Algae signals lake changes

HOUGHTON — When it comes to climate change, the little shifts are what lead to the big problems.

Algae forms the base of aquatic food webs, often small and easily overlooked. In the Great Lakes, these organisms are changing and researchers don’t know what that will impact.

One such researcher, Andrew Bramburger of the University of Minnesota-Duluth discussed the changes at a talk at Michigan Tech on Thursday.

“We can learn a lot about our lakes and how they’re going to respond to climate change by looking at the algae,” Bramburger said.

Bramburger focuses on studying diatoms, a common type of micro-algae and samples them around the great lakes twice a year at 72 different locations.

“During the time that we’ve been doing this study and basically during the time this monitoring program has been going on, we have this kind of, think of a horror movie, that rising crescendo of scary music,” Bramburger said. “And the rising crescendo of scary music in the Great Lakes is that things have been warming up and this is across the board,” Bramburger said.

This warming is impacting the algae and that’s not something to write off.

He sees the Lake Erie algae blooms as a symptom of deeper changes to the types of algae in the lakes and changes to the growth cycles.

After looking at the types of algae sampled, Bramburger noticed a decrease in cell sizes across all the lakes both within species and across them. With the shift, some organisms slightly higher on the food chain are unable to process the smaller cells changing the food web on the lowest levels.

“But we really don’t know a lot about this yet and this is where our research is going…we also need to understand more of what this is going to do up the food web,” Bramburger said.

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