Tag: ecosystem

Ten Threats: Dead Zones in the Lakes

  • These fishermen at Port Clinton, Ohio, are a few miles away from the dead zone that develops in Lake Erie every summer... so far, most fish can swim away from the dead zone. But the dead zone is affecting the things that live at the bottom of the lake. (Photo by Lester Graham)

One of the Ten Threats to the Great Lakes is nonpoint source pollution. That’s pollution that
doesn’t come from the end of a pipe. It’s oil washed off parking lots by storms, or pesticides and
fertilizers washed from farm fields. Nonpoint source pollution might be part of the reason why
some shallow areas in the Great Lakes are afflicted by so-called dead zones every summer.

Transcript

In another report on the Ten Threats to the Great Lakes series, reporter Lester Graham looks at a
growing problem that has scientists baffled:


One of the Ten Threats to the Great Lakes is nonpoint source pollution. That’s pollution that
doesn’t come from the end of a pipe. It’s oil washed off parking lots by storms, or pesticides and
fertilizers washed from farm fields. Nonpoint source pollution might be part of the reason why
some shallow areas in the Great Lakes are afflicted by so-called dead zones every summer.


Dead zones are places where there’s little or no oxygen. A dead zone develops in Lake Erie
almost every summer. It was once thought that the problem was mostly solved. But, it’s become
worse in recent years.


(sound of moorings creaking)


The Environmental Protection Agency’s research ship, the Lake Guardian, is tied up at a dock at
the Port of Cleveland. Nathan Hawley and his crew are loading gear, getting ready for a five day
cruise to check some equipment that measures a dead zone along the central basin of Lake Erie.


“What I have out here is a series of bottom-resting moorings that are collecting time series data of
currents and water temperature and periodically we have to come out here and clean them off and
we take that opportunity to dump the data as well.”


Hawley is gathering the data for scientists at several universities and the National Oceanic and
Atmospheric Administration’s Great Lakes Environmental Research Lab. The information helps
them measure the behavior of the dead zone that occurs nearly every year in Lake Erie…


“What we’re trying to do this year is get a more comprehensive picture of how big this low-oxygen zone is and how it changes with time over the year.”


One of the scientists who’ll be pouring over the data is Brian Eadie. He’s a senior scientist with
NOAA’s Great Lakes Environmental Research Lab. He says Lake Erie’s dead zone is a place
where most life can’t survive…


“We’re talking about near the bottom where all or most of the oxygen has been consumed so
there’s nothing for animals to breathe down there, fish or smaller animals.”


Lester Graham: “So, those things that can swim out of the way, do and those that can’t…”


Brian Eadie: “Die.”


The dead zone has been around since at least the 1930’s. It got really bad when there was a huge
increase in the amount of nutrients entering the lake. Some of the nutrients came from sewage,
some from farm fertilizers and some from detergents. The nutrients, chiefly phosphorous, fed an
explosion in algae growth. The algae died, dropped to the bottom of the lake and rotted. That
process robbed the bottom of oxygen. Meanwhile, as spring and summer warmed the surface of
Lake Erie, a thermal barrier was created that trapped the oxygen-depleted water on the bottom.


After clean water laws were passed, sewage treatment plants were built, phosphorous was banned
from most detergents, and better methods to remove phosphorous from industrial applications
were put in place.


Phosphorous was reduced to a third of what it had been. But Brian Eadie says since then
something has changed.


“The concentration of nutrients in the central basin the last few years has actually been going up.
We don’t understand why that’s happening.”


Eadie says there are some theories. Wastewater from sewage plants might be meeting pollution
restrictions, but as cities and suburbs grow, there’s just a lot more of it getting discharged. More
volume means more phosphorous.


It could be that tributaries that are watersheds for farmland are seeing increased phosphorous. Or
it could be that the invasive species, zebra mussel, has dramatically altered the ecology of the
lakes. More nutrients might be getting trapped at the bottom, feeding bacteria that use up oxygen
instead of the nutrients getting taken up into the food chain.


