Tag: zebra mussels

Combating Inland Invasives

  • Eurasian Watermilfoil is one of the non-native species that has invaded inland lakes. (Photo courtesy of National Park Service)

Invasive plants, fish and other creatures are threatening many inland lakes. Environmentalists and property owners are trying to stop the spread…before the invaders dramatically alter the smaller bodies of water. The Great Lakes Radio Consortium’s Ann-Elise Henzl reports:

Transcript

Invasive plants, fish and other creatures are threatening many inland
lakes. Evironmentalists and property owners are trying to stop the
spread…before the invaders dramatically alter the smaller bodies of
water. The Great Lakes Radio Consortium’s Ann-Elise Henzl reports:


It’s strange to think that plants and animals from Europe, Asia and Africa
are living in small lakes in the Midwest. Boaters have taken invaders
there…after picking them up in the Great Lakes.


The big lakes are home to more than 160 aquatic invasive species,
including Eurasian Watermilfoil. The stringy plant grows in thick
clusters that get up to 12 feet tall.


“I have seen lakes where if you fell out of the boat in these massive
weeds and you weren’t wearing a life jacket, I don’t care how good a
swimmer you are, you would sink. You can not struggle your way
through these thick entanglements of weeds.”


Ted Ritter leads an effort to reduce aquatic invasive species…in
Wisconsin’s Vilas County.


(Sound of pontoon motor)


On one afternoon he takes his pontoon boat on a lake that had an
infestation of Eurasian Watermilfoil.


“It is a very aggressive plant and it has no natural predators to control its
growth, it grows up to two inches a day.”


When Eurasian Watermilfoil finds conditions it likes, it takes over
quickly. A piece as small as two inches can break off, and float away to
create a new plant.


Eurasian Watermilfoil is widespread in northern Michigan… northern
Wisconsin and other places. It’s one of dozens of aquatic invasive
species on the move in the region.


One of the worst invaders is zebra mussels. They can ravage a lake’s
ecosystem.


(Sound of motor boat)


So far, they’ve made it to just one lake in northern Wisconsin. Mike
Preul with the Lake Superior Chippewa scuba dives there, to count the
mussels. Three years ago, he found 7 adults per square meter. This year,
he counted more than 14-hundred:


“They’re still increasing. What they’ve seen in other systems is that just
like with any other exotic species they’ll come in, the population will
explode, they’ll kind of eat themselves out of house and home, and then
they’ll come down to a level and reach a steady state.”


No method has been discovered to get rid of zebra mussels, but there are
ways to control some invaders.


Herbicides can be used to kill Eurasian Watermilfoil, and some property
owners chip in to buy aquatic insects to kill the plants.


Les Schramm did that on his local lake:


“As the larvae hatches it burrows into the stem of the Eurasian
Watermilfoil and sort of eats out the center vascular part, and it falls over
and dies.”


People fighting aquatic invasive species say it’s like fighting weeds in a
garden — the work never stops and it can be expensive.


Ted Ritter of Vilas County says it costs thousands of dollars to treat a
lake once. So, often people do nothing.


Ritter says that can hurt the environment. He says it can also threaten the
economy, in areas like northern Wisconsin that rely on tourism.


Ritter says the invaders can reduce the appeal of a lake. He mentions a
plant called “curly leaf pondweed.” When it dies in the middle of
summer, it creates algae blooms that look like slimy green pillows:


“When people arrive at resorts and they look out and they see that very
unappealing lake they say ‘I’m not staying here,’ and they go somewhere
else. When realtors bring prospective buyers out to look at a property,
people get out of their car and they go right to the lake and they say ‘oh
my, I’m not even interested in looking at the house. This lake is
horrible.'”


Because it’s so difficult to control invasive species, Ritter and others
fighting the invaders focus on prevention.


Local volunteers and workers from the Wisconsin Department of Natural
Resources spend hours at boat landings. They urge people to clean their
boats, trailers, and fishing gear thoroughly when going from lake to lake,
that can keep unwanted plants and creatures from traveling along.


For the GLRC, I’m Ann-Elise Henzl.

