Environmental DNA Analysis for Japanese Giant Salamander in River Water Downstream from a Den

摘要

Environmental DNA (eDNA) analysis is a new tool to investigate the presence and distribution of aquatic organisms. For successful application of this method in the field, it is important to characterize the behavior of eDNA. In the present study, we examined the vertical distribution of eDNA derived from Japanese giant salamanders in river water. As a result of examination, eDNA from subjects was not detected in DNA extracted from a water sample collected in the bottom of liver, because large amount of PCR inhibitors were contaminated. However, after removal of inhibitors by further purification of DNA, significant difference in eDNA concentration was not observed among water samples collected in top, middle and bottom of liver. It showed that the surface water is most suitable for eDNA analysis. Next we investigated the horizontal distribution of eDNA. Our results revealed that the detectable area of eDNA was about 15m downstream of a den in which an old male giant salamander has been habitually living.