FACING HABITAT REDUCTION IN YOUR OWN SHELL: PATTERNS OF NON-LETHAL INJURIES IN THE ENDANGERED TORTOISE TESTUDO HERMANNI IN ITALY

摘要

Shell damage occurs frequently in tortoises, and represents evidence of non-lethal injuries of both natural and anthropogenic origins. By analyzing the occurrence of non-lethal injuries in 130 free ranging Hermann's Tortoises (Testudo hermanni) in Italy, we observed that significantly more damage was present (nearly 90% of the sampled tortoises) at sites 1 km from cultivated areas. Further, we found an increased prevalence of wounds and enhanced severity of damage to individuals (considering both the carapace and plastron) at these sites. Interestingly, near agricultural activities, most injuries were concentrated on the rear of the carapace. This pattern of injuries is compatible with threat sources coming from above, such as agricultural machinery. As expected, the carapace was the most injured shell region, showing different kinds of damage: abrasions (superficial or deep enough to expose the bony layer), indentations, fractures, and fire damage. The incidence of individuals with abrasions and minor indentations (the most common injuries) did not vary between sexes or by body size; thus, injuries were seemingly independent from the rates of activity and the distances traveled by tortoises, which usually vary with sex and age. We found, however, shell deformation due to deep fractures and fire damage more frequently in older (bigger) tortoises. Given the progressive reduction and fragmentation of T. hermanni habitat due to the expansion of human activities, the presence of uncultivated buffers and the protection of natural and semi-natural areas inside agricultural landscapes should be considered as a key target for T. hermanni protection.