- [Rob] Coming up on "Great Lakes Now."

- Invasive mussels are eating food that lake whitefish need.

- [Ashley] In areas where they are attached and piled on top of each other you can get 30-40,000 in a square meter.

- [Rob] But something's eating the mussels, too.

- [Harvey] Ironically, an invasive species may be helping to control another invasive species.

- [Rob] And the battle over data centers in Ohio.

- What does this look like for our water quality?

What does this look like for our electricity rates here at home?

(upbeat music) (air whooshes) - [Announcer] This program was brought to you by Richard C. Devereaux Foundation for Energy and Environmental Programs at Detroit PBS, Polk Family Fund, DTE Foundation, and contributions to your PBS station from viewers like you.

Thank you.

- Welcome to "Great Lakes Now," I'm Rob Green.

We're starting the show with an excerpt from "All Too Clear," a documentary that explores the impact of invasive mussels.

The mussels have made the waters of the Great Lakes incredibly clear, and fundamentally changed the food web.

That's having a big impact on lake whitefish.

(air whooshes) (water burbling) - [Narrator] As winter has settled in, the eggs laid by the lake whitefish have been developing, safely hidden in cracks between rocks.

(soft music) Not far away, the parents who laid the eggs are still around, searching for food.

Lake whitefish, also known as atikmeg in many Indigenous communities, can grow to more than six kilograms and live for over 30 years.

(soft mystical music) Their mouths have evolved for digging into the lakebed to feed on animals in the soft sediment.

They often move in schools, grazing the lake bottom.

This feeding behavior, akin to bison grazing grasslands, stirs up nutrients and leaves impressions on the lake floor.

Whitefish probably migrated into the Great Lakes shortly after the lakes formed from melting glaciers about 12,000 years ago.

Their numbers likely once approached 100 million, playing a crucial role in shaping the lake's ecosystems.

But now, their future hangs in the balance.

(water sloshing) As the early spring sun thaws the ice and starts to warm the water, the whitefish eggs begin to hatch.

(whimsical ethereal music) At first, the larvae get nourishment from their egg sacs.

But that won't last long.

And they soon head out in search of tiny aquatic animals called zooplankton.

Life is hard for a baby whitefish.

If they don't find food quickly, they will starve.

Unfortunately, there are very few zooplankton out here for them to eat.

- A 100 years ago, every inch or two they would have found a zooplankton to eat.

Now, they're literally swimming thousands of body lengths in order to get a single meal.

We believe it's directly due to invasive quagga muscles.

(whimsical ethereal music continues) - [Narrator] Historically, whitefish would have hatched into what's known as the spring algae bloom.

As the strengthening sun penetrates into the water, it encourages the growth of algae, turning the water green.

Zooplankton then feed on the plentiful algae and multiply.

The result is an exponential increase in food for baby whitefish, right when they need it to survive.

But now, the algae are being consumed by quadrillions of invasive quagga mussels, each one able to filter more than one liter of water per day.

There are so many mussels, they can filter all of the water in Lake Michigan and Lake Huron every few days.

They've made the offshore waters about three times clearer than they used to be.

- Clear water from an aesthetic perspective, people kind of love that, but from an ecosystem perspective, it really means nothing's there, nothing's growing.

The offshore waters have been described as a biological desert.

(eerie ominous music) - [Narrator] A dive into the offshore waters of much of the Great Lakes is now a descent into a world dominated by quagga mussels.

(eerie ominous music continues) Quagga mussels are the larger cousin of the infamous zebra mussel.

Both species are native to Eastern Europe, and arrived in the ballast water of cargo ships in the late 1980s.

But there are now far more quagga mussels than zebra mussels in the Great Lakes.

Likely because zebra mussels need a hard surface to attach to, where quagga mussels can live pretty much anywhere.

- Quagga mussels, they do like to have a surface to attach to, but they are capable of colonizing soft sediments and that's what's unique about them as opposed to zebra mussels.

(eerie ominous music continues) - [Narrator] Starting at somewhere around 50 meters or a 160 feet, it's often difficult to see the lake bottom for the mussels.

- [Ashley] What we see in those solid carpets, it's probably 20,000 muscles you can get in a square meter.

