Importance of woody patches and vegetation heterogeneity in Texas tortoise microhabitat use

Résumé fourni par la source

Microhabitat sites provide important resources and thermal conditions to reptile species that can vary spatially and temporally. This study assessed Texas tortoise Gopherus berlandieri microhabitat use and its relationship with carapace temperature during their active (April–October) and inactive seasons (November–March) between January 2023 and February 2024 in a thornscrub savanna in southern Texas, USA. Other studies have examined Texas tortoise microhabitat associations during the active season, but none have assessed these associations during months when they are inactive, a period important to their survival throughout the year. To do this, we collected ground cover and overhead canopy cover data at locations of telemetered tortoises and paired random locations. We compared microhabitat variables by location type to determine if tortoises associated with certain cover types. Then, we assessed the relationship between microhabitat variables at tortoise locations and carapace temperature using linear mixed models. Results indicated that carapace temperature was most strongly influenced by hour of day year‐round and air temperature during the inactive season rather than associated microhabitat cover types year‐round. Tortoises associated with higher values of woody‐stemmed vegetation ground cover and overhead canopy cover than were available at random locations during both seasons. In addition to the importance of woody vegetation, the data suggest that tortoises most often used microhabitats with at least double the amount of grass and litter ground cover compared to other microhabitat variables. Managers prioritizing Texas tortoise conservation can use this information to manage vegetation to meet year‐round needs of tortoises by aiming for variety in vegetation cover with woody patches dispersed throughout the landscape. Our findings highlight the importance of considering spatial and temporal microhabitat components that affect reptile success, such as the thermal properties and composition of available cover types, in conservation efforts.

Ce résumé expose les affirmations des auteurs. BNTIC ne l’interprète pas comme une validation indépendante des résultats.