Optimal Control of Locusts in Subsistence Farming Areas

Locust swarms hit subsistence-staple-crop-growing households at random and are not privately controllable. A regional aerial-spraying scheme that supports these households’ livelihood at the least cost is proposed. The properties of this scheme are analysed and two steady states are identified. The saddle one is socio-economically superior to the stable spiral. Simulations reveal that the respective stationary probability of a household’s crop being devoured by the swarm diminishes with the number of households, yield per household, staple crop’s replacement price and spraying efficacy, but rises with the spraying cost coefficient, locusts’ multiplication rate and public planner’s discount rate.