Environmental DNA (eDNA) is being used increasingly for biomonitoring of communities
(e.g., microbes, macroinvertebrates, fish species) across terrestrial and aquatic ecosystems.
Developing methods that combine eDNA approaches with metagenomic barcoded amplicon
sequencing (eDNA-metabarcoding) are now providing a powerful noninvasive and cost-effective
means for comprehensively surveying biodiversity in a wide range of habitats. Invasive species
have a substantial impact on the ecology and economics of the Great Lakes region, and eDNAmetabarcoding methods have recently been applied in monitoring non-native, as well as native,
fish populations in the freshwater systems there. In this research, we validated an eDNAmetabarcoding approach that uses established platforms, the MiFish/MitoFish pipeline, for fish
community monitoring on Lake Michigan. For validation, we compared survey results from our
eDNA-metabarcoding approach to those obtained using traditional surveys (e.g., electrofishing
and seining). We also sampled a closed 180,000-gallon freshwater fish tank system to see how
well our methods characterized a known native fish population that resided in the tank. Finally,
we applied the approach to monitoring invasive and native fish populations in southern Lake
Michigan at a site that is currently undergoing restoration to improve the aquatic habitats.. We
were able to reliably capture the fish community structure of the native fish tank as well as those
of open waters on the lake using our methods. Diversity patterns detected at the restoration site
using our eDNA-metabarcoding approach accurately reflected those of the historical record, which
have taken many years to establish by conventional means. Overall, this study suggests eDNAmetabarcoding is an efficient, credible, and powerful approach to biomonitoring.
Funding
Illinois-Indiana Sea Grant (grant no. NA14OAR4170095)