Related Links

States Seek to Tighten Ballast Water Laws

Port officials are wary about new state regulations intended to keep invasive species out of the Great Lakes. Several states are working on laws that would tighten restrictions on ballast water in foreign ships. The Great Lakes Radio Consortium’s Bob Kelleher reports:

Transcript

Port officials are wary about new state regulations intended to keep
invasive species out of the Great Lakes. Several states are working on
laws that would tighten restrictions on ballast water in foreign ships. The
Great Lakes Radio Consortiums Bob Kelleher reports:


Proponents hope to keep creatures like zebra mussels from getting
established in the Great Lakes. The non-native plants and animals arrive
in ship ballast water, carried from overseas ports.


Adolf Ojard is the Duluth Seaway Port Director. He says a state-by-state
approach to regulate ballast water is the wrong approach.


“We’re not the only area that is dealing with invasive species. Every
harbor and estuary around the world has a similar concern. It needs to be
dealt with on an international and world level, so that it can be a level
playing field for everybody out there that is involved in transportation.”


Michigan has passed new rules with stiff fines for ships with untreated
ballast water. Wisconsin and Indiana are expected to consider similar
rules; and Minnesota’s Attorney General says he’ll propose the
regulations this spring.


For the GLRC, I’m Bob Kelleher.

Related Links

Ten Threats: Botulism Kills Beach Birds

  • Interns for Presque Isle State Park in Erie, Pennsylvania walk along a Lake Erie beach picking up dead birds. (Photo by Lester Graham)

Researchers are beginning to understand what’s killing thousands of
Great Lakes shorebirds. It might be part of a larger problem indirectly
caused by humans. The Great Lakes Radio Consortium’s Lester Graham
reports:

Transcript

We’ve been bringing you reports from the series, ‘Ten Threats to the Great Lakes’ which is now looking at the threat to beaches. Our guide through the series is Lester Graham. He reports that scientists are beginning to understand what’s killing thousands of Great Lakes shorebirds. It might be part of a larger problem indirectly caused by humans.


Researchers are beginning to understand what’s killing thousands of
Great Lakes shorebirds. It might be part of a larger problem indirectly
caused by humans. The Great Lakes Radio Consortium’s Lester Graham
reports:


Along parts of Lake Erie, Lake Ontario, and Lake Huron, large numbers
of dead birds and fish are washing up on shore. If they’re left there, the
disease that killed them can be passed on to other wildlife. That’s why
park officials such as Mike Mumau at Presque Isle State Park at Erie,
Pennsylvania ask their staff to watch out for the dead carcasses.


“Our interns do a great job. They’re the eyes of the staff that are out. So,
there’s probably three to four days a week that they’re out on the
beaches, checking to see if they have anything.”


Since 1998, untold numbers of fish and sometimes hundreds of dead
birds a year have washed up on just these eight miles of Lake Erie beach.


Eventually, researchers figured out the problem: type “E” botulism. It
slowly paralyzes the birds until the respiratory system shuts down. Most
of them don’t make it that long. They get so weak they can’t hold their
heads up out of the water and they drown.


(Sounds of walking and shovel)


Leslie Jones and her fellow interns are headed out to an area to pick up
some dead seagulls on the beach.


“When we’re out here doing migratory bird studies, we might see some
and then we pick them up as soon as possible. A lot of times, we get
radioed from different people like lifeguards and they have us come out
and pick them up so that the disease doesn’t spread throughout the rest of
the ecosystem.”


They find five dead birds rotting on the beach. They bury the maggots
because they could carry the botulism toxin and other birds might eat the
maggots. They shovel the bird carcass into a black plastic garbage bag.


“If they’re very fresh, this one, obviously not very fresh, but, if we get a
fresh one, we actually freeze them and they’re sent off to be tested
botulism, but, something like this we’ll just bag up until we can get them
incinerated to get rid of all the disease.”


The fresh carcasses are shipped to the National Wildlife Health Center in
Madison, Wisconsin.


There, Grace McLaughlin is among the researchers who are beginning to
put the puzzle together.

