Invasive Fish Rears Ugly Head in Great Lakes

  • With its ability to breathe out of water and wriggle its way over land during dry spells, the media has dubbed the northern snakehead "Frankenfish." Its appearance in Lake Michigan is scary to scientists. (Photo courtesy of USGS)

A few weeks ago, a Chicago fisherman caused a stir when he found a northern snakehead fish. The discovery set off a frantic search to find out if yet another invasive species is threatening the Great Lakes. The Great Lakes Radio Consortium’s Jenny Lawton has this report:

Transcript

A few weeks ago, a Chicago fisherman caused a stir when he found a northern snakehead fish. The find set off a frantic search to find out if yet another invasive species is threatening the Great Lakes. The Great Lakes Radio Consortium’s Jenny Lawton has this report:


Just before Halloween, the so-called Frankenfish reared its ugly head… filled with sharp teeth… in Chicago’s Burnham Harbor on Lake Michigan. And it’s still a mystery as to just how it got there.


Although the snakehead is arare item in some Asian cuisines, there’s a more common suspicion amongst local experts and hobbyists. That snakehead was probably a pet that outgrew its tank, and instead of the traditional farewell down the toilet, it was set free in Lake Michigan. Free to eat through the Lake’s food web.


Local pet store manager Edwin Cerna says that’s why he stopped selling the fish years before they were banned by U.S. Fish and Wildlife. He remembers one day, when he was adjusting a tank, he accidentally got in between a snakehead’s lunch and its mouth.


“He bit me in the hand… made me bleed. It hurts. It’s got a nice strong jaw and that’s why it’s so dangerous because it can kill big fish, literally cut them in half. It’s almost like a big old killer whale, like a miniature version of it.”


But why on earth would anybody buy a vicious fish that can grow up to three feet long in the first place? Jim Robinett is with the Shedd Aquarium in Chicago. He says he’s a fish geek.


“I gotta say, as a little fish, when you first buy them, they’re really attractive; they’re neat little animals, but they eat like crazy. They’re voracious.”


Robinett knows not to be fooled by the little guys because what happens next is the perfect plot for a B-horror movie. He says the snakehead fish grows quickly, eventually eating everything in its tank. If it doesn’t die from overgrowing that tank, its owner might be tempted to dump it into a nearby body of water where it will keep eating its way up the food chain. Robinett says that’s the fear in Lake Michigan.


“They could potentially start picking off small salmon and lake trout, which is native to these waters here, they’re not real discriminating, they’ve been known to take things as large as frogs, some small birds, even small mammals that happen to get in the way there close to shore. They’ll eat anything they get their mouth on.”


Most hobby fish don’t last long in Chicago’s cold water. But the northern snakehead is different. The snakehead is native to northern Asia, and the Lake Michigan Federation’s Cameron Davis says that makes the fish feel right at home around here.


“It’s a lot like us Midwesterners, it just kind of hunkers down and… that’s part of the problem with the snakehead is that it can live under very extreme conditions. Which means it’ll out compete those other fish, and that’s a tremendous problem.”


Snakeheads have another edge on other species. The fish guard their eggs, giving their young a better chance of reaching maturity. But perhaps the most peculiar thing about snakeheads is that they can breathe. In addition to its gills, they have an organ that works like a lung and allows it to breathe air. It’s able to live up to three days as it uses its fins to wriggle across land in search of another body of water.


But looking down into the murky waters at Burnham Harbor, Davis says we shouldn’t run screaming yet. It’s not exactly a horror film scenario.


“I don’t think that the snakehead is going to come and grab our children out of schools and eat them or anything like that. But it is a problem for those of us who like to fish for yellow perch and whitefish and some of the things that make the Great Lakes so fantatstic, could really be threatened by this fish getting into Lake Michigan.”


Other invasive species cause an estimated 137-billion dollars of losses and damages in U.S. waterways each year. Cameron Davis says simply banning the local sale of fish like snakeheads hasn’t been enough to keep the Great Lakes safe.


“We’ve got to stop imports of these kinds of fish into the United States. We can’t protect the Great Lakes unless we’re checking these things at the door when they come into the country. It’s that simple.”


Davis is pushing for the passage of the National Aquatic Invasive Species Act. The bill would allocate a total of 174-million dollars to develop new technology for identifying and eliminating the invaders if and when they arrive.


So far, local authorities ahven’t found another snakehead near the banks of Lake Michigan, but Cameron Davis says the initial find just proves how hard it is to regulate what comes into the country’s largest body of fresh water.


Standing on the dock at Burnham Harbor, Davis looks out over the dark waters and shakes his head.


“It’s just an indicator that we’re in a race against time right now. Let’s hope that if there are more than one out there, that they haven’t hooked up.”


