Analysis of Occupancy and Activity Pattern of the Water Deer Using Remote Camera Traps

ABSTRACT Water deer ( Hydropotes inermis ) are classified as “Vulnerable” on the IUCN Red List due to their declining population trend, indicating global conservation concern. However, water deer are considered a harmful species in South Korea, where the population is relatively abundant. The population status of water deer varies across their geographical range, but information on their distribution remains limited due to insufficient research and reporting. This study therefore aimed to identify the environmental variables influencing the distribution of water deer and to provide insights into their daily behavior patterns. Camera traps were deployed at 108 points within 22 grid cells (each 5 km × 5 km) located in the central‐eastern part of the Korean Peninsula from March to September 2021. Water deer were detected 92 times across 17 grid cells. A single‐season occupancy model revealed that occupancy decreased with an increase in normalized difference vegetation index ( NDVI ) (: −3.36 ± 0.17), which is presumed to be related to the use of forbs or low woody plants as food resources. Detection was influenced by slope, with higher slopes likely limiting mobility and thereby reducing detection (: −0.60 ± 0.15). The diurnal behavior patterns were confirmed to be crepuscular, with activity primarily around sunrise and sunset. These findings are expected to enhance understanding of this species and may be used for the management of water deer as a problematic species in South Korea, as well as for international conservation efforts.