Environmental DNA for conservation

Detection and monitoring of wildlife species of concern is a costly and time-consuming challenge that is critical to the management of such species. Tools such as lures and traps can cause unnecessary stress or other health impacts to sensitive species. Development and refinement of tools that provide means to detect rare and elusive species without requiring contact with them reduce such impacts. Further, the potential of detection after the target species has moved on from a sampling site could allow for higher potential for detection of rare species. The ability to amplify DNA from environmental samples (e.g. water, soil, air, and other substrates) has provided a non-invasive method for detection of rare or elusive species while reducing negative impacts to wildlife. Like other non-invasive methods, such as cameras, there are methodological pitfalls associated with environmental DNA (eDNA) sampling to consider. Each study system will provide unique challenges to adequate eDNA sampling. Thus, pilot studies are critical for successful implementation of a larger-scale detection and monitoring study. This chapter will describe the benefits and challenges of using eDNA, detail types of eDNA sampling, and provide guidance on designing appropriate study design and sampling schemes. Empirical studies using eDNA applied to wildlife conservation efforts will be highlighted and discussed.