MUSKEGON, Mich. — In a drop of freshwater from Lake Michigan lives algae and zooplankton, the foundation of the Great Lakes food chain, essential to the functioning of its multi-billion dollar fishery.
Record lows in ice coverage this winter and continued warming temperatures, however, may throw these populations into imbalance.
"The Great Lakes, they're so immense," said Al Steinman, a professor at the GVSU Robert B. Annis Water Resources Institute. "My main concern is people get complacent. They think, 'My God, we have water to last forever."
The reality, Steinman says: "We can screw it up." From invasive zebra mussels that blanket the beds of the Great Lakes to toxic algal blooms that can close beaches, "in many cases, we [already] have."
But not all algae is bad, as the photosynthetic organism produces oxygen, playing a pivotal role in supporting life on earth.
"Not the Amazon trees. They're doing it in part." Steinman said. "Algae are making this life habitable for human beings."
When historically high winter temperatures keep ice from forming over the Great Lakes, though, algae can rapidly grow in the spring and summer, with blooms even appearing in the fall.
While most are harmless, blue-green algae can be dangerous to humans, killing fish and fouling up shorelines with debilitating toxins.
"What are most susceptible are these drowned river mouth lakes," said Steinman, listing off Lake Macatawa and Muskegon Lake as potential sites for increased algal blooms, "problematic from a recreational perspective."
Another foundational part of the aquatic food chain, zooplankton consume algae but tend to stay away from blue-green algae, due to a difficult to digest mucus, thus leading to a lack of nutrients that works its way up the web.
"There's going to be transfer problems," Steinman said.
In a warming world, some realities cannot be reversed; Steinman says the beauty and biodiversity of these lakes are always worth protecting, perhaps by starting with a little less fertilizer on the front lawn.
"It behooves us all," Steinman said. "I would hope that other people would have that same passion about caring for our water resources."
