Date of Award

Summer 2020

Degree Type




First Advisor

Dr. Nicholas Troendle


In 2014, the invasive Oriental weather loach was found in the Prairie Creek wetland at Midewin National Tallgrass Prairie. While little is known about the Oriental weather loach and its impact on freshwater ecosystems it has become a widespread invasive species. Being the first to investigate the impact of the Oriental weather loach on the Grant Creek and Prairie Creek watersheds at Midewin National Tallgrass Prairie, we set traps for specimens from early June till late July in both watersheds. Each loach that was caught was euthanized and dissected in order to understand what the Oriental weather loaches are eating and how they are likely impacting the ecosystem. Of the 138 total Oriental weather loaches caught, none were found in the Grant Creek watershed or the creek of the Prairie Creek watershed. The stomach contents contained a wide variety of prey items but Alonella, Nonbiting midge larvae, insect eggs, and Simocephalus were the most abundant. The Oriental weather loach’s diet was similar to that of native Bluegill, Central mudminnows, and tadpoles, which could suggest that they are competing with these native species. The results of this study suggest that Oriental weather loaches may be negatively impacting the freshwater ecosystem of the Prairie Creek wetland at Midewin National Tallgrass Prairie. Future studies are needed to better understand the severity of the Oriental weather loaches impact at Midewin National Tallgrass Prairie and other freshwater ecosystems.