GIBRALTAR ISLAND — For two days last week, several journalists gathered at the Ohio Sea Grant/Ohio State University Stone Laboratory research facility on Lake Erie’s tiny Gibraltar Island for an annual overview of a multitude of issues affecting the world’s 11th largest freshwater lake.

And though you can’t talk about Lake Erie without talking about those notorious algal blooms, this year’s gathering hit on many subjects beyond that.

There were discussions about invasive species, wetlands, solar energy, wind energy, climate change, the fishing industry, declining ice cover, birding’s popularity as a recreational activity, and emerging pollution threats, such as those from microplastics and so-called “forever chemicals” known as PFAS.

There was even some talk about how artificial intelligence might be used more as a monitoring tool.

But back to those algal blooms.

Stuart A. Ludsin, an OSU ecology professor, said that many people may not realize that the pledge Michigan, Ohio, and Ontario made in 2015 to reduce phosphorus loading 40 percent over 2008 levels would have some hidden consequences if it is actually achieved.

The goal is to achieve a 40 percent reduction in phosphorus loading into Lake Erie by 2025. Most experts, though, agree that is unlikely because the region still isn’t close to achieving the benchmark it set along the way for a 20 percent reduction by 2020.

But Mr. Ludsin wasn’t delving into the politics of agricultural runoff.

As a scientist, his point was that there are winners and losers in whatever changes are made to water quality, including fewer nutrients.

Once abundant in Lake Erie, lake whitefish have all but disappeared while yellow perch populations have increased.

That, according to Mr. Ludsin, is because peak habitat for lake whitefish requires low nutrients, while peak habitat for yellow perch requires more. A lake that is highly overrun by nutrients and in what scientists call a eutrophic state is best suited for common carp, he said.

In other words, there needs to be some attention paid to the type of lake people want as they try to lower the nutrient level, Mr. Ludsin said. 

He said it’s not just a zero-sum game of trying to eliminate all phosphorus and nitrogen, because the lake needs some nutrients.

“There is no one condition that will support whitefish, perch, and walleye equally while being cleaner for humans,” Mr. Ludsin said.

He referred to the situation as a “wicked management landscape.”

Mr. Ludsin’s remarks stirred memories of discussions held briefly by U.S. and Canadian officials in the mid-1990s after zebra mussels had done such a remarkable job of filtering out the Great Lakes water column that sunlight was penetrating deeper and killing off some of the light-sensitive plants that certain species need for habitat.

There actually had been some discussions about relaxing sewage-discharge regulations back then to help walleye, believe it or not.

“As a researcher, the last thing I want to say is that I want more nutrients and more algal blooms,” Mr. Ludsin said. “The key thing is finding that middle ground. That is the hard part, finding that sweet spot.”

According to the Great Lakes Fishery Commission, lake whitefish are native to Lake Erie and were an important commercial species until the population crashed in the 1950s. The commission also cites over exploitation and invasive species as probable contributors to the decline, and other groups also blame climate change.

Mike McKay, a former Bowling Green State University professor now serving as director of the University of Windsor’s Great Lakes Institute for Environmental Research, talked about his love for searching beneath Great Lakes ice for algae that grows near the surface during the winter.

He’s one of the few researchers who tags along aboard U.S. Coast Guard cutters in the winter to gather ice and water samples during cold weather months.

When people hear about algae, they often think of the blue-green cyanobacteria, such as that growing in western Lake Erie now, that can produce toxins capable of making people sick.

But what’s found beneath ice are hundreds of forms of so-called “good algae,” such as diatoms, that are an important part of a healthy food chain.

“These algae, diatoms, are quite robust,” Mr. McKay said.

He said a lack of understanding of activity beneath ice during the winter has been “a blind spot” of Great Lakes research.

That kind of research is important as climate change reduces ice cover and results in milder winters, Chris Winslow, Ohio Sea Grant and OSU Stone Lab director, said. 

“We’re seeing a different winter for the Great Lakes now,” Mr. Winslow said.

The workshop also featured two University of Toledo researchers, David Kennedy, an associate professor of medicine for UT’s College of Medicine and Life Sciences, and Christine Mayer, an ecology professor at UT’s Lake Erie Center.

Medical experts such as Dr. Kennedy have learned that microcystins, the toxin produced by microcystis and other forms of cyanobacteria that become harmful algal blooms, are more than just liver toxins.

They have become a higher priority to the U.S. Centers for Disease Control and Prevention because of how harmful algal blooms, known as HABs, are on the rise all over the world.

“HABs are becoming more complex and persistent, prolonging the window of time for exposure,” Dr. Kennedy said. “The misnomer is these are liver toxins, but they’re not. They affect almost all organs.”

Dr. Kennedy and Dr. Steven Haller, two UT associate professors of medicine, are leading what’s known as the Great Lakes Aerosol Monitoring Research Study.

It’s a project in collaboration with the University of Michigan and with financial support from the National Institutes of Health to better understand how much toxin gets into the air and where it goes. Another goal is to better understand who’s at risk of inhaling the particles and what, if anything, frequent ingestion over many years, even at low doses, might do to their nasal tracts, their skin, their lungs, their livers, their hearts, and their other organs.

Some 200 volunteers from Lucas, Ottawa, or Sandusky counties are to be tested before, during, and after peak algal bloom season each year for five years.

“I love the lake,” Dr. Kennedy said. “I love the Great Lakes and people ought to be able to enjoy them without health effects.”

Ms. Mayer talked about her ongoing research into grass carp, which have been found in the Sandusky and Maumee rivers.

Grass carp are one of four types of invasive carp formerly known as Asian carp. They are the only invasive carp known to have established breeding populations within the Great Lakes or their tributaries.

She described how UT’s Lake Erie Center has had teams of graduate students pulling grass carp and eggs out of area waterways for several years now. It has been using an electro-shock technique that stuns the fish since 2018.

Fewer fish have been removed this year than in years past, but Ms. Mayer said she’s not claiming victory yet.

The fish are known to spawn in the Fremont area of the Sandusky River and possibly another location.

The spawning locations in the Maumee River have been harder to find, she said.

Mark Rowe and Craig Stow, two scientists from the National Oceanic and Atmospheric Administration’s Great Lakes Environmental Research Laboratory in Ann Arbor, also dispelled some myths about Lake Erie’s proverbial “dead zone” that forms each summer.

Dead zone is the term for a low-oxygen area, a condition known as hypoxia.

Long believed to form in the open water of Lake Erie’s central basin, north of Cleveland, evidence now shows it grows along the Lake Erie shoreline, even in the western basin, before moving out into the center of the lake.

It’s an important distinction because water-treatment plant operators need to make adjustments when they have hypoxic water coming into their plants. Otherwise, they can end up with a condition called “yellow water” when there’s too much manganese, which has happened before to plants in the Cleveland area.

“It’s not the low oxygen that’s a problem, but the other things that go with it,” Mr. Rowe said.

Finished tap water made from hypoxic water turns yellow after reacting with chlorine that’s used in the treatment process.

There’s also no correlation between the size of an algal bloom and the size of a dead zone, Mr. Stow said.

“There’s a tendency to conflate the two,” he said. “It’s just not that neat and tidy.” 

First Published August 31, 2024, 3:25 p.m.