Lake Erie in Peril: Four Looming Threats to our Most Valuable Resource

NOAA

Compared to the other Great Lakes, Lake Erie is the least of them all. While it has more surface area than Lake Ontario, it's the shallowest and contains the least water. We could pour three Lake Eries into Lake Ontario, and 25 into Lake Superior. Even its shape is unremarkable. Lake Huron from above looks like a wolf's head. Lake Erie resembles a man's slipper.

But Lake Erie is ours. It defines us. Our city and county takes its name from it. Our history was formed around it, and our region's economy and livelihood depends on it. In a sense, we are defined by Lake Erie.

And it's in trouble.

Wherever we have gone in the world, we humans have drastically altered the natural landscape and its delicate ecosystems. We tear down hills, fill in wetlands, cut down forests. We dig holes in the ground and extract metal, oil, gas. We bring with us disease and animals and plants. We consume. We waste.

Ever since we humans settled on Lake Erie and its tributaries, we dumped garbage into the water and on its banks. Native Americans left shell middens at their campsites. Early Euro-American sailors and settlers littered the lake bottom with the wrecks of their wooden sailing ships.

And as technology and industry advanced, so did our waste.

There have been low points. There was so much industrial and agricultural waste in the water, Lake Erie was considered "dead" by some in the 1960s. In 1969, the Cuyohoga River in Cleveland – which empties into Lake Erie – contained so many pollutants, it caught fire. Presque Isle Bay not long ago was afflicted with toxic waste and raw sewage.

We are again at a crossroads. Massive algae blooms are cropping up. Invasive species threaten the habitat of native fish. A survey recently found the highest concentrations of waterborne microplastics recorded in the world in Lake Erie. And climate change promises to severely alter our region's weather, transforming the lake in ways we can't imagine.

This is our lake.

Last summer, the Flagship Niagara took on a group of scientists and college students and spent several days on Lakes Superior, Huron, and Erie, pulling a trawl behind her. Dubbed the "Manta" for its two distinctive wings that kept it afloat and made it resemble the ray of the same name, the trawl was skimming the surface water with a net. Its prey wasn't fish; instead, the Manta was after plastic.

"The first sample we took on Superior," said Dr. Sherri "Sam" Mason, a chemistry professor at SUNY Fredonia, and one of the scientists on the Niagara performing the plastic survey. "We caught a big piece of seaweed with big hunks of plastic on it. But the vast majority of what we were finding was really, really small."

So small, in fact, it was not visible to the naked eye. When the Manta was hauled inboard and the net inspected, everyone aboard the ship would crowd around as the contents were revealed. But there wasn't much to be seen. A cigarette wrapper, once. A piece of Styrofoam. Crew and students alike were disappointed.

"I remember having a conversation with Captain Wes [Heersson]," said Mason. "And he said, 'I hear you're not catching anything,' and I said, 'No, I don't think that's true.'

"It's hard when you're looking at this mass, you see fish and bugs and seaweed and plankton, and there are no big things of plastic and you think, you're not catching anything. But I knew that there was more to the story. Once we got back to the lab, we started getting those counts."

What Mason and her team found in Lake Erie were large concentrations of microplastic – plastic pieces less than one millimeter in size. They found one sample with 450,000 plastic particles per square kilometer in Lake Erie, about twice as many particles as found in any other sample from the ocean...or anywhere else in the world, for that matter. The Pacific Ocean may get all the press for its floating island of plastic – the "Great Garbage Patch" – but Lake Erie's waters have the highest concentration of plastic in the world.

"For the biggest counts we got," said Mason, "we'd sit down and ask ourselves, 'okay, this wasn't right around the time we did a swim call, was it? Or right after a deck shower?' We made sure the galley didn't release any gray water or anything like that, because the counts seemed so high."

Where are all these particles coming from? Mason and her team aren't sure, but there are two likely explanations: the particles are from larger pieces that have been degraded over time, or they've been released directly into the lake.

"We think, because of what we found – these perfectly little spherical beads of plastic," said Mason, "we suspect they're being released directly as these little microbeads."

The suspected culprit? Common household consumer products, like facial cleansers, toothpaste, and hand cleansers, which are, yes, often suffused with tiny plastic beads. These tiny bits are not cleansed by the wastewater treatment process and are released into the lake.

That's right, you may be brushing your teeth with plastic.

The results surprised the scientists. That's because most of the plastic particles found in the ocean were between 1 and 5 millimeters in size, and, because the majority of the particles had migrated into the ocean from the Great Lakes and other inland areas, they expected to find that a majority of plastic in the lakes would be larger than 5 millimeters. They expected to find that, as plastic moved towards the ocean, it would break down on the journey into ever-smaller pieces. Instead, they found the opposite. Smaller particles upstream.

