Habitat selection and movement ecology of Eastern Hermann’s tortoises in a rural Romanian landscape

Background/Question/Methods

Understanding wildlife movements and habitat selection are critical to drafting conservation and management plans. We studied a population of eastern Hermann’s tortoise (Testudo hermanni boettgeri) in a traditionally-managed rural landscape in Romania, near the northern edge of the species geographic distribution. We used telemetry to radio-track 24 individuals between 2005 and 2008, and performed a Euclidian distance-based habitat selection analysis to investigate habitats preferred by tortoises at both population (2^nd order selection) and individual (3^rd order selection) home range scales. 

Results/Conclusions

Tortoises in our study area had small home ranges (mean = 3.79 ± 0.62 ha) that did not differ by gender or season (pre- and post-nesting seasons). Their movement ecology was characterized by short-distance, relatively infrequent movements (daily mean = 31.18 ± 1.59 m), apparently unaffected by habitat type. In contrast to other studies, movements of males and females were of similar magnitude. At the individual home range scale, tortoises selected for grassland and shrub habitats, avoided forests, and used forest edges randomly. At the population home range scale, grasslands and shrubs were preferred, but tortoises also showed affinity to forest edges. Creeks were avoided at both spatial scales. Our results suggest that despite higher selection of grasslands at both scales, tortoises select home ranges based on an association of habitats rather than a particular habitat. As such, avoiding land conversion to other uses (e.g., cropland) and maintaining habitat heterogeneity through traditional practices (e.g., manual mowing of grasslands, livestock grazing) are critical for the persistence of tortoise populations.