Vigilance behavior is considered as an effective strategy for prey species to detect predators. An individual benefits from living in a group by reducing the time spent being vigilant without affecting the probability of detecting a predator. However, the mechanism producing a decrease in vigilance with increasing group size is unclear. Many models of vigilance assume that group members scan independently of one another. Yet in recent studies, the other two patterns of vigilance, coordination and synchronization, were reported in some species. In two summers (2018 and 2019), we studied the group size effect on vigilance and foraging of Tibetan wild ass in Chang Tang Nature Reserve of Tibet. We also tested whether individuals scan the environment independently, tend to coordinate their scans, or tend to synchronize their vigilance. The results showed that individuals decreased the time spent on vigilance with increasing group size, while increased the time spent foraging. Group members scanned the environment at the same time more frequently and there was a positive correlation between group members’ behaviors, indicating that Tibetan wild asses tend to synchronize their vigilance.

In predator-prey interactions, various factors affect the prey's perception of risk and decision to ee. Gaze sensitivity, the ability to react to the presence, direction, or movement of the head and eyes, has been reported in many birds and they could recognise not only the head direction but the subtle difference in eye direction. But few studies focused on variation in sensitivity to human gaze in relation to other risks and costs. Here, we studied the in uence of human gaze on the escape behaviour of Azure-winged magpies (Cyanopica cyanus) and investigated the effects of breeding state and directness of approach on gaze sensitivity. In Experiment 1, we tested whether magpies showed different sensitivity to human gaze according to age class and breeding state when being approached directly. The results showed that the breeding state could affect the ight initiation distance (FID), with adults in the breeding season having a shorter FID. Meanwhile, only adults were found to be averse to direct human gaze and juveniles showed no sensitivity, implying that gaze aversion was not innate. In Experiment 2, we conducted three different gaze treatments on adult magpies in the breeding season under three bypass distances (0m, 2.5m, 5m). The results showed that directness of approach had no effects on FID, while the sensitivity to human gaze differed under three bypass distances. Adults could clearly recognise human head and eye direction at a certain bypass distance (2.5m). Our study reveals the cognitive ability of Azure-winged magpies to human head and eye direction and the effects of additional cost and risk, which may provide further insights into human-wildlife interactions, especially for birds in urban habitats.

In predator-prey interactions, various factors affect the prey's perception of risk and decision to flee. Gaze sensitivity, the ability to react to the presence, direction, or movement of the head and eyes, has been reported in many birds and they could recognise not only the head direction but the subtle difference in eye direction. But few studies focused on variation in sensitivity to human gaze in relation to other risks and costs. Here, we studied the influence of human gaze on the escape behaviour of Azure-winged magpies (Cyanopica cyanus) and investigated the effects of breeding state and directness of approach on gaze sensitivity. In Experiment 1, we tested whether magpies showed different sensitivity to human gaze according to age class and breeding state when being approached directly. The results showed that the breeding state could affect the flight initiation distance (FID), with adults in the breeding season having a shorter FID. Meanwhile, only adults were found to be averse to direct human gaze and juveniles showed no sensitivity, implying that gaze aversion was not innate. In Experiment 2, we conducted three different gaze treatments on adult magpies in the breeding season under three bypass distances (0m, 2.5m, 5m). The results showed that directness of approach had no effects on FID, while the sensitivity to human gaze differed under three bypass distances. Adults could clearly recognise human head and eye direction at a certain bypass distance (2.5m). Our study reveals the cognitive ability of Azure-winged magpies to human head and eye direction and the effects of additional cost and risk, which may provide further insights into human-wildlife interactions, especially for birds in urban habitats.

Group living animals form striking aggregation patterns and display synchronization, polarization, and collective intelligence. Though many collective behavioural studies have been conducted on small animals like insects and fish, research on large animals is still rare due to the limited availability of field collective data. We used drones to record videos and analysed the decision-making and behavioural spatial patterns in orientation of Kiang (Tibetan wild ass, Equus kiang). Leadership is unevenly distributed among Kiang, with the minority initiating majority behaviour-shift decisions. Decisions of individual to join are driven by imitation between group members, and are largely dependent on the number of members who have already joined. Kiang respond to the behaviour and position of neighbours through different strategies. They strongly polarize when moving, therefore adopting a linear alignment. When vigilant, orientation deviation increases as they form a tighter group. They remain scattered while feeding and, in that context, adopt a side-by-side alignment. This study reveals partially-shared decision-making among Kiang, whereby copying neighbours provides the wisdom to thrive in harsh conditions. This study also suggests that animals’ spatial patterns in orientation depend largely on their behavioural states in achieving synchronization.