Whatever is happening, environmentalists are hopeful that the scientists figure it out soon.


Andy Buchsbaum heads up the Great Lakes office of the National Wildlife Federation. He says
the dead zone in the bottom of the lake affects the entire lake’s productivity.


“If you’re removing the oxygen there, for whatever reason, for any period of time, you’ve
completely thrown that whole system out of balance. It’s all out of whack. It could mean
irreversible and devastating change to the entire ecosystem.”


And Buchsbaum says the central basin of Lake Erie is not the only place where we’re seeing this
low-oxygen problem…


“What makes the dead zone in Lake Erie even more alarming is that we’re seeing similar dead
zones appearing in Saginaw Bay which is on Lake Huron and Green Bay in Lake Michigan.
There, too, scientists don’t know what’s causing the problem. But, they’re already seeing
potentially catastrophic effects on aquatic life there.”


State and federal agencies and several universities are looking at the Lake Erie dead zone to try to
figure out what’s going on there. Once they do… then the battle likely will be getting
government to do what’s necessary to fix the problem.


For the GLRC, this is Lester Graham.

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Ten Threats: The Earliest Invader

  • A bridge for a river... this portion of the Erie Canal crossed the Genesee River via an aqueduct in Rochester, NY. This photo was taken around 1914. (From the collection of the Rochester Public Library Local History Division)

The Ten Threats to the Great Lakes” is looking first at alien invasive species. There are more than 160 non-native species in the Great Lakes basin. If they do environmental or economic harm, they’re called invasive species. There are estimates that invasive species cost the region billions of dollars a year. Different species got here different ways. David Sommerstein tells us how some of the region’s earliest invaders got into the Lakes:

Transcript

We’re bringing you an extensive series on Ten Threats to the Great Lakes. The Great Lakes Radio Consortium’s Lester Graham is guiding us through the reports:


“The Ten Threats to the Great Lakes” is looking first at alien invasive species. There are more than 160 non-native species in the Great Lakes basin. If they do environmental or economic harm, they’re called invasive species. There are estimates that invasive species cost the region billions of dollars a year. Different species got here different ways. David Sommerstein tells us how some of the region’s earliest invaders got into the Lakes:


If the history of invasive species were a movie, it would open like this:


(Sound of banjo)


It’s 1825. Politicians have just ridden the first ship across the newly dug Erie Canal from Buffalo to New York.


(Sound of “The Erie Canal”)


“I’ve got an old mule, and her name is Sal. Fifteen miles on the Erie Canal…”


Chuck O’Neill is an invasive species expert with New York Sea Grant.


“At the canal’s formal opening, Governor DeWitt Clinton dumped a cask of Lake Erie water; he dumped that water into New York Harbor.”


Meanwhile, in Buffalo, a cask of Hudson River water was triumphantly poured into Lake Erie.


“In a movie, that would be the flashback with the impending doom-type music in the background.”


(Sound of ominous music)


It was an engineering and economic milestone, but a danger lurked. For the first time since glaciers carved the landscape twelve thousand years ago, water from the Hudson and water from the Great Lakes mixed.


(Sound of “Dragnet” theme)


Enter the villain: the sea lamprey. It’s a slimy, snake-like parasite in the Atlantic Ocean. It sucks the blood of host fish.


Within a decade after the Erie Canal and its network of feeders opened, the sea lamprey uses the waterways to swim into Lake Ontario. By the 1920’s and 30’s, it squirms into the upper Lakes, bypassing Niagara Falls through the Welland Canal.


What happens next is among the most notorious examples of damage done by an invasive species in the Great Lakes. By the 1950’s, the sea lamprey devastates Lake trout populations in Lake Superior. Mark Gaden is with the Great Lakes Fishery Commission.


“They changed a way of life in the Great Lakes basin, the lampreys. They preyed directly on fish, they drove commercial fisheries out of business, the communities in the areas that were built around the fisheries were impacted severely.”


