## 1 Introduction  
The Sterile Insect Technique (SIT) is an environmentally friendly and technically advanced approach to pest control based on the use of mass-produced sterile live insects to control populations of wild individuals of the same species. Numerous regional and subregional pest suppression and eradication SIT operations have been and are being conducted against a range of insect pests such as screwworms, testes flies, tephritid fruit flies, moths, mosquitos and others [1, 2]. Of these, medfly, the Mediterranean fruit fly, _Ceratitis capitata_ (Wiedemann), is the target of the largest operations conducted in the US, Mexico, Guatem, Argentina, Chile, Australia, Spain and other countries [3]. Medfly is recognized as one of the most destructive agricultural pests worldwide. Originally native to sub-Saharan Africa, the species is now cosmopolitan, present throughout the year in most tropical and subtropical regions, and seasonally established in temperate areas [4, 5]. Medfly can infest the fruits of more than 300 plant species and lives across a wide variety of climatic zones [6; 7]. _C. capitata_ is listed as an A2 quarantine pest by the European and Mediterranean Plant Protection Organization (EPPO). Its economic impact is substantial, prompting some countries, such as the United States (mainland), Australia and Japan, to implement stringent phytosanitary regulations. These measures include strict import controls and quarantine procedures aimed at preventing the introduction and potential spread of this pest [4]. The effectiveness of SIT against medfly is significant when applied on a large, regional scale [8; 9], following the recommended \"area-wide\" approach [10]. The spatial scale of SIT operations ranges from the largest programs in Mexico and Guatema in Central America [11] to more limited eradication operations after local medfly detections in California, USA [12]. Generally, their ultimate goal is complete or near-complete elimination of medfly from the treated area in order to create low-prevalence or medfly-free areas or to eradicate new medfly incursions into areas declared medfly-free. Very detailed and comprehensive guidelines and protocols are available to guide and support timely medfly detection, SIT implementation, and post-treatment verification of eradication [12; 13]. In Europe, however, in the highly fragmented, multi-owner setting typical of the Mediterranean landscape, the implementation of such approaches is difficult. SIT programs, such as in Valencia, Spain, or in the Neretva Valley, Croatia, have not only a more limited spatial scale (4000 hectares in the latter), but importantly, also a different approach, aiming at seasonal medfly suppression rather than its elimination [14; 15; 16]. Although SIT technology was originally designed for large scales, there is also interest in including it in the methodological repertoire of IPM methods, and trying it at a very local, even farm-like scale [17; 18; 19]. Recent detections of _Bactrocera dorsalis_ (Hendel) in Europe [20; 21; 22] have also raised interest in the use of SIT in emergency response to very local invasions or preventive releases in spatially limited and isolated or semi-isolated zones at high risk of invasion, such as around fruit import ports or markets. Therefore, while fully recognizing the numerous limitations of such an approach, a need arose to investigate the feasibility of SIT on a smaller scale. Consistent with the original concept of SIT implementation, available decision support tools and models focus on interventions at large spatial scales [23] and therefore tend to ignore the influence of fine-grained terrain structures and their impact on the behavior of both wild and released sterile medflies. Consequently, they offer little guidance for small-scale SIT operations in locally diverse landscapes.