Surveying environmental DNA (eDNA) from marine environments

DNA isolated and characterised from a variety of substrates including sediments and water is collectively referred to as environmental DNA (eDNA). DNA is shed into the environment from a variety of biological secretory... [ view full abstract ]

DNA isolated and characterised from a variety of substrates including sediments and water is collectively referred to as environmental DNA (eDNA). DNA is shed into the environment from a variety of biological secretory processes leaving genetic footprint that acts lens into species composition. When combined with next generation sequencing (NGS) and metabarcoding, eDNA can provide a wealth of information for studies of biodiversity, food web dynamics, diet analysis, invasive species monitoring and disturbance gradients. Metabarcoding eDNA has become feasible only because it is now possible to simultaneously sequence millions of copies of DNA from complex multi-species environmental samples.

The research in the trace and environmental DNA (TrEnD) laboratory has been developing a variety of eDNA workflows to investigate how best to conduct eDNA work in a variety of applications. This presentation will explore how (i) eDNA correlates with video technologies (ii) how eDNA signatures vary with substrate selection  (iii) how eDNA survey vary temporally and spatially and (iv) the use of eDNA in measuring disturbance gradients. Lastly this presentation will also highlights that sensitivity of eDNA metabarcoding also comes with risks - false positive/negatives and contamination. A number of recommendations will be discussed from sample collection to data analysis that will maximise the potential of eDNA metabarcoding as a tool in marine biomonitoring.