The sea lamprey wasn’t the only invader that used the canals. Canal barges carried stowaway plants and animals in their hulls and ballast. In the mid-1800’s, the European faucet snail clogged water intakes across the region. The European pea clam, purple loosestrife, marsh foxtail, flowering rush – all used the canal system to enter the Great Lakes.


Chuck O’Neill says the spread of invasive species also tells the tale of human transportation.


“If you look at a map, you can pretty much say there was some kind of a right-of-way – railroad, canal, stageline – that was in those areas just by the vegetation patterns.”


Almost one hundred invasive species came to the Great Lakes this way before 1960. O’Neill says every new arrival had a cascading effect.


“Each time you add in to an ecosystem another organism that can out-compete the native organisms that evolved there, you’re gradually making that ecosystem more and more artificial, less and less stable, much more likely to be invaded by the next invader that comes along.”


(Sound of “Dragnet” theme)


The next one in the Great Lakes just might be the Asian Carp. It’s swimming up the Illinois River, headed toward Lake Michigan. Cameron Davis directs the Alliance for the Great Lakes.


“If this thing gets in, it can cause catastrophic damage to the Great Lakes, ‘cause it eats thirty, forty percent of its body weight in plankton every day, and plankton are the base of the food chain in the Great Lakes.”


The U.S. Army Corps of Engineers has installed an electric barrier in the Chicago Sanitary and Ship Canal that might stop the carp. But as long as the canals around the region remain open for shipping and recreation, it’s likely more invaders may hitch a ride or simply swim into the Great Lakes.


For the GLRC, I’m David Sommerstein.

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Ten Threats: Predicting New Invaders

  • Some say it's only a matter of time before the Asian Carp enters the Great Lakes. (Photo courtesy of the USFWS)

More than 160 kinds of foreign creatures are in the Great Lakes right now, and every few months, a new one finds its way into the Lakes. Those invasive species are considered the number one problem by the experts we surveyed. The outsiders crowd out native species and disrupt the natural food chain, and it’s likely more will be coming. Zach Peterson reports scientists are putting a lot of time and effort into figuring out which new foreign creatures might next invade the Great Lakes:

Transcript

There are new problems for the Great Lakes on the horizon. The Great Lakes Radio Consortium’s Lester Graham is our guide in a series that explains that new invasive species are one of the Ten
Threats to the Great Lakes:


More than 160 kinds of foreign creatures are in the Great Lakes right now, and every few months, a new one finds its way into the Lakes. Those invasive species are considered the number one problem by the experts we surveyed. The outsiders crowd out native species and disrupt the natural food chain, and it’s likely more will be coming. Zach Peterson reports scientists are putting a lot of time and effort into figuring out which new foreign creatures might next invade the Great Lakes:


(Sound of boat motor)


Jim Barta is a charter boat captain just above Lake Erie on the Detroit River. He says over the last decade, zebra mussels and other foreign species have altered the habitat of the walleye he fishes for.


Water that once had a brownish hue is now clear. That’s because Zebra mussels have eaten the algae and plankton that used to cloud the water, and that means Barta’s boat is no longer invisible to the fish he aims to hook.


“You could catch the fish a little closer to the boat because they weren’t as spooked by the boat. They weren’t as afraid of what was taking place.”


So Barta had to rethink his tactics. He now casts his lines out further, and he’s changed lures to continue catching walleye.


But there are other problems the zebra mussel is causing. Eating all the plankton means it’s stealing food at the bottom of the food chain. And, that affects how many fish survive and how much the surviving fish are able to grow.


Anthony Ricciardi is trying to help Barta, and other people who rely on a stable Great Lakes ecosystem. He’s an “invasion biologist” at McGill University in Montreal.


Ricciardi looks for evidence that can predict the next non-native species that might make it’s way into the Great Lakes. He says species that have spread throughout waterways in Europe and Asia are prime candidates to become Great Lakes invaders.


