Elementor #11478
Serengeti's
Wildebeest and Zebra
Migratory movements
What is the extent of the wildebeest and zebra migration?
The digestive differences between ruminants and hindgut fermenters mean that zebra have less restricted foraging requirements than wildebeest and, therefore, the seasonal movements of zebra tend to be more diffuse. The patterns of wet season and dry season of zebra and wildebeest are different from each other as illustrated.
The seasonal distribution of wildebeest and zebra suggests that the zebra movement tends to be more diffuse than wildebeest. Wildebeest are constrained by food requirements and move in a coherent triangular pattern around the ecosystem. Zebra gain sufficient energy from lower quality grass provided there is sufficient biomass and move in dispersed linear north- south patterns.
It was not until the population exceeded about 750,000 animals that the wildebeest migrated in a more cohesive fashion using the full extent of the Serengeti ecosystem.
During the dry season the movement is less than 4km per day because food and water are accessible only in local areas around the Mara River. The daily movement of zebra shows a similar trend to wilde- beest, however with much less variance
Both species tend to move less during the dry season when resources are scare. During the wet season when both zebra and wildebeest are on the short grass plains, they tend to move further each day probably because the grazing conditions change very quickly due to fast greening and drying process associated with the shallow soils.
These long movements are somewhat counter-intuitive as one might expect less movement during the wet season when resources are plentiful. However, the localized rain showers and shallow soils on the short grass plains result in fast greening and drying processes and, combined with the high energy requirements of lactating females, most likely accounts for large daily movements of wildebeest during the wet season.