Future-proofing environmental DNA and trait-based predictions of food webs

Abstract Food webs represent trophic interactions within ecosystems. Matching traits of consumers and resources helps infer trophic interactions and food-web properties. Environmental (e)DNA, commonly used for detecting species occurrences, is rarely used in trait-matching studies because abundance estimates and descriptions of relevant traits are generally missing. We synthesized recent literature on inferences of trophic interactions with eDNA and trait matching to identify challenges and opportunities for coupled eDNA–trait recording schemes. Our case study shows how coupling eDNA and trait data collection improves the ability to characterize greater numbers of food webs across multiple scales ranging from spatiotemporal to trait variation. Future-proofing eDNA data sets requires the collection of new traits or the compilation of existing trait data at spatiotemporal scales that are relevant to detect current and future changes in food webs and ecosystems.