Areal Abundance Assessment of Aquatic Angiosperms with Aquanauts, Acoustics, and an Acute Angled Appliance

Aquatic vascular plants, like Eurasian Water-Milfoil (Myriophyllum spicatum), play many important roles in freshwater ecosystems. They provide important habitat for fish and macroinvertebrate populations and act as regulators of environmental phenomena like water turbidity and wave action. Fish habitat in the Milwaukee Estuary is characterized by localized areas of developed habitat with large expanses of little cover. Due to this, there is room for improvement of local water bird forage and recreational fishing. Characterization of the plant populations and their distributions is of key interest for potential management strategies. The survey was done throughout July and August of 2017. Shallow areas of the estuary (less than 8 meters deep) were traversed with small boat and populations found visually and through use of traditional sonar. If a population boat sized or larger was found, the center would be approximated and the plants rake sampled from it. The sampling locations were marked with GPS. There were three unique areas in the Milwaukee Estuary: Veterans Park, the Summerfest Lagoon, and Southshore. Veterans Park was characterized by sparsely distributed groups of Potamogeton richardsonii. The Summerfest lagoon was characterized by dense plant beds and a population mainly of Elodia. canadensis and M. spicatum. Southshore was most diverse in terms of plant species, four of them had high abundances (E. canadensis, M. Spicatum, Potamogeton crispus, and Potamogeton spp.). With this information, Southshore and the Summerfest Grounds seem to be good potential locations for habitat development.The results from these surveys provide a baseline that can be used for future projects in the estuary. With a rough map, new studies could be done with higher resolution techniques, such as dive transects/quadrats or the use of echo-sounding equipment. This could result in better management, meaning a potentially more productive ecosystem