Time to leave? Immediate response of roe deer to experimental disturbances using playbacks

Abstract

Despite frequent exposure to disturbances or threats, some species seem to be successful in human-dominated landscapes. In order to better understand how these species respond to disturbance linked to human activities, we studied the immediate response of roe deer to playback experiments conducted in an agricultural landscape where human activities are omnipresent and hunting is frequent. During two periods of contrasted hunting risk, we performed playback experiments (with dog barks or tractor engine noises) with experimenters that were either stationary or walked towards the deer. We modelled the probability of fleeing immediately after the start of the experiment. The probability of fleeing was around 0.3 when experimenters were located 100 m away from the deer and did not move but was greater when the experimenters were initially closer to the animal or approached closer to the animal during the experiment. Surprisingly, the responses of roe deer did not vary between periods of contrasting risk or in relation to the type of sound played. This study provides experimental evidence of a high level of reactivity of this sedentary species when confronted with disturbance. We argue that this may partly explain its success in human-dominated environments, allowing it to exploit the rich feeding resources provided by agricultural landscapes in a relatively safe way.