Cleaner water could have negative impacts on certain types of fish in Lake Erie, a study by researchers at Ohio State and other universities found.
Stuart Ludsin, an Ohio State professor of ecology and co-author of the study, calls supervising nutrient levels in Lake Erie a “wicked management problem.” Reducing the nutrients like phosphorus makes the water cleaner and reduces harmful algal blooms and low-oxygen areas called “dead zones.”
That’s good for some fish species, like lake whitefish or walleye. Lake whitefish live on the bottom of the lake and their food supply is affected by low-oxygen dead zones, Ludsin said.
But the study found that reducing nutrients would impact food creation for other species, like yellow perch, a fish that has commercial value and is popular for recreational fishing, Ludsin said. That could impact fisheries that breed and raise the fish.
“It does not appear [that there is] any single level of ecosystem productivity or nutrient loading that's going to maximize the production of all three species simultaneously,” Ludsin said.
Meanwhile, federal guidelines set a goal of reducing nutrients in Lake Erie by 40%, compared to 2008 levels.
Ludsin said there may be a level of nutrients that would be a good compromise and would not significantly hurt any single fishery or impact the lake’s other uses.
“The key thing is figuring what's that level that's palatable by those people who really care about the lake,” Ludsin said.
Ludsin said the study showed that the best way to manage the lake’s health is for those who have a stake in the lake’s wellbeing to come together and have a conversation about nutrient management.
He said those who make decisions about the lake should move toward ecosystem-based fisheries management, where all stakeholder values are considered.
Climate change also must be considered, as it’s expected to exacerbate the water quality issues and harmful algal blooms on the lake, Ludsin said.
