Assessment of Submerged Aquatic Vegetation in Sandusky Bay

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The US Geological Survey will be assessing the potential effects of Grass Carp on aquatic macrophyte communities in selected small embayments of the Sandusky River and upper Sandusky Bay where there is evidence of Grass Carp presence. This work supports an existing CESU with the University of Toledo to assess spawning potential of Grass Carp in the Sandusky River, where spawning has been documented (Chapman et al. 2013, J. Great Lakes Res. 39:547-554). Aquatic macrophytes are important rearing areas for young Grass Carp, hence knowing where macrophyte beds exist and their species composition are critical to understanding this species’ ecology in Lake Erie, which will further inform potential control measures. Aquatic macrophyte beds will be assessed either remotely with side-oriented or down-oriented SONAR or using mechanical methods, whichever is appropriate for a particular macrophyte bed and the time of year sampling occurs. When sonar-based sampling is conducted, commercially-available software applications will be used to classify areas of potentially different species. Samples of vegetation will be collected from several fixed locations within each sampling area to ground-truth and validate vegetation classifications. Vegetation samples will be collected to calculate relative abundances and community composition of vegetation communities. The research assistant will be responsible for conducting vegetation surveys (sonar, manual, and ground-truthing), coordinating research with USGS researchers and potentially other agency and university collaborators, analyzing all vegetation data, and assisting with processing ichthyoplankton net and light trap samples under an existing Cooperative Agreement with the University of Toledo.

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