In areas where they are attached and piled on top of each other you can get 30-40,000 in a square meter.

(eerie ominous music continues) - [Narrator] Anything on the lake bottom out here is a magnet for quagga muscles.

This is especially true of shipwrecks.

Like this one, discovered during the making of this film in Lake Huron.

Resting in over 80 meters of water, it's believed to be the steamship Africa.

Built in 1873, it was lost in a storm in 1895, along with all 11 crew members.

But like many Great Lakes shipwrecks, it's slowly being destroyed by millions of mussels.

To attach themselves to a ship, quagga mussels use sticky little strings called byssal threads.

These threads burrow in to wooden surfaces.

When combined with the acidic waste of the mussels, they speed up the degradation of shipwrecks that would otherwise remain perfectly preserved in these cold, fresh waters.

In recent years, quagga mussels have spread to even the deepest, darkest, coldest depths of the Great Lakes.

- In our annual survey a few years ago, we added more deep sites so that we can say, well, we'll get these sites now and then we can see when mussels reach these sites.

We get the before.

They were already at those sites, at their deepest sites.

So confirmed they are at 200 meter depth.

(somber piano music) (water burbling) - [Narrator] The mussels now cover the bottom of most of the lower Great Lakes.

Only Lake Superior remains mostly untouched, likely because the lake lacks the minerals the mussels need to build their shells.

(somber piano music continues) To see what it was like before the mussels invaded, we must go to Lake Superior.

At first glance, this lake bed might appear lifeless.

But if you look closer, you'll see it's alive with a nearly limitless number of tiny freshwater shrimp called diporeia.

- Diporeia were historically the dominant organism that was on the bottom.

(gentle music) They're small but curled up kinda plump crustaceans.

They look very playful, I think.

They consume detritus on the bottom and organic matter, and they're an important part of cycling of that lower part of the food web.

They themselves are a very high quality food source.

They have high fat content, and they were the preferred and prime prey for a lot of fish species.

- If we were studying whitefish diets in the 1940s, my best guess is that we would be like 95% diporeia.

But now we really have just a couple locations left in the Great Lakes where diporeia even live.

(soft music) - [Narrator] As the mussels advanced, the diaspora disappeared.

Most native fish can't eat the mussels, compounding their profound ecosystem changes.

(gentle pensive music) The loss of food for baby and adult whitefish means that this species is disappearing in the Great Lakes.

The decline has been especially difficult for Indigenous communities whose deep cultural and spiritual relationship with the atikmeg is thousands of years old.

- [Jason] The Anishinaabe took care of this relationship for thousands of years, but now the number of fishers is at an all-time low.

The number of fish harvested is at an all-time low, and that relationship between the people and the fish is really in jeopardy.

(air whooshes) (light music) (air whooshes) - In the near term, things are not looking good for lake whitefish, at least, not in Lakes Michigan and Huron.

But the lakes are changing constantly, and as you'll see in this next story, which we first broadcast in 2020, even decades after invasive mussels arrived in the Great Lakes, the full effect of their presence is still unknown, and the current dominance of mussels may not be permanent.

(air whooshes) - [Narrator] Three of the best known invasive species in the Great Lakes arrived from the same place.

Zebra mussels, quagga mussels, and round gobies all came here from halfway across the world, carried in ballast water by ocean-going freighters.

- We kinda got a transplanted ecosystem from the Black and Caspian Seas.

And actually around 1988, the first zebra mussels were picked up in the St.

Clair River.

- [Narrator] Zebra mussels quickly multiplied and began causing problems by clogging intakes at water treatment plants and power plants.

It was anybody's guess how the ecosystem would respond.

- [David] They come into a system, explode.

And then you have all the different forces of predators, parasites, limiting food supplies, they all come to act on the population.

- [Narrator] But even before native species could adapt to the presence of zebra mussels, a new aquatic invader showed up and changed things again, the quagga mussel.

Harvey Bootsma is a Professor and Associate Dean at the University of Wisconsin, Milwaukee School of Freshwater Sciences.

- Initially, the zebra mussels really took off but they were confined to the edges of the lakes because they live on hard substrate.

But a little bit later, the quagga mussel came in.

And the quagga mussel can live in colder water and it can live on soft bottom, so it spread much more widely than the zebra mussels did.

