Grand Lake St. Mary’s in Celina is a tranquil spot, but forget about taking a cool dip in the water. The algae that gives the lake its blue-green cast could make you sick. A research team led by BGSU biologists Drs. Michael McKay and George Bullerjahn is studying why this type of algae is growing here and what can be done to encourage the growth of a less toxic form.
“Something is happening in the lake causing the growth of this particular algae,” said Ben Beall, a postdoctoral research associate from Alberta, Canada. “It causes a layer of scum to form on top of the water and even contains toxins, which led to a ban on swimming.”
The experiment is a collaboration between BGSU, the city of Celina and Algaeventure Systems. The company wants to know if a different type of algae called diatoms can be grown. Diatom algae can be used for biofuel and would also help improve fishing on the lake. The researchers are hoping they can manipulate the nutrient content of the water to stimulate diatom growth.
The site is marked with a large sign proclaiming it a “Grand Lake Ecosystem Experiment.” Several large containers with mesh tops float along the lakeshore, each containing a mini-lake environment. Two of them are control samples while the others contain different combinations of nitrates, phosphates and silica. Nitrate and phosphate are found naturally in the lake.
Katrina Thomas, a marine biology junior from St. Mary’s, heard about the project from McKay, who is her advisor. He asked her to join the project after learning she was from the area.
“It’s been a great experience, and I’ve learned a lot about how to use the lab,” Thomas said. “Plus, I never knew there was harmful algae out there that can cause serious damage to your body.”
Thomas is called the “master sampler.” Using a long stick with a cup attached to the end, she stirs the water inside the container before scooping up a sample and transferring it to a clear plastic jar.
She takes the sample across the street to a lab inside the Celina Water Treatment Plant, where she sends it through a microfilter, leaving the nutrients behind. Thomas freezes the filters, adds a chemical to the filtered water and then puts the sample in a refrigerator to be taken back to BGSU.
Once at BGSU, Beall and others analyze the samples for water chemistry. They see how much nutrient is left and if it changed any property of the water. They also look at the type of organisms that have grown and the number of them in the water.
Beall says the first stage of the experiment was successful and showed it is possible to manipulate the lake water. They are still analyzing the data to determine the nutrients’ effect.
Thomas remembers swimming in the lake when she was a child and says it wasn’t so bad. “Now I want to help turn it around to how it used to be.”