Sterile Insect Technique in a n-patch system with Allee effect and mass trapping: modeling, analysis and simulations

Using results from monotone systems theory, we first derive a sufficient condition guaranteeing the elimination of the wild population through SIT, which relies on the sign of the Perron value of a certain Metzler matrix. When an Allee effect is naturally present, releases are finite in time, and an upper bound of the control time is provided. We then formulate an optimisation problem aimed at minimising the total daily number of sterile insects released to ensure population elimination. We focus in particular on the oriental fruit fly, which significantly impacts mango orchards in La Réunion.

Through numerical simulations, we illustrate our theoretical results and study different scenarios, including some where releases are limited to certain orchards. Indeed, when implementing SIT in the field, some owners may be reluctant to allow releases on their property. We also consider additional control by mass trapping, which can affect the sterile insects entering trapped areas, and show that although it increases the critical number of sterile insects to be released daily, it reduces the duration of the SIT program. Mass trapping may thus decrease the total number of sterile insects released over the entire elimination program.