A dynamic model to analyze the sustainability of extensive common-pasture-based livestock husbandry in Sahel

Semi-arid regions in the Sahel have faced increasing environmental pressure due to population growth and decreasing rainfall. Building on earlier research we develop a stochastic dynamic programming model that describes extensive, common-pasture-based livestock under stochastic and spatially varying weather. We extend previous research by allowing animals’ movements between two regions and allow decisions to be adjusted when new information about the weather arrives. Decision rules to sell and move animals under exogenous price, market and climate scenarios are investigated. Our numerical analysis demonstrates that in the absence of efficient feed markets and under unpredictable weather, transhumance can be a rational livestock management strategy. Increased frequency of extreme weather conditions, such as heavy drought or rainfall, can have cross-regional spillovers and larger impacts on livestock husbandry than gradual changes in the mean annual rainfall or temperature suggest. Hence, policies should aim at mitigating the negative consequences of extreme weather across regions