“If the organism has shown itself to be invasive elsewhere, it has the ability to adapt to new habitats, to rapidly increase in small numbers, to dominate ecosystems, or to change them in certain ways that change the rules of exsistence for everything else, and thus can cause a disruption.”


Ricciardi says most aquatic invasive species are transported to North America in the ballast tanks of ocean freighters. Freighters use ballast water to help balance their loads. Some of the foreign species hitchhike in the ballast water or in the sediment in the bottom of the ballasts.


Ships coming from overseas release those foreign species unintentionally when they pump out ballast water in Great Lakes ports. Ricciardi says one of the potential invaders that might pose the next big threat to the Great Lakes is the “killer shrimp.” Like the Zebra Mussel, it’s a native of the Black Sea.


“And it’s earned the name killer shrimp because it attacks invertebrates, all kinds of invertebrates, including some that are bigger than it is. And it takes bites out of them and kills them, but doesn’t necessarily eat them. So, it’s not immediately satiated. It actually feeds in a buffet style: it’ll sample invertebrates, and so it can leave a lot of carcasses around it.”


Ballasts on cargo ships aren’t the only way foreign species can get into the Lakes. Right now, scientists are watching as a giant Asian Carp makes its way toward Lake Michigan. It’s a voracious eater and it grows to a hundred pounds or more.


This non-native fish was introduced into the Mississippi River, when flooding allowed the carp to escape from fish farms in the South. A manmade canal near Chicago connects the Mississippi River system to the Great Lakes.


If it gets past an electric barrier in the canal, it could invade. Many scientists believe it’s just a matter of time. Another invasive, the sea lamprey, also got into the Great Lakes through a manmade canal.


But, researchers don’t usually know when or where an invader will show up. David Reid is a researcher for the Great Lakes Environmental Research Laboratory in Ann Arbor. He says they can’t predict the effect an invader will have when it arrives in its new ecosystem.


“That’s the problem. We don’t know when the next zebra mussel’s going to come in. We don’t know when the next sea lamprey type of organism is going to come in. Generally, if you look at the invasion history of the Great Lakes, you’re seeing about one new organism being reported probably about once every eight months.”


Knowing what the next invader might be could help biologists, fisheries experts, and fishermen know what to do to limit its spread. Invasional biologists hope that their work will help develop the most effective measures to limit harm to the Great Lakes.


For the GLRC, I’m Zach Peterson.

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Bill Aims to Slow Spread of New Invasives

  • A new bill aims to prevent new invasive species from entering our country. (Photo courtesy of USGS)

Many states are asking the federal government to take a new approach in fighting aquatic invasive species. The Great Lakes Radio Consortium’s Shawn Allee has more:

Transcript

Many states are asking the federal government to take a new approach in fighting aquatic invasive species. The Great Lakes Radio Consortium’s Shawn Allee has more.


Currently, federal agencies try to control invasive species after they start disrupting ecosystems in U.S. waterways.


But now the U.S. Senate is considering a measure that calls for testing species for potential harm before they’re allowed into the country. Allegra Cangelosi is with the Northeast Midwest Institute, a regional advocacy group.


“Believe it or not, the door’s been wide open. So anybody in any state, unless the state has a law, can make a decision to bring a new organism to our waters, cultivate it, let it get loose and do whatever.”


If passed, the law would put new restrictions on the pet industry. Federal agencies would decide whether it’s too risky to import a specific fish or other aquativ species. The act would also beef up inspections of ships that might carry invasive pests.


For the GLRC, I’m Shawn Allee.