So why is this? One reason is dispersal. The ocean is so big that, once the particles reach the ocean, they disperse and aren't easily counted. Another reason is that they could be "going away along the path," as Mason put it.

"As they go through the water, we know they pick up these bio films," said Mason, "these little colonies of organisms that live on top of the plastic." If the build-up of bio film is great enough, it could cause the particles to sink to the lake bottom, where they might be consumed by mussels or other benthic organisms. Or they could be mistaken for natural food by fish in the lakes, and consumed.

Either way, it's very possible that microplastic is entering the food chain. And that's the greatest danger these bits of invisible plastic pose.

"The smaller the plastic, the easier it mimics natural food," said Dr. Lorena Rios-Mendoza, another scientist that participated in last summer's sampling, and a professor of chemistry at University of Wisconsin at Superior. Again, while scientists aren't sure about the effects of the plastic on lake fauna, Rios speculated that ingested plastic could be negatively impacting fish nutrition.

"If the fish eat this plastic, what's going on with the endocrine system in the fish?" asked Rios. "What happens if the fish dies? Are the same components released into the environment? What if the fish are eaten?"

Rios also confirmed that these bits of plastic absorb industrial pollutants, such as PCBs, a deadly toxin that adversely affect plant, animal, and human life. Now banned, PCBs – or Polychlorinated biphenyl – was a common industrial substance, but has links to liver and breast cancer, and lymphoma.

If the microplastic did enter the food system, being eaten by mussels or fish, then these toxins likely would be concentrated and passed along the food chain, altering the very DNA of the organisms that consumed it, and doing molecular-level damage that might last generations.

But the biggest problem with microplastics is this: "Plastic isn't biodegradable," said Rios. "It lasts a thousand years."

During the Lake Erie region's industrial heyday, dumping of sewage and industrial waste into the lake was unregulated and commonplace. As a result, Lake Erie suffered from regular algae blooms – thick coatings of toxic algae that covered swaths of the lake and made much of it uninhabitable for fish and other lake life. The algae fed off of the wastes in the water, sucked oxygen out of the water as it decayed, and emitted toxic substances that were harmful to human health and the environment. The algae also drove boaters off the water and swimmers from the beaches, severely impacting tourism on the lake.

Lake Erie was so bad that it was written off by many environmentalists as "biologically dead," and the pollution in the Great Lakes was so severe that it prompted the United States and Canada to sign a treaty in 1972 agreeing to protect the water quality in the area.

Since then, the lakes' condition has improved vastly, and large algae blooms became rare.

That is, until recently.

Each spring from 2008 to 2010, bad algae blooms occurred, only to be topped by the 2011 bloom, which broke all the records for size. That year, the bloom covered more than 2,000 square miles of the lake surface – nearly twice the area of Erie County – and grew to a thickness of over 10 inches in certain places. The bloom was so large, it was easily seen from space, and NASA satellite photos show sickly green tendrils starting at the lake's west end stretching east past Cleveland on the south bank and Port Stanley on the north.

The 2011 bloom consisted of the algae, Microcystis, which not only created dead zones in the lake's center, devoid of oxygen and nutrients, but also secreted a liver toxin into the lake waters.

This spring, a team of researchers led by Anna Michalak, a professor of Environmental Earth System Science at Stanford University's Carnegie Institution for Science, released a paper examining the record-setting bloom. "The two main things we were trying to do relative to the record breaking algae bloom in 2011," said Michalak, "was to understand the causes, and whether the factors responsible are consistent with what we expect so see in the future."

According to Michalak, the group considered a variety of factors: agricultural land use, such as crop choice, in the area; regional agricultural practices surrounding applying fertilizer; precipitation patterns; and the position the lake wind and currents. What they found was that all these factors – except for land use – came into play for the 2011 event. "And all of these factors," said Michalak, "including land use, are expected to continue into the future."

That is, that record-setting bloom was far from a freakish or unique event. Barring change, it will probably happen again.

Essentially what happened is that unusually large and frequent spring storms in May and early June of 2011 washed fertilizer off of fields and into the lake. The phosphates in the fertilizer fed algae, which bloomed early and quickly because of the lake's unseasonably warm water. Wind was low, and currents relatively stagnant, too, which normally churn the water, discouraging algae from growing.

A factor in the chain of events that led to the bloom is that farmers typically apply fertilizer to the top of soil, avoiding tilling and help preserve nutrients in the soil. This method of application makes the fertilizer more susceptible to erosion during large storms. Still, explained Michalak, we shouldn't point fingers at farmers.

