Beyond species detection—leveraging environmental DNA and environmental RNA to push beyond presence/absence applications

Environmental DNA (eDNA) has unequivocally revolutionized the science of species detection and identification. Ficetola et al. (2008) first demonstrated the potential application of eDNA for the detection of aquatic macroorganisms. The application of genetic tools to detect (and quantify) macroorganismal eDNA has seen subsequent widespread use by researchers and burgeoning adoption by conservation managers (Bruce et al., 2021; Jerde et al., 2013; Jerde, 2019; Sepulveda et al., 2020). For aquatic macroorganisms, the capture and analysis of eDNA represents a cost-effective means to detect rare and/or invasive species and quantify community composition (Cristescu & Hebert, 2018; Jerde, 2019; Jerde et al., 2013; Taberlet et al., 2012), often outperforming traditional approaches (Boivin-Delisle et al., 2021; Sard et al., 2019; Sigsgaard et al., 2015; Spear et al., 2015). More recently, the toolbox of molecular methods to identify organisms from environmental samples has been expanded to include the analysis of environmental RNA (eRNA; Pochon et al., 2017; von Ammon et al., 2019).