And it replaced the zebra mussels.

- [Narrator] Bootsma and a team of researchers have discovered something surprising about mussels in Lake Michigan.

- We wanted to see if there was any potential for controlling mussels at least at a small scale in Lake Michigan.

So in 2016, with support from the National Park Service in the Great Lakes Restoration Initiative, we decided to start a mussel removal project.

- [Narrator] The research was done on a rocky reef in Good Harbor Bay between Leland, Michigan, and Sleeping Bear National Lakeshore.

There, a team of volunteer divers spent weeks scraping mussels off of rocks.

- [Harvey] The number of volunteer divers working with us, spent several weeks that summer just going down diving and scraping the mussels off of rocks trying to create a significantly large area that was mussel free.

And then after that, the objective was to monitor that to see what happened to that patch of rock.

- [Narrator] Surprisingly, four years later, there are still almost no mussels in the area.

The research team suspected round gobies might be responsible.

- [Harvey] We think what's happening is the mussel larva or what are called veligers, settle on surfaces where they grow into hard-shelled mussels.

If mussels try to recolonize these rocks, the gobies are eating them before they can grow to any significant size.

- [Narrator] To test that hypothesis, the researchers put in devices called Hester Dendi Traps, which have spaces in them that are big enough for mussels but too small for gobies.

- And sure enough, we're seeing mussels in those traps now.

So it does seem like the gobies are instrumental in keeping the mussels from recolonizing the rocks that we cleared some time ago.

- [Narrator] And taking the mussels away had other effects too.

- Where we remove the mussels, we've also seen a huge drop in other invertebrates because they just don't have anywhere to hide anymore.

So arthropods are a big one.

Another one is isopods.

Fish love to eat them if they can get at them.

There's actually more of them now than there used to be because the mussel beds provide lots of food for them and they provide hiding places for them.

- [Narrator] But once the mussel beds were gone, the fish could gobble up the invertebrates, while the gobies munched on small mussels.

- [Harvey] Ironically, an invasive species, the round goby, it may be helping to control another invasive species, the quagga mussel, by feeding on them.

- [Narrator] Round gobies come from the same place as zebra mussels.

And arrived in the Great Lakes around at the same time.

Gobies can displace native fish partly because of their spawning habits.

- [David] One of their successes is that males guard the nest.

As a result of that, they get a high fertility rate.

And females can spawn I think every two weeks.

And so, they start in May and they spawn all the way to September.

Most fish, they spawn in the spring.

If they get a bad spring, they lose the whole larval fish cohort for that particular time, but not round gobies.

If they're spawning for four months, one of those times, they're gonna hit the perfect storm of good conditions for their survival, and produce a lot of larval round gobies.

And then the second big reason is, quagga and zebra mussels and that's a tremendously huge food supply for them.

- [Narrator] For years, native species ignored the gobies but things have changed.

Today, natives across the basin are adjusting to their presence in surprising ways, and round goby have become a daily special on the Great Lakes menu.

- [David] Once they became abundant, fish walleyes, northern pike and smallmouth bass, smallmouth bass particularly really zeroed in on them.

They're well-known for eating crayfish.

Their diet's really full of crayfish and other benthic fish like darters.

So the gobies were a natural for them.

It took a while but they figured out how to catch 'em.

- [Narrator] Native species like sculpin hide from bass by freezing and blending in.

So that's what the bass are used to.

But gobies have a different way to avoid being eaten, and it took the bass by surprise.

- [David] Because they have this strange behavior that when you scare 'em, they just kinda shoot out in one direction or another.

That's one of the interesting things, that there was definitely a learning curve for these predators in how to catch these round gobies, and they learned how to do it.

- [Narrator] And smallmouth bass aren't the only native predator to start feeding on gobies.

- The other one that has recently been found to eat a lot of round gobies are the lake trout.

We've been seeing some really big changes in their diets as they're shifting from fish like mottled sculpins and the alewives to round gobies.

- Another interesting story is the Lake Erie water snake, which previously was endangered.

And they've made a real comeback because they love to eat gobies as well.

So those are really interesting questions as we're going forward.

What's the new Lake Michigan going to look like?

And are there fish that are able to actually take advantage of this new situation?

