Aquatic invasive species (AIS) are a threat to the ecological and economic integrity in freshwater ecosystems. Early detection and monitoring of AIS are essential to contain or eradicate a population in a timely manner and prevent spread to other waters. Physical AIS surveys require considerable effort, money, time, and by then the AIS may already be established. Environmental DNA (eDNA) is organismal DNA that originates from cellular material shed by organisms into the environment which can be detected using molecular methods. This study aims to test and compare different field and lab eDNA methods to determine which combinations maximize detection probability of our target AIS. Field sampling and traditional AIS surveys were conducted at five lakes in Minnesota, USA. Lake characteristics include sizes of large, medium, and small with one being a river system. AIS of interest includes Zebra mussels (Dreissena polymorpha), Spiny water flea (Bythotrephes cederstromii), Rusty crayfish (Faxonius rusticus), and Common carp (Cyprinus carpio). These species were chosen since they have already been established in our selected lake bodies. We compared several different ways of harvesting DNA (volume, filters, sample locations) and molecular biological detection method to see which method performed better. AIS detection using eDNA methods was more sensitive in comparison against traditional AIS detection surveys. The detection probability of eDNA methods by sampling locations (nearshore vs offshore and surface vs benthic) appears to be influenced by species and waterbody types. Our findings will provide guidance and recommendations to natural resource managers who might consider eDNA as an AIS monitoring tool.

Primary Presenter: Anna Totsch, University of Minnesota Duluth (totsc005@umn.edu)

Authors:

Anna C Totsch, University of Minnesota Duluth  (totsc005@umn.edu)

Josh Dumke, Natural Resources Research Institute  (jddumke@d.umn.edu)

Chan Lan Chun, University of Minnesota Duluth  (chun0157@d.umn.edu)