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Attitudes Changing About Wolves

People’s fear of wolves led to a steady practice of bounties, poisoning, and trapping until the wolf pretty much disappeared from this region by the 1960’s. But a new survey confirms that these old attitudes have changed. A five-year study of people’s opinions about wolves was recently completed. The Great Lakes Radio Consortium’s Mike Simonson has more:

Transcript

People’s fear of wolves led to a steady practice of bounties, poisoning, and trapping until the wolf
pretty much disappeared from this region by the 1960’s. But a new survey confirms that these old
attitudes have changed. A five-year study of people’s opinions about wolves was recently
completed. The Great Lakes Radio Consortium’s Mike Simonson has more:


More than 600 people in Michigan and Wisconsin responded to a survey about wolves. The
survey was done by Northland College Sociology Professor Kevin Schanning. Schanning says
people from both states feel the same way: more than half think wolves should be protected, and
most of the respondents appreciate wolves as a natural part of things:


“When you ask people ‘are wolves the symbol of the beauty and wonder of nature? Do we need
wolves to help manage the eco-system?’ 75 percent to 80 percent of respondents are saying ‘yeah,
we need wolves. They’re a part of our state now and we need to manage them, we need to protect
them.'”


Even so, 62 percent of those surveyed said they worry about wolves being dangerous. And 41
percent are in favor of hunting wolves to manage their populations.


For the GLRC, I’m Mike Simonson.

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Empty Ballast Tanks Still Carrying Critters

  • A scientist collects samples of ballast sediment. (Photo courtesy of NOAA)

A new study finds that ocean-going ships that enter the Great Lakes often carry biological pollution in their ballasts, even when they declare their ballasts are empty. The Great Lakes Radio Consortium’s Lester Graham reports:

Transcript

A new study finds that ocean-going ships that enter the Great Lakes often carry biological pollution in their ballasts, even when they declare their ballasts are empty. The Great Lakes Radio Consortium’s Lester Graham reports:


The study by the University of Michigan and the National Oceanic and Atmospheric Administration looked at ships coming into the Great Lakes from the ocean. Nearly 80-percent of them declared “no ballast on board” and avoided inspections by the Coast Guard.


But several of those ships were tested by the researchers. They found that although the ballast water was pumped out, there were thousands of organisms left behind in the sediment in the bottom of the ships’ ballast. Then, when the ships unloaded at their first stop, they took on Great Lakes ballast water which stirred up the sediment.


And that made it possible for the biological contaminants to be pumped out at the next Great Lakes port.


The authors of the study warn that more restrictions must be placed on how the ships handle ballast water, or the Great Lakes will continue to be invaded by more invasive species such as the zebra mussel, round goby, and 180 other foreign aquatic species that have harmed the Lakes’ ecosystems.


For the GLRC, this is Lester Graham.

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Court Rules Epa Must Regulate Ballast

  • The EPA is being called to put regulations on ballast water discharges. (Photo courtesy of the USGS)

Ballast water discharges from ocean freighters must be regulated by the
U.S. Environmental Protection Agency. That’s the ruling of a California judge.
The Great Lakes Radio Consortium’s Sarah Hulett reports:

Transcript

Ballast water discharges from ocean freighters must be regulated by the U.S. Environmental

Protection Agency. That’s the ruling of a California judge. The Great Lakes Radio Consortium’s

Sarah Hulett reports:


The ruling calls on the EPA to repeal a decades-old exemption for ballast water discharges from the

federal Clean Water Act. Discharges from ships’ ballast tanks have dumped foreign plants and

animals into coastal waters and the Great Lakes. The organisms have wreaked environmental and

economic havoc on native ecosystems.


Jordan Lubetkin is with the National Wildlife Federation.


“By this ruling, ballast water discharge is regulated as a biological pollutant. Ballast water is

treated like a discharge from an industrial facility, or a wastewater treatment facility, and in

this regard it’s no different.”


An EPA spokesman says the agency is reviewing the decision, and its options. The judge has ordered

an April 15th conference for the EPA and the environmental groups that sued to discuss how to move

forward.


For the GLRC, I’m Sarah Hulett.

