Faculty Mentor(s)

Dr. Brian Bodenbender, Geological and Environmental Sciences

Document Type


Event Date



Cyanobacteria, commonly known as blue-green algae, are freshwater aquatic microorganisms that are important indicators of climate change. They also release microcystins: toxins that can cause sickness, organ failure, or even death in plants, animals and humans. Studies have monitored microcystin presence and concentration in large-scale Cyanobacterial blooms, such as in Lake Erie, but often omit smaller scale instances. This project determines whether or not microcystins are present in the Lake Macatawa Watershed and identifies important conditional factors associated with microcystin presence to conclude if harmful algal blooms like those of Lake Erie are plausible locally. Six sample locations along the shoreline and at river convergence points were sampled twice, with six days between sampling sessions, and analyzed to determine whether cyanobacteria and microcystins were being supplied to the lake or cultivated within it. YSI water quality sonde analyses and resulting correlation coefficients highlighted four conditional factors: temperature, pH, dissolved oxygen (DO), and nitrates. These data were paired with an Envirologix QuantiPlate Kit for detection of Microcystins Enzyme-Linked ImmunoSorbent Assay (ELISA) of the water samples taken at each site. In all, the concentration of microcystins was higher in the first, warmer temperature samples. The relationship between temperature and concentration yielded the highest correlation coefficient value at 0.5986. A weak correlation of 0.3453 was found between pH and concentration. Relationships involving DO and nitrates both yielded extremely weak correlation coefficients. We conclude that microcystins are present within Lake Macatawa. While present, their concentration was not determined to be harmful at any of the sample locations. Outliers within sonde readings supported theories of conditional factors ideal for Cyanobacteria development yet indicate a low likelihood of harmful Cyanobacterial blooms happening within Lake Macatawa.


This research was made possible through support by the Smies Summer Research Fund.