ENVIRONMENTAL DNA FOR NEXT GENERATION BIODIVERSITY DETECTION AND FISH DIET ANALYSIS IN TROPICAL FRESH WATERS

Abstract

The use of environmental DNA (eDNA) is an emerging method for the detection and monitoring of freshwater biodiversity, which has yet to be extensively tested in the tropics. Here, two major applications of eDNA are explored in proof-of-concept studies. eDNA in small volumes of water sampled extensively across horizontal and vertical space from two urban freshwater reservoirs reveals signatures for over 500 metazoan species from a metabarcoding analysis using a single universal primer pair, including rare, alien and nuisance species, and many unknown species. eDNA data also enables extensive comparisons of community composition. Metagenomics and metabarcoding analyses of eDNA in the gut contents of fish from the same reservoirs tell of their diverse animal diets, and reveal likely predators of nuisance midges. eDNA thus promises to be a cost-effective and minimally invasive tool for the regular monitoring of the biodiversity in tropical freshwater environments, although further methods development is imperative.