Here’s what they think is happening. The invasive species zebra mussels
and quagga mussels create huge mussel beds that begin a complicated
biological phenomenon. Organic matter collects there, and then decays. It
lowers the oxygen level in the immediate area of the mussel beds. Type
“E” botulism spores occur naturally, but when the oxygen level goes
down, they begin reproducing like crazy. The waste they produce is the
toxin.


“That toxin will accumulate in the organic matter as well as in the water
in the immediate vicinity of the mussel beds. As the mussels do their
filter feeding, they will accumulate the toxin in their tissue. They are not
susceptible to the toxin. However, when the fish start coming down
there and eating the mussels, they become intoxicated, lose their ability
to swim properly and become easy prey for the birds that come in.”


The fish that feeds on the mussels the most is another invasive species,
the round goby. Researchers made the connection when they noticed the
botulism started being a problem shortly after round gobies arrived in big
numbers.


The type “E” botulism toxin has killed tens-of-thousands of birds such as
cormorants, terns, loons, ducks, and seagulls.


Back at Presque Isle State Park, Mike Mumau says it’s terrible to see so
many birds die.


“We just do our best on our end to stop the botulism cycle. When we
can, provide samples, and also, keep it a positive recreational experience
for all our visitors. They don’t want to see birds decomposing and
rotting out on the beaches, so we’re pretty diligent with that.”


Researchers say that’s about the best that can be done. Since ocean-
going vessels brought zebra mussels, quagga mussels, and round gobies
to the Great Lakes, all three of the invasive species have flourished. It
will likely be a long time before we’ll ever begin to understand the full
extent of the damage to the native wildlife of the lakes.


For the GLRC, this is Lester Graham.

Related Links

Ten Threats: Hidden Costs of Invasives

  • Foreign ships like this one from Cypress are known as "Salties" around the Great Lakes. These ships are responsible for bringing aquatic invasive species into the Lakes, and we're all paying a price. (Photo by Mark Brush)

In looking at these threats to the Great Lakes, almost everyone we surveyed agreed the worst threat was alien invasive species. Shipping goods in and out of the Great Lakes has helped build the major cities on the Lakes. But shipping from foreign ports has brought in unwanted pests. Zebra mussels are probably the most infamous, but there are more than 160 aquatic species that have invaded the Lakes and changed them, almost always for the worse. So why can’t we keep them out?

Transcript

Today we begin an extensive series called “Ten Threats to the Great Lakes.” The Great Lakes Radio Consortium’s Lester Graham is our guide through this series:


In looking at these threats to the Great Lakes, almost everyone we surveyed agreed the worst threat was alien invasive species. Shipping goods in and out of the Great Lakes has helped build the major cities on the Lakes. But shipping from foreign ports has brought in unwanted pests. Zebra mussels are probably the most infamous, but there are more than 160 aquatic species that have invaded the Lakes and changed them, almost always for the worse. So why can’t we keep them out?


Well, let’s say I import widgets.


(Sound of widgets dropping into a cup)


I’ve been getting widgets from somewhere in Asia, but I found out I could get widgets from an eastern European company for a dollar-a-widget cheaper. The factory there can ship them directly to my warehouse in Great Lakes City, USA by ship across the Atlantic and into the Great Lakes.


Pretty good deal. I get good widgets, the shipping costs are cheaper, my profits go up, and it means cheaper widgets at the retail level. Everybody wins, right?


Well, the ship that brought the widgets also brought an alien invasive species that stowed away in the ship’s ballast. A critter that’s native to eastern European waters is now wreaking havoc on the Great Lakes ecosystem.


Aquatic alien invasive species that have invaded the Great Lakes now cost the economy an estimated five billion dollars a year. Five billion dollars of what’s considered biological pollution.


So, who’s paying the price?


Cameron Davis is with the environmental group Alliance for the Great Lakes.


“Unfortunately, in most instances, who pays for those hiddens costs are you and me. We pay for our water agencies to have to clean zebra mussels out of their pipes, we pay our agencies through taxes to have to keep Asian Carp out of the Chicago River, we pay through our taxes in any number of ways to try to fight these invaders.”


