Date Approved
12-13-2025
Graduate Degree Type
Thesis
Degree Name
Biology (M.S.)
Degree Program
Biology
First Advisor
Mark Luttenton
Second Advisor
Alan Steinman
Third Advisor
Matthew Cooper
Fourth Advisor
Daniel Mays
Academic Year
2025/2026
Abstract
Eurasian watermilfoil (Myriophyllum spicatum, EWM) is an invasive aquatic plant that can impact the ecology and recreational value of lakes. Lake managers typically control EWM with herbicides but interest in non-chemical alternatives such as burlap benthic barriers has grown. In summer 2022, the Grand Traverse Band of Ottawa and Chippewa Indians and the Lake Leelanau Lake Association deployed burlap barriers as part of an effort to control EWM. The purpose of this study was to observe if there were changes in water quality, macrophyte, macroinvertebrate and fish communities, in response to barrier deployment. During the summers of 2022 – 2024 I monitored three treatment locations that received barriers in 2022 and two reference locations that did not. My data indicated that soluble reactive phosphorus was generally < 0.005 mg/L above and below the barriers and at reference locations for my entire study. Nitrate concentrations at two treatment locations were similar to reference locations throughout and decreased below the barriers after initial deployment, while concentrations at the remaining treatment location was consistently higher above and below barriers. However, ammonia concentrations were significantly higher below barrier (0.21 ± 0.05 mg l -1 ) compared to above barriers (0.07 ± 0.02 mg l -1 ) at all treatment locations and compared to concentrations at reference locations. After barrier deployment, EWM declined and macrophyte composition became similar to reference locations as native plants began recolonizing the area. Macroinvertebrate abundance and community composition did change due to change in substrate but were similar when comparing like substrates. Significant changes in abundance and composition were dictated due to changes in zebra mussels and Chironomidae abundances. Fish communities remained similar after barrier installation, with differences noted specifically between pre-barrier habitat that was comprised of almost 100% EWM, and other habitat types. However, these changes in fish composition could not be directly linked to the use of burlap barriers. Though variation did occur in water nutrient concentrations above and below the barrier, and within biological communities, lasting effects on the lake bottom environment due to burlap barriers are unlikely, as the barrier deteriorates and nutrient concentrations and biological communities begin returning to pre-barrier status.
ScholarWorks Citation
Briem, Anna Kathrine, "Managing Eurasian Watermilfoil with Burlap Barriers: Response of Biological Communities and Nutrients" (2025). Masters Theses. 1172.
https://scholarworks.gvsu.edu/theses/1172
