Environmental DNA Detection of Invasive Species in the Great Lakes Commercial Bait Trade

In the Great Lakes region over 180 non-native species have been introduced, many posing risks to native biodiversity and ecosystem functioning.  One potential pathway for introduction is the commercial bait trade as unknowing or unconcerned anglers commonly dump unused bait into water bodies.  Previous surveillance studies have used visual inspection in retail bait stores which can be time consuming and requires a trained individual that can rapidly and accurately identify cryptic species.  Environmental DNA (eDNA) surveillance, a molecular monitoring tool that has been employed in aquatic environments, has the ability to detect individuals at low abundances easier and more efficiently.  In 2012, we surveyed and collected samples from over 400 retail bait stores throughout the Great Lakes basin including stores in Illinois, Indiana, Michigan, Ohio, and Wisconsin. We then applied eDNA monitoring techniques to screen these samples for multiple non-native species, including bighead carp Hypophthalmichthys nobilis and silver carp H. molitrix.  To date, we have detected non-native species DNA at multiple commercial stores.  This assessment is helping to gauge the potential for invasive species to be spread through the bait trade and will aid in future management and control of invasive species.