Herring gull aversion to gaze in urban and rural human settlements

With an increasing human population and expansion of urban settlements, wild animals are often exposed to humans. As humans may be a threat, a neutral presence or a source of food, animals will benefit from continuously assessing the potential risk they pose in order to respond appropriately. Herring gulls, Larus argentatus, are increasingly breeding and foraging in urban areas, and thus have many opportunities to interact with humans. We recently found that herring gulls take longer to approach food when being watched by a human. However, it is not known whether aversion to human gaze arises from experience with humans, and whether individual differences in responsiveness are a result of differential exposure. Here, we tested whether herring gulls' responses to human gaze differ according to their age class and urbanization of their habitat. We measured the gulls' flight initiation distance when an experimenter approached with either a direct or an averted gaze. Neither gull age class nor urbanization significantly influenced the effect of human gaze on flight initiation distance. However, as recently fledged juveniles responded strongly to the experimenter's gaze, aversion to human gaze may not require extensive exposure to humans to develop. Gulls in urban areas could be approached more closely than those in rural areas, consistent with findings in other species. These results indicate that gaze aversion is present early in development and that exposure to humans may influence gulls' responses to perceived risk from humans. Investigating the processes generating individual differences in responses to humans will provide further insights into human–wildlife interactions and the effects of urbanization.