Cities and biodiversity: Spatial efficiency of land use

While there is an increased focus on promoting eco-friendly cities, biologically important but dangerous wildlife creatures encroach into cities, which can cause human-wildlife conflicts. We examine how the encroachment of wildlife affects humans’ decisions to exterminate wildlife, the spatial patterns of conflicts, and the size of cities. We develop a theoretical model where animals optimize their food intake by spreading out in response to heterogeneous feeding grounds in cities, and humans choose their housing location and exterminate wildlife in response to the presence of wildlife. We characterize a Nash equilibrium of land competition in every location and then prove the existence and uniqueness of the spatial equilibrium. We solve the optimal and the equilibrium and obtain properties with respect to human population density, the densities of wildlife species, the level of countermeasures against wildlife, and human-wildlife conflicts at each location; the numbers of species; and the size of cities.