Master of Science (MS), Bowling Green State University, 2015, Biological Sciences

Many of the lake-dwelling fish species of Lake Erie rely on shallow, heavily vegetated bays as spawning grounds to increase offspring probability of survival during early life stages. Multiple complex abiotic and biotic factors can affect mortality especially during early life stages; the loss or absence of suitable habitat is one of these key factors leading to poor recruitment of fish species. Submerged aquatic vegetation (SAV)/macrophyte beds in clearwater systems act as refuges for juvenile fish decreasing mortality from predation while foraging on prey resources. However, it also has been shown that river discharge “plumes” (areas of high turbidity) may act as habitat/refuge for young-of-the-year fishes. The Maumee River and Maumee Bay, once with abundant macrophyte beds, have experienced substantive increases in suspended solids over the last century. Historical introduction of benthivorous feeding carp (especially Cyprinus carpio), sediment pollution from surface runoff in the surrounding watershed and relatively high wave energy further increases the levels of turbidity in bays and decrease the amount of SAV habitat. The potential colonization of western Lake Erie by Grass Carp (Ctenopharyngodon idella) could further reduce the distribution of the SAV that may serve as a crucial habitat for economically and ecologically important Lake Erie fish species. I mapped the distribution of macrophytes in the northern section of Maumee Bay to quantify the utilization of SAV by juvenile fishes and the current distribution of SAV. In summer 2014 I used side scan sonar images processed in Quester Tangent™ computer programs in order to provide this baseline distribution. The 300-hectare mapped area was primarily inhabited by two SAV species, eel grass (Vallisneria americana) and variable pondweed iv (Potamogeton gramineus), and this SAV was distributed over 43.7% of the area (131.2 hectares). The distribution of SAV seemed to be more related to the influx of sediments (open full item for complete abstract)

Committee: Jeff Miner Dr. (Advisor); Patrick Kocovsky Dr. (Committee Member); Dan Wiegman Dr. (Committee Member) Subjects: Aquatic Sciences; Biology; Environmental Management; Wildlife Conservation; Wildlife Management