Wolves and their prey all fear the human "super predator"

Fear in, and of, the "big bad wolf" dominates much of the public discourse on human-wildlife conflict and much recent research in large carnivore ecology.^{1,2,3,4,5,6,7,8,9} Global surveys show humans kill prey at much higher rates than other predators,^10,11,12 and recent experiments have demonstrated corresponding paramount fear of humans and resulting community-level impacts in diverse mammals.^{13,14,15,16,17,18,19,20,21,22,23,24} Humans kill wolves at particularly high rates,^{1,3,5,6,10,25} yet fear of humans in wolves and resulting community impacts remain experimentally untested.^{1,5,6,8,14,21,26} In the absence of experiments, greater wolf nocturnality where humans are present is invoked as indicating wolves fear humans,^27,28,29 but alternative interpretations exist. We experimentally tested fear of humans in wolves and their ungulate prey and quantified their nocturnality in a representative human-dominated European landscape^1,28 using automated camera-speakers broadcasting playbacks of humans, dogs, or non-predator controls (birds).^{14,15,16,17,18,19,20} Wolves and their prey all significantly feared humans. Wolves (n = 101 independent trials) and their prey (n = 225) were more than twice as likely to run (p = 0.004), and twice as fast to abandon the site (p < 0.001), in response to humans compared with controls. Wolves and their prey were equivalently nocturnal, and were all significantly more nocturnal than humans (p < 0.001). Our results experimentally verify that fear of humans traps wolves and their prey in the dark,^1,29,30 thus corroborating the universality of wolves' fear of humans,²⁸ and thereby help re-focus the discourse on human-wolf conflict from ostensibly fearless wolves^1,5,6 to human food subsidies better explaining why fearful wolves risk encounters with the human "super predator."^{21,31,32,33,34,35}.