2017 年 5 巻 2 号 p. 1-8
In this study, we describe a transition in the distribution of Japanese serow (Capricornis crispus) in the Suzuka Mountains Japanese Serow Protection Area, along the border between the Mie and Shiga Prefectures. We sampled serow distributions using camera traps at high and low elevations and light census methods in high elevation areas. Two and five cameras were placed in high elevation areas in 2014 and 2015, respectively, and light censuses were conducted monthly, except during the snowy season. Additionally, we placed two and four cameras in low elevation areas in 2014 and 2015, respectively. Despite a report of high serow density in the 1970s in high elevation areas, we found no evidence of the species. However, in low elevation areas, where serows were rarely found in the 1970s, we found the species at all camera locations and confirmed the birth of offspring. These results show that the distribution of serows in the protected area is contracting. Second, we documented changes in serow distribution by analyzing the results of monitoring data collected five times at 5-9-year intervals. In the 1980s, serow density in the center of the protected area (high elevation) was greater than that along the edges (low elevation). More recently, this pattern changed such that densities declined in both areas. In contrast, the density of Sika deer (Cervus nippon) has increased rapidly. The effect of increasing populations of Sika deer on Japanese serow density should be examined, and an action plan for serow conservation should be developed.