So right now, taxpayers and utility ratepayers – even those who never bought a widget and never will – are paying the price. Davis says that’s just not right.


“One of the things we need to do is make sure that those ships are paying full cost for everything that they bring, not just the widgets, but the stowaways like the zebra mussels, things like that that they have on board.”


So, why target the ships?


Dennis Schornack chairs the U.S. Sector of the International Joint Commission. The IJC is a bi-national agency that monitors a water quality agreement between the U.S. and Canada. Schornack says that’s the way it usually works: the polluters pay.


“The cost of the impact of these unwanted creatures is something that’s not baked into the price charged for the widgets. So, somewhere that external cost needs to be captured back into the price. The ship owners themselves are the likely target to pay for this through a permitting fee which, of course, they will pass on to their customers, the people who made the widgets.”


So all of us who buy widgets end up paying a little more, but paying permits and fees could cost shippers more than they can afford. George Kuper is with the Council of Great Lakes Industries. Kuper says he understands the first impulse is to make the shippers pay.


“The problem with that, of course, is the shippers were already close to non-economic as a method of transportation, which puts us right up against an environmental challenge because shipping is by far the most environmentally un-intrusive method of moving large amounts of materials.”


Kuper says using other methods of transportation such as trains or trucks to move that cargo from East Coast ports might burn more fuel and cause more pollution.


But of all the shipping on the Great Lakes, only six percent of the tonnage is carried on ocean-going vessels. The rest is transported on Great Lakes carriers that never leave the lakes and don’t bring in new invasives. So, the question is this: is that six percent of cargo worth the damage that aquatic invasive species cost each year.


Many experts say there is a fairly simple answer to all of this. Technology is available for cargo ships to eliminate invasives from their ballast tanks. Requiring those ships to use that technology would likely add some to the cost of every widget, but supporters of the idea say it would greatly reduce the environmental cost to the Lakes.


For the GLRC, this is Lester Graham.

Related Links

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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LOOKING AHEAD TO 2005’s GREAT LAKES ISSUES

  • The Great Lakes is the largest group of freshwater lakes in the world. Preservation and usage of the Lakes is a hot issue for 2005. (Photo courtesy of michigan.gov)

This coming year will likely see some major policy decisions regarding the Great Lakes. Because the lakes stretch out along eight states in the U.S. and two provinces in Canada, getting all the governments to agree on issues is a long and sometimes trying process. But… those involved think 2005 will be the year that some real progress on Great Lakes issues will be made. The Great Lakes Radio Consortium’s Lester Graham recently talked with the Chair of the U.S. Section of the International Joint Commission, Dennis Schornack. The IJC deals with disputes and advises the U.S. and Canadian governments on issues regarding the Great Lakes:

Transcript

This coming year likely will see some major policy decisions regarding the Great Lakes. Because the Lakes stretch out along eight states in the U.S. and two provinces in Canada, getting all the governments to agree on issues is a long and sometimes trying process. But those involved think 2005 will be the year that some real progress on Great Lakes issues will be made. The Great Lakes Radio Consortium’s Lester Graham recently talked with the chair of the U.S. Section of the International Joint Commission, Dennis Schornack. The IJC deals with disputes and advises the U.S. and Canadian governments on issues regarding the Great Lakes:


The International Joint Commission and the Government Accountability Office both have been critical of the U.S. government for not finding clear leadership on Great Lakes issues. Different agencies sometimes find their efforts overlap or conflict with others. At times, it seems there’s no organized effort to restore the health of the Great Lakes. Dennis Schornack says he thinks things were starting to get better because recently appointed U.S. Environmental Protection Agency Administrator Mike Leavitt took a real interest in the Great Lakes. But now Leavitt is leaving to become the new Health and Human Services chief.


“It’s going to be hard to beat the enthusiasm of Mike Leavitt. He spent literally about fifty percent of his time as EPA Administrator in the Great Lakes throughout. He was everywhere this past summer. But it does fall to the new administrator, whomever he or she may be; but in the meantime, the governors and mayors are proceeding forward on the priorities that they set over a year ago, and fleshing those out into very tight kinds of recommendations.”