"It's in nobody's interest for fertilizer to run off fields," she said. "Farmers aren't interested in fertilizing algae, they're interested in fertilizing crops."

Really, if there's a culprit in the 2011 algae bloom – and the others in recent years – it's climate change, which, according to climate models, is responsible for the increase in early storms' frequency and intensity. And, according to Michalak, that will likely only continue. "We're not expecting a shift in the total amount of precipitation," she said, "just in the timing and intensity."

Rising temperatures also means that Lake Erie's waters will likely continue to trend warmer in the spring, too. "There are some recent papers suggesting wind speeds on Lake Erie are likely to decrease as a result of climate change," said Michalak, "or have already been observed to decrease." Wind pushes water, which creates current. With decreasing wind and current, Lake Erie's spring waters will be more suitable for the growth of algae.

Still, it's important to note that it took a variety of factors to create the bloom. Farming practices alone didn't cause the algae bloom, nor was climate change solely responsible. "We need to recognize the complexity of these systems," said Michalak. "The key is to look at the system from multiple different angles."

In some ways, that complexity offers some hope for the future. By, say, working with farmers to come up with better application of fertilizer, we might be able to cut down on the severity of algae blooms. Michalak emphasized that better short-term weather prediction would greatly aid farmers, who could avoid applying fertilizer right before severe storms.

"It's a very complex problem," said Michalak. "The only reason we were able to do these analyses was because we looked at all these factors together. We need to get used to thinking about these events as a variety of causes. Wind and precipitation and agricultural practices and so on worked together to create a really unusual event."

If you perform a Google search on "Asian carp," the YouTube videos that return have names like "Silent Invaders," "Asian Carp Attack!," and "Weird, True, and Freaky."

The images from the videos match the names; nearly all of them are shot from a motorboat and feature dozens – sometimes hundreds – of enormous fish leaping out of the water. In one, boaters duck as fish fly into their boat. Another shows a couple sitting at the back of a boat hunting the fish with bows – but one carp flies out of the water, collides with the woman, and breaks her jaw. Another shows a university rowing team caught in a frenzy of leaping fish. And then there's the "Peoria Carp Hunters," who don spiked football helmets and armor and wield machetes as they water ski through carp-infested waters, hacking at fish that leap into their path.

The scenes from these videos may look bizarre, but the fish's jumping habit is also deadly. Some fish weigh as much as 40 pounds, and can seriously injure boaters motoring at 20 or 30 miles per hour.

But the ecological threat these carp pose to Lake Erie dwarfs the danger they pose to boaters.

The Asian carp actually comprises two species: silver carp and bighead carp. Originally introduced by fish farmers to clean algae from their holding tanks, Asian carp escaped into the Mississippi River Basin when the tanks overflowed from floods, and, being fast-growing and aggressive, they outcompeted native fish. Their population  and range has since exploded, and they now infest the Illinois, Ohio, and Missouri Rivers, along with dozens of smaller tributaries and lesser rivers.

And they're knocking on the doors of the Great Lakes.

The fish, for example, that inhabit the Illinois River are separated from Lake Michigan by a solitary canal – the Chicago Sanitary and Ship Canal – which connects the Illinois to the Chicago River and the lake. That canal is protected by electric fish barrier, but many critics – environmentalists, local officials, anglers – say the canal needs to be sealed off in order to keep the fish out of the Great Lakes.

Asian carp DNA has been found in Lake Erie, but it's not known whether that represents a reproducing population, or just a straggler or kill remnants from anglers or natural predators.

"If those species establish reproducing populations in Lake Erie," warned John Stark, the Ohio Freshwater Conservation Director of the Nature Conservancy, "the most damaging thing from an ecosystem standpoint is that they'll consume large quantities of the 'good' algae, the base of the entire food web of Lake Erie.

"If they take out this basic building block, it'll have a ripple effect, and will likely knock down the native fish, walleye, yellow perch."

In some ways, though, the concern and attention paid to Asian carp ignores the impact invasive species already in Lake Erie have on the native ecosystem.

Zebra mussels, for example, were introduced from the ballast water of the international shipping visiting the Great Lakes. When those ships emptied their ballast water, they also emptied mussels and their larvae into the lake water.  "They're a real challenge," said Stark of the mussels. "They're so easily spread."

Zebra mussels are a nuisance to humans. "They clog the water mains of municipalities," said vice president of the Save Our Native Species (SONS) of Lake Erie, Ed Kissel. "They clog the boat intakes of motors."

