Human encroachment suppresses play behaviour of parkland fallow deer fawns

While contact with nature is beneficial for human health and wellbeing, the increasing human population has resulted in greater contact with urban wildlife, which, in turn, results in animal welfare and behaviour being negatively affected. Although adult animals may habituate to people, how human presence impacts the behaviour of juveniles is poorly understood. Play is central to juvenile physical, cognitive and social development and occurs when individuals are in a stress-free state. With this in mind, we investigated how human disturbance affects play in parkland fallow deer fawns, Dama dama . Disturbances were commonplace: across 572 unique observations, we recorded more than 3000 pedestrians within 50 m of the deer, 60% of whom directly approached the deer. We found that, while fawns ignored pedestrians who avoided approaching them, they interrupted play when directly approached. Fawns returned to play quickly following disturbance, yet the suppressive effects of disturbance persisted over time, as fawns failed to demonstrate any habituation. Additionally, the probability of observing fawns playing was highest in areas with typically low pedestrian activity, such as woodlands or locations restricted from public access, regardless of whether pedestrians were present at the time of observation. Combined, our results indicate that human proximity alone is not disruptive; however, encroachment has limited but sustained suppressive effects on play and the cumulative effects of lost play time could be significant given the key role of play in development. We suggest that play, as a natural feature of juvenile behaviour, can be a valuable indicator for the impact of human disturbance in many species. Furthermore, as 60% of the pedestrians observed in this study actively encroached on the deer, we conclude that changes to human behaviour are critical for the development and wellbeing of juvenile animals. • Human-wildlife interactions in public parks can affect animal behaviour. • Play, a key juvenile behaviour, was suppressed by pedestrian encroachment. • Pedestrians avoiding direct approaches had no measurable impact on fawn play. • Play suppression was brief, yet fawns showed no habituation to encroachment. • Park management should limit direct human-animal contact to protect juveniles.