Monitoring with molecules: validating environmental DNA to survey nature

Session: 15. - Environmental 'omics: New Tools for Aquatic Ecosystem Science and Management

Joanne Littlefair, McGill University, [email protected]
Michael Paterson, IISD-ELA, [email protected]
Michael Rennie, Lakehead University, [email protected]
Vince Palace, IISD-ELA, [email protected]
Melania Cristescu, McGill University, [email protected]

Abstract

The potential for using environmental DNA (eDNA) combined with metabarcoding for large-scale biodiversity assessments is rapidly becoming a reality.  DNA can be isolated from environmental samples, interrogated with universal primers, and sequenced. When matched against reference libraries, this provides an estimate of species distributions. Yet many questions remain as to the creation, persistence and transport of eDNA in natural systems before we can assess whether measurements from eDNA are an accurate reflection of local biodiversity. In flowing water systems (e.g. rivers, lake chains), local detection of species with eDNA may be confounded by the transport of eDNA from upstream. Disentangling these effects (regional versus local diversity) in natural field conditions is reliant on the presence of viable populations which are restricted to one defined area, and monitoring the movement of eDNA released from them downstream. In this talk, I outline experimental work undertaken to examine whether 1) eDNA flows between connected habitats, thus confounding our estimates of species richness with this method, and 2) whether sampling from different zones in the lake (e.g. littoral, pelagic) reflects local species richness. These findings will help us to understand the scales at which eDNA can operate as a biomonitoring tool.

1. Keyword
biodiversity

2. Keyword
monitoring

4. Additional Keyword
environmental DNA

5. Additional Keyword
metabarcoding