While zebra mussels have been accredited with "cleaning" Lake Erie's water by many laypeople, that "cleansing" ability is actually representative of the damage the pose to the lake's ecosystem. Amy Jo Smith, executive director of Environment Erie explained: "They don't clean the water – they clear the water of plankton and other small organisms that are major food sources for native fish."

And while Stark noted that zebra mussels are experiencing a kind of "dieback" – a shrinking of the population, usually from natural causes – especially in places like the Ohio River, another exotic mussel, the quagga mussel, is stepping in to replace the retreating zebra mussel population.

There's also the round goby, a small fish that eats the eggs of native fish, and the spiny water flea, a crustacean the size of zooplankton whose spiny tail, when ingested by larval fish, kills the fish. In short, there are over 150 established invasive species that have been introduced to Lake Erie since the early 1800s, all of which to a greater or lesser degree have impacted the lake habitat.

"Invasive species have the ability to completely change an ecosystem," said Smith, "from the types of fish, invertebrates, and plant species, to the flow rates of streams and creation of barriers within the ecosystem."

As example, Smith cited phragmities, a kind of common reed and nonnative to Lake Erie, which can  create "massive barriers and completely close off a lagoon or pond from other systems to wildlife that needs the water for drinking or spawning."

Lake Erie is especially vulnerable to invasive species. With its shallow depth, it's the warmest and most hospitable to new flora and fauna. Combined with human activity – international shipping, the building of canals, or simply taking your boat from lake to another – this means that further spread of invasive species to Lake Erie seems almost inevitable.

And then there's climate change, likely the most influential and devastating environmental effect that will shape the future of Lake Erie. And yet we can't be certain what kind of changes warming temperatures will bring. After all, the climate is a complex system, and global warming might affect our regional weather patterns in unusual and unexpected ways.

For one, global warming will likely mean we'll see an increase in lake-effect snow.

At least, that's the finding of University of Michigan Professor of Atmospheric Science Alison Steiner and her team, who used computer modeling to determine what effect a diminished ice cover and warmer surface-water temperatures might have on lake-effect snow.

"We used computer modeling to understand controlling factors, and to understand lake ice," said Steiner, "and how removing it would affect lake-effect snow."

In short, they found that the pattern of ice, or the lack of it, determines where, and how much, lake-effect snow takes place. Removing the ice, they found, increases the reach, severity, and amount of lake-effect snow. That's because ice traps lake water. Remove the ice, and the wind and weather scoops up more water to dump on the banks of Lake Erie in the form of snow.

But increased lake-effect snow is not the only suspected change to the region's weather patterns as a result of climate change. Steiner is part of a group of scientists funded by the National Science Federation to study the effects of climate-change-induced extreme events on the Great Lakes water quality – that same grant also includes Professor Michalak's algae-bloom study – and their research has shown that precipitation patterns for the lakes are changing.

"Our research is showing more precipitation happening early in the spring," said Steiner. "Precipitation then drops down in the summer and increases again in the fall." In short, the total amount of precipitation doesn't seem to be changing, but when and how it precipitates has.

And timing is everything. As already seen, early storms combined with warmer temperatures contributes to the spread and virulence of algae blooms. But those early storms also have other adverse effects on the Great Lakes ecosystem. As the Nature Conservancy's John Stark noted, several native fish species spawn upriver in Great Lakes tributaries; early severe storms are known to push fish eggs off reeds.

"A year ago, we had extremely low water," added Stark, "which is another manifestation of climate change. There was an early dry part of the year last year in western Ohio and fish had trouble getting up the Maumee because it was low. You can have that in any of the tributaries."

Climate change also contributes to drought and low lake water levels. Drought is another kind of extreme natural event – the kind of event that will become more frequent and intense as a result of climate change. The early torrential rains of 2011 were mirrored a year later by an extremely dry spring, and the water level of Lake Erie dropped to historically low levels.

And, to come full circle, diminished ice cover in the winter contributes to low lake water levels. That water sucked up by winter winds that fuels lake-effect snow is largely lost to the lake. Lake evaporation increases without its ice cover.

The climate of the Great Lakes region is a complex system interdependent on a number of factors. Increasing temperatures are upsetting the balance, increasing the frequency of extreme weather events and severely stressing an ecosystem that evolved around a more stable environment. Tributaries might dry to trickles, or be flooded by unusual spring floods, endangering the fish that spawn there. Lake water temperatures might fluctuate more rapidly than normal, leading to large fish kills – like what happened this spring. And warming lake temperatures combined with dead zones might deprive native fish of the cooler zones they need to survive the summer. And that's not even considering the effects that these changing weather patterns will have on the fishing industry and regional agriculture.

