Abstract
It is necessary to monitor the distribution of an invasive species, the small Indian mongoose, Herpestes javanicus, on Amami-Ohshima Island in order to eradicate them effectively. To assess this distribution, tracking-tunnels were placed on the forest floor at points along four forest roads in the summer of 2006 and winter of 2007. Mongoose foot prints were seen in 94 of 557 (16.9%) tracking-tunnels in the summer and in 78 of 347 (22.5%) tracking-tunnels in the winter. Within a 14-km radius of the original release point of the mongoose along the Amami Central Forest Road (ACF-Road), the percentage was as high as 41.4%, although mongooses are trapped continuously in this area. This high percentage is probably because they are trap shy, and their density may have remained unchanged. We observed signs of invasion at points more than 30km from the original release point along the ACF-Road, and in the northern part of Amami-Ohshima Island. As part of the process of eradicating the mongoose, tracking-tunnels are a very useful tool for monitoring surveys.
