Identifying Core Persistence Areas for Emys orbicularis Through an Integrated Environmental—Spatial Modelling Framework in the Andalusia Region (Spain)

Abstract

Understanding the distribution of Emys orbicularis in Andalusia is essential for assessing its conservation status within one of the most fragmented sectors of its Iberian range. In this study, we applied a modelling framework integrating environmental favourability, spatial structure, and their intersection to identify the factors determining the species’ presence across the Andalusian territory. All presence records were obtained from field surveys and long-term monitoring programmes conducted by the authors, while environmental and spatial predictors were compiled from publicly available databases and processed following the modelling methodology developed by Santoro et al. A consistent pattern emerged across all models: E. orbicularis is strongly associated with forested riparian systems, stable aquatic habitats, and low levels of disturbance, while its distribution is constrained by a marked north–south gradient associated with the Sierra Morena mountain range. The species also shows a historical and continuous presence in Huelva province, including coastal areas, and traditionally occupied parts of the western Betic systems and the Cádiz coastline. Integrating environmental and spatial components allowed us to capture both habitat suitability and the spatial processes limiting the species’ presence. The intersection model, which synthesises the results of both analyses, provided the most reliable representation of the species’ potential distribution by reducing false positives and highlighting core areas of persistence associated with hydrological stability and landscape connectivity. We also observed a marked reduction in the area of occupancy derived from the records, consistent with the initial hypothesis regarding the species’ current status.