What the long-term effects of climate change are, few can say. There are dire predictions – the drying up of Lake Erie, say, or the extinction of the human species – but even what we can currently experience and see is cause for alarm.

It all sounds catastrophic – microplastic, algae blooms, invasive species, climate change – and it is. That list doesn't include the very real problem of industrial pollution, the heavy metals and other chemicals still present in the lake from the region's industrial legacy.

But there's hope.

For starters, the lake water and ecosystem is better off now than it was 50 years ago. In the 1960s the lake was filthy and nearly barren. But when the United States and Canada signed the Great Lakes Water Quality Agreement and Congress passed the Clean Water Act in the early 1970s, effective regulation cut down on industrial pollution.

There's also government infrastructure that exists to help protect the lakes' natural ecosystems. The U.S.-Canada International Joint Commission (IJC), for one, oversees bodies of water on the border – including the Great Lakes – and one of its missions is to preserve water quality. The IJC's Lake Erie Ecosystem Priority (LEEP) program is working to understand and curb harmful algae blooms, for example. The federal government, too, is working to improve Lake Erie environmental health. A number of agencies are working together on the Great Lakes Restoration Initiative to clean up toxics, protect and restore wetlands, and combat invasive species. And there's also the Ohio and Pennsylvania Sea Grant programs that work to fund research and education and promote stewardship of the Great Lakes.

And then there are the myriad of citizens' groups and nonprofit organizations working on preservation. Nationally, one group working on lake ecology is the Nature Conservancy through its Great Lakes Project. Here in Erie, for example, two such groups are the SONS of Lake Erie, a group of anglers looking to protect the lake's fisheries, and Environment Erie, a nonprofit working on restoration and revitalization of the regional environment. And these are just three of hundreds of organizations working to make the Great Lakes healthier. That is, there are whole numbers of real people concerned about Lake Erie and who are working to make it better.

Erie itself has experienced the positive effects of government agencies working with citizens' groups to improve Great Lakes ecology. When Presque Isle Bay was identified as an "Area of Concern," it prompted infrastructure investment in our wastewater treatment system, contributing to the cleanup of the bay.

Likewise much of the lake's problems do have solutions. Or, at least, there are ways to mitigate existing problems.

To reduce microplastics in the lake, for example, we could work with beauty product and toothpaste manufacturers to limit or end their use of plastic in their products. To curb algae blooms, it's possible to work with farmers on better timing for applying fertilizer to soils. We could make sure regulations overseeing the discharge of ballast water of international shipping to the Great Lakes have teeth, preventing further importation of exotic species in the bellies of ocean-going freighters.  And we could close off Chicago's Sanitary and Ship Canal to create a real barrier between the Illinois River and the Great Lakes, making it difficult for Asian carp to find its way into the lakes basin.

There are even ways to mitigate the effects of climate change.

"We constrain river systems and wetland so they can't take up the effects of extreme events," said the Nature Conservancy's John Stark. "Those systems originated over thousands of years, they were sort of put together to do that. They basically had the ability to handle those extremes." Restoring connectivity to river systems, removing dams, restoring wetlands, said Stark, would give the lake's ecosystem the ability to react to torrential spring storms or periods of drought.

Environment Erie's Jo Ann Smith refers to "climate adaptation." "That includes creating climate-savvy projects," she said, "such as using models and tools available to choose components of our projects that will be able to handle the current environment and one in the future. For example, when designing a planting project, use species that are suited for today's climate and for the increased temperatures over the next decade."

Smith's group will even be hosting a symposium in the fall on "climate adaptation." "We're targeting community organizations and public officials," she said, "to help those officials and grassroots groups learn how to make their projects climate change savvy." The symposium is the result of a partnership between Environment Erie and Pennsylvania Sea grant.

And there's mitigation. Cutting down on the use of fossil fuels. Protecting the rainforest, say, or reforesting lands, to promote carbon sequestration. Massive investment in alternative energy sources and energy efficiency.

These are what's possible. None of it is easy. Especially curbing global warming – that has to be on a global scale, and a significant portion of the nation's politicians and citizens still think it's a hoax, despite the mounting evidence right before their eyes.

And it may even be too late.

But the bottom line is this: Lake Erie's health depends on you. Me. On all of us. We can reduce our consumption, stop using plastic, wash our boat bottoms after boating on the lake, and pressure our elected officials into taking action.

After all, it's our lake.

Jay Stevens can be contacted at Jay@ErieReader.com, and you can follow him on Twitter @Snevets_Yaj.