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Army Corps to Expand Mississippi Locks

The U.S. Army Corps of Engineers is moving ahead with
recommendations to expand locks on the Mississippi River despite
an earlier report that found the Corps’ calculations in making a similar
plan were wrong. The Great Lakes Radio Consortium’s Lester Graham
reports:

Transcript

The U.S. Army Corps of Engineers is moving ahead with recommendations to expand
locks on
the Mississippi River despite an earlier report that found the Corps’ calculations
in making a
similar plan were wrong. The Great Lakes Radio Consortium’s Lester Graham reports:


The Corps of Engineers proposes spending 8.3 billion dollars to expand navigation
locks for
heavier barge traffic and restore the ecosystem of the upper Mississippi River. The
National
Research Council was highly critical of an earlier plan, saying the Corps’
projections of greater
traffic on the river were flawed. In a statement, the Corps says this new plan
balances the need
for economic growth and environmental sustainability.


Environmentalists say it’s still wrong. Melissa Samet is with the group American
Rivers.


“The Corps has done a great disservice to the nation by recommending this project.
We have
other needs. It’s a significant amount of money. The recommendation is based on
unsound
science and unsound economics. And that’s just not the way a federal agency should
be working.
It’s certainly not serving the American people.”


Critics say they expect the Corps of Engineers to lobby Congress hard for funding
the expansion
of the locks and not as hard for the environmental restoration.


For the Great Lakes Radio Consortium, this is Lester Graham.

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Breaking Down Groundwater Pollution

  • While the idea of cleaning up the water with bacteria may be oxymoronic, Michigan State University is saying that it works. (Photo courtesy of the National Science Foundation)

Scientists in the Great Lakes region are seeing good results from a new method that fights groundwater pollution. The Great Lakes Radio Consortium’s Erin Toner has more:

Transcript

Scientists in the Great Lakes region are seeing good results from a new method that fights groundwater pollution. The Great Lakes Radio Consortium’s Erin Toner has more:


Researchers at Michigan State University are using a process that introduces microbial bacteria into contaminated aquifers. Over time, the microbes break down hazardous waste, usually from industrial spills. Before this new technology, the most common cleanup technique was called “air stripping.” That requires groundwater to be pumped to the surface, where toxic chemicals are basically blown out of the water and into the air.


Professor Mike Dybas says the new process doesn’t leave pollution in the ecosystem.


“It’s treatment actually occurring where the pollution is, and it is physically destructive of the contaminant. So at the end of the day, the contaminants are broken down into harmless end products.”


Dybas says the process could be used in any type of industrial or agricultural spill. He says since the microbes move with the water, cleanup could stretch for miles underground.


For the Great Lakes Radio Consortium, I’m Erin Toner.

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Streamside Forests Play Role in Pollution Cleanup

Scientists have known for years that streamside forests help stop certain pollutants from entering the waterway. But new research published in the Proceedings of the National Academy of Sciences shows that those forests have added benefits. The Great Lakes Radio Consortium’s Chris Lehman reports:

Transcript

Scientists have known for years that streamside forests help stop
certain pollutants from entering the waterway. But new research
published in the Proceedings of the National Academy of Sciences
shows that those forests have added benefits. The Great Lakes Radio
Consortium’s Chris Lehman reports:


Steams that flow through forests tend to be wider and slower than those
that flow through meadows or urban areas. Scientists say that creates
an environment that can actually help clean up a polluted waterway.


Bernard Sweeney is the director of the Stroud Water Research Center in
Pennsylvania. He says their research points to a direct relationship
between woods and water.


“You put a forest along a small stream, it creates a more natural and
wider stream channel; that in turn provides more habitat, more
available ecosystem which in turn enables a stream to do more work for
us like processing nitrogen and organic matter.”


Sweeney says government programs that offer incentives to create
natural streamside buffers should do more to specifically encourage
reforestation. He says grass buffers don’t have the same cleansing
effect on waterways.


For the Great Lakes Radio Consortium, I’m Chris Lehman.

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