Landscape fragmentation and spatial ecology of the yellow-spotted mountain newt (Neurergus derjugini) in the context of climate and land use change (2002–2024)

The yellow-spotted mountain newt (Neurergus derjugini), a vulnerable amphibian endemic to western Iran and northeastern Iraq, faces significant threats from habitat loss and fragmentation. This study evaluates habitat suitability, identifies core habitats and connectivity pathways, and quantifies land use and land cover change (LULCC) in the species’ range from 2002 to 2024. Using ensemble species distribution models, we integrated climatic, topographical, and anthropogenic variables, achieving high predictive accuracy (specificity and sensitivity >92 %). Precipitation during the wettest month (18 %) and annual mean temperature (13.35 %) emerged as the most influential environmental factors. Core habitat analysis revealed that only 11.69 % of suitable habitats and 14.63 % of connectivity corridors fall within protected areas, leaving the majority of the species' range exposed to anthropogenic pressures. Connectivity modeling identified the southern range as a critical dispersal corridor, but fragmentation caused by roads and infrastructure poses a significant threat to gene flow. LULCC analysis indicated substantial transformation in land cover, with residential and agricultural areas expanding by 6.6 % and 6.75 %, respectively, while rangelands and water bodies declined by 8.84 % and 1.56 %. Urbanization intensified, as residential land cover increased from 5.92 % to 22.84 %, edge density rose from 1.85 to 3.83, and patch density grew from 1.65 to 4.20, further exacerbating landscape fragmentation. These findings underscore the urgent need for targeted conservation measures, including the expansion of protected areas, restoration of habitat connectivity, and mitigation of anthropogenic impacts. This study provides a spatially explicit framework for conservation planning, emphasizing the importance of addressing habitat fragmentation and climate change to ensure the long-term survival of N. derjugini and the preservation of its ecosystems.