Countless studies and reports on the Great Lakes point out one of the biggest threats to the lakes is invasive species. Those are foreign critters such as zebra mussels and round gobies that hitchhike in the ballast water of cargo ships, or are introduced unintentionally. Often the invasives damage the native fish, plants, and ecosystems of the Great Lakes. Nothing has been done to effectively stop importing the invasives, and some have gone so far as to suggest that the St. Lawrence Seaway connecting the Great Lakes to the Atlantic Ocean should be closed. The IJC’s Dennis Schornack says he’s hopeful that we’ll soon see laws that will do more to help prevent invasive species from getting into the Lakes.


“In the United States, at least, there is pending legislation that has been pending for over two years now called the National Aquatic Invasive Species Act. This legislation is overdue. It’s time for Congress to act on it. And in the ’05 legislative Congressional year, it’s time for them to act. And that’s the place where the standards get set, the authority gets established and where all of the rubber really hits the road. Now, that’s just in the United States. Bi-nationally, because the Great Lakes are a shared resource, the IJC, that I’m the chair of the U.S. section, has continued to advocate cooperation and collaboration between the two countries in terms of at least setting a common standard, a common rule, common regulation on the Great Lakes. Because, obviously, setting it on one side of the boundary line doesn’t do any good if the other side doesn’t follow.”


Another issue that’s recieved a lot of attention in the Great Lakes region recently is water diversion. A document called Annex 2001 tackles the issue of how much water can be used or withdrawn from the Lakes. The various state governors and province premiers put together draft agreements for public comment. Schornack says there’s been a huge response, and a lot of it hasn’t been positive.


“They recieved, I think, over ten-thousand public comments. And there is differing viewpoint, a growing difference between the view taken in Canada and the view taken in the United States on this effort. Canada, the province of Ontario, has come out and point-blank opposed the existing documents. There are concerns in Canada that this is just some kind of a ruse to somehow allow diversions of the Great Lakes waters to occur. I’m not part of that viewpoint, to tell you the truth. What’s being done right now and what will happen in 2005 is that the comments are being digested, we’ll see new draft documents come out from the governors and premiers and hopefully begin the process making those agreements stick.”


Schornack says 2005 will also see some important reports on the economic costs of invasive species. Studies on the logistics of shipping, cargo ship traffic and alternative freight haulers and design plans that look at the total cost of shipping – including the infrastructure costs and the environmental damage caused by invasive species. It should be an interesting year for the Great Lake if Congress moves on key issues, and then finds money to make the Great Lakes more sound.


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

Related Links

Smaller Fish After Alewife Die-Off

  • Alewife (Alosa pseudoharengus). The fish is not common in Lakes Superior or Erie. (Image courtesy of Wisconsin SeaGrant)

This past year, the size of salmon in some Great Lakes
is getting smaller because their main food source is dying off in some
areas of the lakes. The Great Lakes Radio Consortium’s Lester Graham
reports:

Transcript

This past year, the size of salmon in some Great Lakes is getting smaller because
their main food
source is dying off in some areas of the lakes. The Great Lakes Radio Consortium’s
Lester
Graham reports:


In the 1960’s, fish and game officials introduced Pacific salmon such as chinook,
coho and
steelhead to control the invasive species alewife. That’s a small fish that moved
in from the
Atlantic. The salmon are popular fishing. But since the alewives are not native…
they’re
especially susceptible to quick weather changes. And fisheries managers suspect
competition
with zebra mussels for food also affects alewives. Recently, alewife populations
have crashed in
some places. Jim Dexter is with the Michigan Department of Natural Resources…


“The primary reason that there are not alewives in Lake Huron and you get
fluctuations in Lake
Michigan is related more to the climate. You know, now, zebra mussels are tied into
that, into the
equation at some point but not probably to the affect that the climate is having on
those.”


So, without as many alewives, salmon don’t have as much to eat… and they’re smaller
than usual.
Fisheries managers say the effect is probably temporary.