- [Narrator] The story of the mussel and goby invasion of the Great Lakes is still unfolding, but the impact has already been huge.

The mussels have filtered the lakes, removing algae and absorbing industrial waste, making the waters clearer.

- [David] They're shifting back to more of the state they were before man interfered and changed everything.

And so, we're certainly getting close to that state.

- [Narrator] What it all means for the lakes is still unknown.

- Lake Michigan is like a moving target right now.

We're trying to understand it.

But the way the lake works is changing while we're trying to understand how the lake works.

(air whooshes) (light music) (air whooshes) - Ohio has become a hotspot for data center development.

These massive facilities are being proposed across the state, mainly in rural communities, and the response from residents has been anything but quiet.

Communities are grappling with questions about water use, pollution, land prices, and who ultimately benefits from these projects.

At the same time, state regulators are considering easing rules for the wastewater that data centers discharge, raising more environmental concerns.

Zaria Johnson reports on the environment for Ideastream Public Media in Cleveland, and she's been closely following the data center debate in Ohio.

This is part of a series of interviews with reporters covering data centers around the Great Lakes.

Zaria, thanks for joining us.

- Thanks for having me.

Happy to be here.

- What's driving the interest?

Why are developers so focused on Ohio right now?

- Yeah, it's partially access to things like large parcels of land resources.

When we think of things like water, land especially, electricity capacity, there are parts of rural Ohio primarily that developers are looking to because that's where they can access those things.

But in talking to experts and conducting these interviews for different stories, another piece of the puzzle is that developers can think that these rural communities might not have the political will or the time or the capacity to organize and push back on these projects.

- And what has the state done to try to attract these developments?

- So there are certain incentives for developers that come to Ohio to implement these data center projects.

There could be tax incentives for developers.

There could also be agreements between utility providers like public water systems to provide certain amounts of water if they have an excess incapacity for those development projects.

- Can you walk me through how the wastewater permits work and what are the proposed changes and what would those changes allow?

- Yeah, so the permits basically outline the amount of wastewater that any sort of industry or utility is allowed to discharge directly into streams that could lead to Lake Erie or the Cuyahoga River.

It basically outlines a cap on the total amount of wastewater that they're allowed to discharge.

And so, the proposed changes at the Ohio EPA is to increase the amount of wastewater that data centers in particular are allowed to discharge and, from a regulatory standpoint, the argument is that this would make the permitting process easier for developers so that they can sort of fast track the process and getting their permits approved.

But environmental advocates are saying that this is basically threatening water quality and the protection of water quality here in Ohio, especially when we think about the Cuyahoga River, its history, Lake Erie's history of pollution, industrial pollution in particular, there's a big concern there.

- Yeah, it seems like the developers have kind of bet that communities won't have the will or the wherewithal to put up much of a fight, but they're losing that bet.

What sorts of concerns are people raising at these meetings?

- Yeah, the biggest are some of the key environmental concerns.

What does this look like for our water quality here in Ohio?

What does this look like for our electricity rates here at home?

What does this mean for the amount of farmland that we have here in the state to actually produce crops?

That's been a big thing that's come up with residents, especially with tariff conversations happening here in the country.

If we're gonna be using a lot of this farmland to put industry on, then we're gonna have to spend more money bringing crops in.

But obviously, a couple big concerns are noise pollution and light pollution from these data centers as well.

There are residents, especially in southwest Ohio, who are nearby Virginia, and they're hearing these stories of data center projects happening elsewhere in the country and the effects of noise pollution and light pollution coming from residents there.

And the concern is, how can we protect ourselves from all of these sort of environmental concerns here in Ohio?

- Zaria, thanks for joining us.

- Thanks for having me.

(air whooshes) (light music) (air whooshes) - Thanks for watching.

For more about any of the stories in this show, visit GreatLakesNow.org.

When you get there, you can follow us on social media and subscribe to our newsletter to get stories and updates from around the region.

(air whooshes) (upbeat music) (air whooshes) - [Announcer] This program was brought to you by Richard C. Devereaux Foundation for Energy and Environmental Programs at Detroit PBS, Polk Family Fund, DTE Foundation, and contributions to your PBS station from viewers like you.

Thank you.

(light piano music)