Distribution modeling and evaluation of the habitat integrity of Testudo graeca zarudnyi (Testudines: Testudinidae) in Central and Southeastern Iran

One of the initial measures to planning the conservation strategies is knowing the ecological needs of a species and its favorite habitat. Species Distribution Modeling (SDM) is an applicable tool to achieve this goal. Zarudny's spur-thighed tortoise or Iranian tortoise (Testudo graeca zarudnyi) is one of three subspecies of spur-thighed tortoises found in Iran. To assess the conflicts threatening the habitat of this subspecies, the Maximum Entropy Algorithm (MaxEnt) was used. The purpose of this study was to evaluate the integrity of the T. g. zarudnyi habitat and discuss the conflicts threatening the suitable habitat of this taxon in Iran. First, 25 ecological variables were considered to evaluate the habitat suitability, including topographic, land use land cover, and climatic layers (19 Bios). Among climatic variables, only five of them were selected using Pearson correlation analysis at the level of 75%. Finally, 11 variables contributed to running the model. The cell size were set based on Bios cell sizes to prevent biases, only one presence point kept at each cell; therefore, 108 presence points were remained out of 137 occurrence data. The obtained model had a high degree of predictability (AUC= 0.911). Results showed that Zarudny's tortoise favorites good to moderate vegetation structure. Hence, areas with higher vegetation cover and an annual average temperature of 20°C are optimal, which emphasizes the importance of landuse changes in both the range dynamics and the conservation of this subspecies in Iran. Considering the overlap of the protected areas with the suitable habitat of Zarudny's tortoise revealed that insufficient amounts of suitable habitat are protected. Hence, considering the vulnerable conservation status of Iranian tortoise, the importance of establishing more protected areas through the suitable habitat of his taxon is emphasized.