Abstract Road-kill can lead to a sharp local decline of herpetofauna species. For this reason, transportation agencies are more and more interested to implement mitigation measures in order to eliminate this threat. The present study proposes to identify the railroad network induced threats at a railroad segment spatial scale on Getic Tableland, south-western Romania, by highlighting associated mortality hot spots for Testudo hermanni boettgeri. The railroad segment was chosen due to the reported road-kills and high traffic volume. In order to identify road associated mortality hot spots, we adapted a gravity model by including a weighting coefficient for overtaking obstacles. The model was adapted after observing that the cuts, fills, ditches and guardrails can change the tortoises behavior, making them avoid dangerous crossings, thus influencing the distribution of hot spots. As a main result, our study managed to adapt a gravity model for a more accurate assessment of railroad associated mortality. The average value of inter-habitat interaction is reduced by 23.37% after introducing the coefficient of overtaking the obstacles. However, despite the numerous obstacles, at a home range spatial scale, the maximum inter-habitat interaction value is not decreased, the range being stable (range = 0 - 99.66). Instead, the spatial extent of the hot spots is modified because of the increased territorial dependence and home range multi-annual stability, both severely threatening the tortoise that have a home range bisected by a major railroad. Our study accurately identifies the hot spots, which is particularly important in planning mitigation efforts, for building effective underpasses and fences systems.
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