Résumé
The Sterile Insect Technique (SIT) is a target-specific and environmentally friendly method for controlling invasive agricultural pests such as tephritid fruit flies. Although male-only releases represent the current gold standard, the high costs and technical complexity of sex-sorting technologies make bisexual releases a practical necessity in some regions. So far, despite the occasional implementation of bisexual programs in the field, mathematical models have largely overlooked the role of sterile females, whose biological impact remains a subject of contrasting results in the literature.</p><p>To address this theoretical gap, this paper introduces an ODE population dynamics model designed to quantify and compare both unisexual and bisexual releases, incorporating a detailed characterization of wild-sterile mating and territorial interactions. We characterize the system's equilibria and establish the existence of a critical release rate threshold required for population eradication across a wide range of biological parameters. Through theoretical analysis and numerical simulations, we examine the sensitivity of the critical threshold, extinction time, and total release effort to sterile female parameters. In particular, our findings highlight the crucial role of mating preferences and territorial competitiveness in determining SIT efficiency. Formulated in full generality and applied to the management of B. dorsalis in La Réunion, our findings provide a mathematical framework for comparing the efficiency of unisexual and bisexual SIT strategies.