support for up to four years.The specific goals of this work are to (1) expand capacity in the use of eDNA for detection of beneficial and detrimental species, (2) support ongoing benthic data collection and improve collection of data needed for model development, leading to (3) hydrodynamic model development for the interpretation of eDNA detections and the spread of nuisance aquatic species This CESU will complement ongoing work conducted to describe the biological and chemical conditions leading to overgrowth of Cladophora algae, a common feature in the lower Great Lakes. Previous work (since 2018) has assessed Cladophora abundance at sentinel sites, showing associations between Cladophora biomass, light, nutrients, and invasive dreissenid mussels. These data have been used by Great Lakes Water Quality Agreement Task Teams and various ecosystem modeling groups. The collaborative analyses undertaken through this cooperative agreement would bring innovative tools (e.g., environmental DNA, eDNA), in conjunction with traditional surveys, to improve assessment of native fish communities and help detect new arrivals of potentially invasive species.Current efforts to improve understanding of the interaction of coastal processes on nearshore communities include integrating ecological factors using chemical and biophysical modeling: for example, by modeling nutrient differences between surface waters and those trapped in a benthic boundary layer. Work outlined in this CESU research project will extend data application and modeling concepts to additional Great Lakes, urban coastal regions, and other areas greatly impacted by the abundance of Cladophora growth. Results from these findings will extend the abilities to describe the transport and persistence of nuisance and harmful algae and the importance of habitat, providing critical information for coastal ecosystems throughout the Great Lakes. The data collected from these studies will be useful to develop models of Cladophora growth and relating the role of dreissenid mussels in nutrient cycling and the algal resurgence, as well as supporting new opportunities to improve habitats for native fish communities.A summary of the quality assurance procedures and considerations for each of the project elements should be submitted to the USGS for review and approval before work begins to ensure that the quality of the data to be generated will be suitable for federal and state decision-making.