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

Related Links

Comments Sought on Navigation Study

The U.S. Army Corps of Engineers and the Canadian Department of Transportation are studying the navigational system in the Great Lakes and along the Saint Lawrence River. As the Great Lakes Radio Consortium’s Celeste Headlee reports, the groups are holding public hearings on the issue this summer:

Transcript

The U.S. Army Corps of Engineers and the Canadian Department of
Transportation are studying the navigational system in the Great Lakes and along the
Saint Lawrence River. As the Great Lakes Radio Consortium’s Celeste Headlee reports,
the groups are holding public hearings on the issue this summer:


The study will evaluate current conditions in the Great Lakes and determine what is
required to maintain the navigational routes at the existing size and capacity.


Tim Eder is the director of Water Resources for National Wildlife
Federation. He says any plans for Great Lakes navigation must address current problems
of invasive species and habitat destruction, not make them worse. Eder says only a
handful of ships come in from foreign ports on a daily basis…


“But each ship brings with it the risk of another invasive species and right now, our
fishery in the Great Lakes region is teetering on the brink of collapse because of zebra
mussels, because of sea lampreys, because of Asian carp that are knocking on the door
trying to get into the Great Lakes… most of which, not all, but most of which come in the
ballast tanks of ships from foreign ports.”


The public hearings are being held at various locations through July 14th.


For the Great Lakes Radio Consortium, I’m Celeste Headlee.

Related Links

Invasives Altering Great Lakes Food Web

For decades, aquatic invaders have been plaguing the Great Lakes. They’ve changed the way the ecosystems work and affected the balance of life in the lakes. Most of them didn’t just wander in. They hitchhiked a ride into the Lakes in the ballast water of ships from across the Atlantic. The Great Lakes Radio Consortium’s Carolyn Gramling reports… now the combination of these invasive species is causing changes that concern scientists:

Transcript

For decades, aquatic invaders have been plaguing the Great Lakes. They’ve changed the way the
ecosystems work and affected the balance of life in the lakes. Most of them didn’t just wander in.
They’ve hitchhiked a ride into the Lakes in the ballast water of ships from across the Atlantic. The
Great Lakes Radio Consortium’s Carolyn Gramling reports…now the combination of these invasive
species is causing changes that concern scientists:

Zebra mussels were one of those species that hitched a ride in the ballast of a ship. They first
appeared in the Lakes in the mid-1980s. Zebras and their cousins the quagga mussels compete for
food needed by aquatic animals native to the lakes.

Researchers say now these mussels are part of another problem. They’re changing the food web.

The food web is made up of organisms that feed on each other. Usually it’s a chain of small, even
microscopic species that are food for ever larger species. Zebra mussels are near the bottom. For
their food, they filter large volumes of water containing contaminant-laden algae and sediment. In
the process they ingest PCBs and other toxins.

Gene Kim is a researcher in the Ohio State University’s Aquatic Ecology Laboratory. He says that
zebra mussels and a non-native fish called the round goby have helped to form a new food chain
within Lake Erie – a chain that can connect harmful chemicals buried in lake mud to humans.

“A lot of the exotic species, these alien species, have incorporated themselves into the Lake Erie
food web, and there’s a lot of ramifications, in terms of, will they change the cycling of historical
contaminants that right now are in the sediments, but they could be redirected back into sport fish
and eventually, humans.”

Zebra mussels have few natural predators in North America, and they reproduce rapidly. As a
result, they’ve been wiping out native mussels and clogging up water intake pipes in the lake. So
the arrival of the round goby, which likes to eat zebra mussels, would seem to be good news.
Instead, it has proven to be a double-edged sword.

Roy Stein is a professor in Ohio State’s Aquatic Ecology Laboratory. He says the PCBs and other
contaminants, once held captive in the sediment at the bottom of Lake Erie are taken up by zebra
mussels, and then the zebras are eaten by the round goby.

“And then, interestingly enough, round gobies are important prey for smallmouth bass that people
eat, and all of a sudden we have the opportunity for those PCBs that were stored in the sediments
to come up through the food chain and influence humans.”

So, Stein says, those contaminants that were trapped in the sediment now have a pathway up the
food chain.

