Simple SummaryInfrared camera technology was used to study the space occupancy, activity rhythm, and sexual segregation of white-lipped deer (Cervus albirostris) in the Yarlung Zangbo River basin of Tibet for two years. The results showed that, in Jiacha Gorge, the occupancy of white-lipped deer is high, belonging to crepuscular activity pattern mammals. White-lipped deer have two activity peaks in the forest (May, October), and most of their activities are in the form of mixed groups of male and female during breeding and wintering. This study provides important information for the habitat utilization of white-lipped deer, and offers a scientific basis and theoretical support for the protection of white-lipped deer in Jiacha Gorge in the Yarlung Zangbo River basin.AbstractThe white-lipped deer (Cervus albirostris)is a rare and endangered species found in the Qinghai-Tibet Plateau in China. To understand the space occupancy, activity rhythm, and sexual segregation of the white-lipped deer, 24,096 effective photos and 827 effective videos were captured using infrared cameras from February 2020 to January 2022. The ecology and behavior of the white-lipped deer in Jiacha Gorge were studied in more detail using site occupancy models, relative abundance index, and other technologies and methods. The results show that The occupancy predicted by the model exceeds or approaches 0.5. The occupancy increases with greater altitude and with larger EVI values, while the detection rate increases with altitude only during spring and decreases with EVI values only in summer. The daily activity peaks for white-lipped deer were observed from 7:00 to 11:00 and 17:00 to 22:00, with annual activity peaks occurring from April to June and from September to November. From July to the following January, white-lipped deer mostly move in mixed-sex groups, while during the remainder of the year, they predominantly associate with individuals of the same sex. Climate, vegetation coverage, food resources, and human disturbance collectively influenced the behavior and habitat utilization of white-lipped deer. The foundational research conducted on white-lipped deer over the past two years is expected to enhance the basic understanding of white-lipped deer in the Qinghai-Tibet Plateau and contribute to future protection and management decisions.