Sex-specific divergence in microhabitat use and activity patterns in fire salamanders: temperature matters

Kristin Rose Szydlik, Carolin Dittrich , Bibiana Rojas

Human-driven climate change and habitat degradation cause alterations in the spatial and temporal availability of natural resources, forcing wildlife to adjust their interactions with the environment in order to survive. To identify changes and promote effective conservation measures within the limited suitable habitats available, it is crucial to better understand habitat use. Activity patterns influence the exposure to both risks and opportunities, whereas microhabitat selection reflects fine-scale decisions that can buffer individuals against environmental stressors and facilitate access to essential resources. Amphibians are especially vulnerable to climate change and habitat degradation, making them suitable models for studying the impact of these stressors on different aspects of behavior. To investigate activity patterns and microhabitat selection under nearly undisturbed conditions, we conducted standardized transect walks in a minimally disturbed habitat of the fire salamander (Salamandra salamandra), an emblematic amphibian of the Vienna Woods, between mid-November 2023 and mid-November 2025. Based on data from 316 unique adult individuals, our results reveal sex differences in activity depending on the temperature of the surrounding microhabitat, with females preferring higher temperatures than males. The observed sex ratio differed significantly between seasons, but males were more active than females throughout all seasons. Individuals were disproportionately associated with dead wood and trees compared to their availability, suggesting a preference for these microhabitat structures. In line with the results for the microhabitat use, the spatial activity was unevenly distributed throughout the whole study site, with higher densities where dead wood accumulated and lower densities around open areas. Insights into habitat use can help predict a species' ability to cope with novel and rapidly changing conditions and facilitate the development of effective conservation strategies.