Stochastic Model of Spatial Spread and Control of Tsetse Flies (Diptera: Muscidae)

Abstract

A stochastic model is developed to study the spatial spread and control of tsetse flies, Glossina spp. In this model, the movement mechanism is described by the travel direction and distance of an individual tsetse fly, birth and death rates are described by probability distributions, and some control measures are considered. The model is used to estimate the straight-line distance traveled in the life span of a fly, and the distance fly populations will spread during a 10-yr period. Simulation results indicate that the straight-line distance traveled in the life span of a tsetse fly is <1.71 km from its birth place. The spread distance for fly populations is ≈18.7 km by the end of the 10th yr based on a 99% confidence prediction limit. Strategies of preventing tsetse flies from advancing to a tsetse-free region are examined. The probabilities that a fly crosses a protective barrier (buffer zone) are obtained for different control methods. The width of a protective barrier required to prevent the tsetse flies from advancing to a tsetse-free region is estimated.