Land Subdivision, Heterogeneity, and Declining Food Security for African Pastoralists

Pastoral livestock inhabit landscapes that are spatially heterogeneous and have forage patches that pulse in their value to animals. Mobile pastoralists have evolved movement patterns to maximize use of these ephemeral food sources. In pastoral communities across Africa, changes in land tenure policy and socioeconomic pressures have caused pastoralists to decrease their mobility. Pastoralists recognize that shrinking access to land reduces their options to find forage, and theory suggests that the capacity of land to support herbivores decreases as a power of the square root of area accessible. We used ecosystem modelling in South Africa and Kenya to quantify declines in the number of livestock that can be supported under subdivision