Leveraging animal tracking to combat wildlife crime: GPS-tagged vultures and wolves as sentinels of other species' poaching.

From satellite imagery to drones or camera traps, remote technologies are increasingly used to enhance wildlife crime detection worldwide. Whereas remotely tracking individuals allows for prompt detection of their illegal persecution, much less attention (concentrated in oceanic ecosystems) has been paid to tagged animals as sentinels to detect other species' poaching through their interspecific interactions. We illustrate this potential in terrestrial ecosystems by showing how GPS-tagged vultures, able to quickly locate dead animals, and GPS-collared wolves enabled the detection of poached wildlife of other species (i.e., illegally shot or snared wild ungulates and carrion-baited illegal snares) in Europe. We further discuss how these interspecific interactions could be systematically monitored to improve detectability of poaching events. Considering the wide variety of tracked wildlife across ecosystems, taking their interactions (e.g., scavenging) into account will enhance the utility of animal-borne technologies in addressing illegal wildlife persecution.