Excellent performances of dogs to detect cryptic tortoises in Mediterranean scrublands

Mediterranean ecosystems are severely impacted by urbanization, habitat clearing, fires and landscape fragmentation; conservation actions are urgently needed. The protection status of a given area depends notably on the presence and detection rate of protected species. Further, habitat restoration, conservation translocations, or population reinforcement require precise information on the distribution of individuals. Thus, the success of important conservation measures relies on the capacity to locate individuals. Thanks to their sense of smell combined with high learning abilities, dogs have been used to track a wide range of biological targets. They generally surpass humans to detect cryptic species. In this study, we aimed at testing their detection performances with Hermann’s tortoises. This secretive reptile provides a typical case of threatened Mediterranean species where protection actions are hampered by low detection rates; especially because low population densities increase the risk of false negative results during surveys. The ability to detect and save individuals, for example before destructive land-work, might be crucial. We evaluated the detection ability of dogs to find tortoises with two experiments. First, field trials showed that relative detection rate was three times higher in dogs compared to well-trained humans. Then, and more importantly, the absolute detection rate of dogs to find radio tracked tortoises was excellent: after two trials, dogs rapidly located all the experimental tortoises dissimulated along different field transects. Overall, dogs were very efficient in finding tortoises, especially well-hidden individuals. More generally, the immense potential of trained dogs should be extended to improve the techniques to detect and protect Mediterranean reptiles.