Gene Kim’s research is confirming the link between smallmouth bass and round gobies. He says
it’s clear round gobies like to eat zebra mussels. But it’s less clear whether bass prefer to eat gobies
over other prey fish. So, Kim devised a laboratory behavior study that let the smallmouth bass
choose between several types of prey, including gobies, emerald shiners, and crayfish.

“The interesting thing is that they actually target these emerald shiners more often than round
gobies, but emerald shiners have superior escape abilities.”

Round gobies, Kim says, just don’t swim away as fast – and so get eaten the most. He adds that
when compared with the stomach contents of Lake Erie bass, this laboratory result is borne out –
more gobies were consumed than any other prey.

Roy Stein says that this puts the system in a kind of double jeopardy.

“The combination of PCBs plus being a slow prey causes perhaps more PCBs to move up through
the food web than otherwise might be the case.”

PCBs have been linked to cancer and birth defects in humans – and they’re not the only
contaminants in the lake.

Other research indicates this new food chain might be helping other pollutants in the sediment find
their way to humans. For example, another Ohio State study finds methylmercury is also getting
into the food web through invasive species. Methylmercury in fish can cause neurological problems
for expectant mothers and other health problems.

Doug Haffner is the Canada Research Chair for Great Lakes Environmental Health and a professor
of Biological Sciences at the University of Windsor. He agrees a zebra mussel – round goby –
smallmouth bass food chain has created a route that exposes humans to harmful chemicals in lake
sediment.

“For a chemical to be of concern to us, it has to be biologically available, it has to be able to enter a
human being or a fish or whatever it might be. Some chemicals may be out there but not available;
we can measure them, but they’re not really a risk to the ecosystem per se. But processes can
change, which make them available.”

Martin Berg is a professor of Aquatic Ecology at Loyola University Chicago. He says the non-
native species have had a similar impact on PCB transfer from Lake Michigan sediment.

“You can think of it almost like a conduit, like a pipe. Now we have a direct link, as you move up
the food web, to organisms that are going to be directly consumed by humans.”

And the problem spreads as the non-native species expand their range. Researcher Gene Kim says
that the implications are far-reaching.

“Not only are we just talking about a Great Lakes phenomenon – zebra mussels have already
escaped into the Mississippi drainage, and right now round gobies – we’re spending a lot of money
to prevent round gobies from entering that same drainage.”

Scientists’ concerns about toxins in the Lakes are not limited to how invasive species are changing
the food web. Researchers say that other changes caused by people can help harmful chemicals
trapped in sediments to return to the ecosystem. Ultimately, they say, each of these issues is part
of a much larger concern: the overall health of the environment.

For the Great Lakes Radio Consortium, I’m Carolyn Gramling.

Related Links

Coast Guard Preparing Ballast Standard

The U.S. Coast Guard is working to develop a new standard for cargo ships to help stop the spread of aquatic invasive species. Officials are holding five public meetings to discuss the environmental impact of such a standard. The Great Lakes Radio Consortium’s Mark Brush reports:

Transcript

The U.S. Coast Guard is working to develop a new standard for cargo ships to
help stop the spread of aquatic invasive species. Officials are holding five
public meetings to discuss the environmental impact of such a standard. The
Great Lakes Radio Consortium’s Mark Brush reports:


At the moment, foreign ships coming into the Great Lakes are supposed to exchange
their ballast water in the open ocean to flush out foreign organisms, such as
zebra mussels. But no one knows how effective that is. Now, the Coast Guard
is developing a standard that will establish how biologically clean a ship’s
ballast water has to be.


Mike Gardiner is a commander with the U.S. Coast Guard in Cleveland:


“I think that some of the preliminary work would indicate that if you eliminate
organisms above a certain cutoff, and you take care of everything that size and
above then you tremendously reduce the chance that you’re going to have an
invasion.”


The Coast Guard is holding a series of public meetings across the country in the
next month in including one in the Great Lakes region. They hope to get input
from biologists, the shipping industry, and environmentalists to help develop
the national standard.


For the Great Lakes Radio Consortium, I’m Mark Brush.

Related Links