Field body temperatures and microclimatic influences in Hermann’s Tortoise, Testudo hermanni Gmelin, 1789, from Thrace

Abstract

Temperature is considered a fundamental factor in reptile ecology because their body temperature generally varies depending on environmental temperature. This study investigated the thermal ecology of Testudo hermanni populations inhabiting two different habitat types in the Thrace region (Karakoç/Kırklareli–open habitat, Keşan/Edirne–closed habitat) by examining the relationship between body temperatures (Internal Body Temperature: T_int and External Body Temperature: T_ext), microclimatic parameters (Substrate Temperature: T_s and Air Temperature: T_air), and morphological features (Body Weight: BW and Straight Carapace Length: SCL). Additionally, the effect of different weather conditions (cloudy and sunny) on the body temperatures of the populations was determined. Significant positive correlations were found between body temperatures and microclimatic parameters in both populations, whereas no significant relationship was detected between body temperatures and morphological features. Behavioural analyses indicated that activities such as basking and movement were associated with higher body temperatures. It was also found that individuals had higher body temperatures under sunny weather conditions. However, no significant difference in body temperatures was detected between the two populations, one inhabiting the densely wooded, closed habitat of Keşan and the other in the sparsely vegetated, open habitat of Karakoç. The results suggest that T. hermanni individuals have a high capacity to maintain optimal body temperatures under varying environmental conditions. This ability is crucial for the species’ survival in the face of environmental challenges. However, increasing habitat fragmentation and habitat loss may significantly limit this adaptability. Moreover, rising temperatures could affect thermoregulation strategies, potentially threatening the long–term survival of populations. Future studies should focus on the long–term impacts of climate change on the thermal ecology and habitat use of T. hermanni to contribute to effective conservation strategies.