Analysis of Spatial Distribution in Fruit Fly Eradication

Abstract

Spatial pattern of distribution of the fruit flies caught in traps under the implementation of the male annihilation method (MA) and sterile insect technique (SIT) was analysed. As for MA applied to Dacus dorsalis, the index of dispersion of individuals, Iδ , and the density-contagiousness coefficient, β , in the frequency distribution of flies caught in traps were useful to predict a successful eradication. In SIT for D.cucurbitae, sterile flies released could be conveniently dispersed to local patches where wild flies were abundant. However, the correlation coefficient between the number of sterile flies and that of the wild flies caught in traps in the area where SIT was being implemented was often low. This observation suggests that the effect of SIT is not homogeneous among local patches. These facts suggest that the analysis of the spatial distribution of fruit flies in the target area of the eradication project is important to devise a strategy for the implementation of SIT and also for the evaluation and analyses of the eradication processes.