Abstract:

Aim: Wildlife modify their daily activity to satisfy food demands, to breed, or to avoid mortality risk. Assessing patterns of wildlife activity is crucial for understanding adaptations to inter-species competition, predation risks, and human disturbances. Sika deer (Cervus nippon) is a primary prey species for tigers (Panthera tigris) and leopards (P. pardus) in the Northeast China. However, the sika deer’s habitat is disturbed by roads. This study assessed the influence of road disturbances on the activity patterns of sika deer, considering their gender, age, reproductive status, and seasonal activity. The aim is to deepen our understanding of behavioral changes in animals due to human disturbance, providing a scientific basis for future conservation and management of sika deer, tigers, and leopards in the Northeast China Tiger and Leopard National Park.

Methods: From April 2021 to March 2022, we deployed 41 pairs of camera traps along the road in Northeast China Tiger and Leopard National Park to collect data of sika deer activity. Based on gender, age, and reproductive status of individuals, we classified sika deer into five sex/age groups. We used the kernel density method to estimate diel activity patterns and activity levels of sika deer, based on 9,825 independent detections of the species. Furthermore, we compared the activity levels and patterns across different seasons, sex/age groups, and levels of road disturbance.

Results: Peak activity of sika deer was observed in June and October. Diel activity patterns varied across seasons, with sika deer being crepuscular during spring and summer, nocturnal in autumn, and diurnal in winter. Diel activity patterns differed between age and sex groups of sika deer; fawns were diurnal, while adults were predominantly crepuscular, with only adult males having an increased probability of nocturnal activity. The negative effects of roads on the activity patterns of sika deer were mainly observed in autumn, which coincided with peak human and vehicular activity. Moreover, sika deer exhibited significantly reduced activity levels near roads during autumn. At sites close to roads, all sex/age groups of sika deer tended to decrease their activity levels.

Conclusion: This study is the first to document seasonal differences in activity patterns and variations among sex/age groups of sika deer in Northeast China. Additionally, it addresses the impact of roads on the diel activity patterns and activity levels of sika deer, revealing that during the high-traffic autumn season, road disturbances significantly affect their activity patterns. Across sex/age groups, sika deer respond similarly to road disturbances, with a shorter period of activity to minimize exposure to road risks while maximizing food intake. Our study emphasizes the negative impact of human activities on the behavioral patterns of this ungulate species. Additionally, it also highlights the behavioral plasticity of sika deer in response to anthropogenic disturbance, suggesting their ability to efficiently utilize alternative food resources. Our methodology provides insights into wildlife management strategies, and we recommend long-term monitoring of wildlife population dynamics and behavioral responses, especially in the Northeast China Tiger and Leopard National Park.

Key words: sika deer, camera traps, activity pattern, activity level, road