A ground surface rolling method for detecting environmental DNA of terrestrial animals

Biological information obtained from environmental DNA has been helpful for conservation of ecosystems and biodiversity. Methods for environmental DNA of terrestrial habitats are limited such as sampling of water near terrestrial habitat and of shoveled soil, whereas those of aquatic habitats are well-established. We developed a method using a sampler for terrestrial habitat utilizing a combination of a simple rotating body and a single-use non-woven fabric collector as a sampler, enabling sample collection from wide area of various surfaces without power supply. The sampler was applied to collect 90 ground surface and 29 water samples in a secondary nature environment, resulted in the detection of 53 species of birds and mammals in total. The result covered 92% of the species detected by cameras installed in front of the sampling areas, validating the sensitivity of the method. Time course analysis also revealed that the timing of the detection of birds matched that of the birds actual arrival. These results suggest that our labor-saving method could provide accurate and time-resolved data for biodiversity monitoring of terrestrial areas. Combining with established aquatic environmental analysis, the sampler would enable systematic monitoring of both aquatic and terrestrial habitats, enhancing our understanding of the whole ecosystem.