource utilization by large migratory herbivores in the Athi-Kapiti ecosystem. Athi-Kapiti ecosystem comprises Nairobi National Park and the Athi-Kapiti plains (community livestock grazing grounds). Land use information was obtained from existing literature. Pin frame technique and harvest method were used for plant biomass sampling, while road and foot counts were conducted for migratory large herbivores and livestock within the ecosystem, from November 2003 to May 2004. Emphasis was given to the wildebeest (Connechaetes taurinus), zebra (Equus burchelli) and cattle. Results show that green plant biomass available in the park was significantly different from that on Athi-Kapiti plains [Wilcoxon (two-tailed), P < 0.05]. Further analysis showed significant seasonal differences in the park [T test (two-tailed), P < 0.05]. In the community grazing area, significant monthly and seasonal variations in plant biomass were evident (one way ANOVA, P < 0.05). In summary, more wildebeest were observed on Athi-Kapiti plains than in the park. The zebra showed monthly variations within the whole ecosystem, resulting in a distinct movement pattern. Plant biomass varied depending on the rainfall, which in turn influenced the movement of migratory herbivores within the ecosystem.