Simulation of host-parasite-landscape interactions: Influence of season and habitat on cattle fever tick (Boophilus sp) population dynamics

Integration of temporal and spatial factors controlling host-landscape interactions is essential to development of systems perspectives important to the management of animal parasites. A simulation model based upon factors regulating distribution and population dynamics of cattle fever ticks, Boophilus annulatus and B. microplus, on rangelands of the Northeastern Mexico-United States border region was found to reasonably represent interactions of season and habitat type. Three submodels represent tick development on cattle, tick development in the environment, and cow movement among three different habitat types. Simulated populations in grass tended to be smaller but with more abrupt peaks than those in mesquite and mixed-brush canopied habitats. Three generations were produced in grass from infestations beginning in January. Generations were less well marked in mesquite and mixed-brush due to the comparatively extended survivorship of larvae in these habitats. Sensitivity analysis of host-larvae encounter rate showed the model to be highly sensitive to this variable when all other factors are constant and demonstrated that utilization of a landscape by host animals is a powerful determinant in Boophilus population dynamics.