If they have, he says, it could truly be the stuff horror movies are made of… at least, for the other fish in the Great Lakes.


For the Great Lakes Radio Consortium, I’m Jenny Lawton in Chicago.

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Environmentalists Cheered by Dam Removals

60 dams are scheduled for removal this year across the country. 40 of them are currently located in the eight Great Lakes states. Environmentalists say the removal of these dams will improve water quality and help restore fisheries. The Great Lakes Radio Consortium’s Celeste Headlee reports:

Transcript

60 dams are scheduled for removal this year across the country, 40 of them
are currently located in the eight Great Lakes states. Environmentalists
say the removal of these dams will improve water quality and help restore fisheries.
The Great Lakes Radio Consortium’s Celeste Headlee reports:


A survey by the environmental group American Rivers shows
that more than 145 dams have been removed nationwide since 1999. Serena
McClain is a conservation associate for American Rivers. She says there are
two good reasons why these dams are coming down. First, there’s a growing
concern for the ecological health of rivers and streams. But there is also
an economic benefit to removing some dams.


“It’s an infrastructure that requires constant maintenance and improvement. And a lot of
these dams, too… they’ve outlived their purpose. When they were first built, a lot of them
powered old grist mills, but now they’re just sitting there, kind of rotting away.”


McClain says migratory species like salmon and trout are negatively impacted by dams,
and new evidence shows even fish that don’t travel as far benefit when the structures are
pulled down. About 65 percent of the dams scheduled for removal this year are located
in the eight Great Lakes states.


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

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City Cooks Up New Compost Recipes

  • A pile of food waste awaits processing at a Duluth, Minnesota composting site. A wide variety of materials arrive each day - anything from unused frozen dinners to sheet rock to bird droppings from a nearby zoo. Photo by Stephanie Hemphill.

Lots of people have a compost pile in the backyard. They throw their grass clippings and kitchen scraps in a pile and let it sit. Eventually it turns into rich black stuff that can be spread on the garden. Many cities around the Great Lakes collect residents’ yard waste and turn it into compost on a bigger scale. In Duluth, Minnesota, they’ve taken it a step further. An industrial-sized compost operation uses some surprising ingredients. The Great Lakes Radio Consortium’s Stephanie Hemphill reports:

Transcript

Lots of people have a compost pile in the back yard. They throw their grass clippings and
kitchen scraps in a pile and let it sit. Eventually it turns into rich black stuff that can be spread
on the garden. Many cities around the Great Lakes collect residents’ yard waste and turn it into
compost on a bigger scale. In Duluth Minnesota, they’ve taken it a step further. An industrial-
sized compost operation uses some surprising ingredients. The Great Lakes Radio Consortium’s
Stephanie Hemphill reports:

There’s a steady stream of cars and pickups as people drop off leaves and branches. They’re
piling up their yard waste at the compost site of the Western Lake Superior Sanitary District in
Duluth, Minnesota. The Sanitary District takes care of the trash for Duluth and nearby towns.

At the back, four rows of future compost are cooking in the sun. They’re about 6 feet tall and
half a block long. They were mixed by a master chef of compost, Charlie Hitchcock. He’s about
to cook up a new batch. Today’s mix starts with biodegradable bags of kitchen scraps from
several restaurants.

“It’s a small load today, but it’s food waste and there’s animal hair that’s thrown in from some of
the pet grooming places. A lot of protein and nitrogen in that, I guess.”

Hitchcock consults a laptop computer to create his recipe. He plugs in the weight of the food
waste. The computer program tells him the right proportions of wood chips and leaves to mix in.
It’s aiming for the ideal combination of carbon and nitrogen. Most loads are about half wood
chips.

“Because it aerates it pretty good. And then I just keep punching a number in on the leaves until
I get between a 25-to-1 to a 35-to-1 on a C-N-N ratio, carbon to nitrogen.”

(tractor starts)

The key ingredient that’s loaded in Hitchcock’s mixture is different every day. That’s because the
sanitary district is always trying to divert stuff that would normally go to the landfill. Lately
they’ve been going after some of the garbage itself, not just yard waste. And sometimes that
garbage comes from some exotic places.

(bird sounds from zoo)

Dave Homstad takes care of the birds at the Lake Superior Zoo. He’s giving the parrots some
fresh water.

(parrot chit-chat)

He slides out the bottom of the cage and whisks sawdust and bird droppings into a black plastic
bag.

“The composting stuff goes into a black bag, so that we can keep them separate. And then
anything that can be composted goes in here and then eventually into a dumpster for that
purpose.”

The dumpster gets filled with uneaten food, animal bedding, like straw and sawdust, and animal
dung. At the composting site, the dumpster-load from the zoo might be mixed with scraps from a
coffee shop. A commercial fishing operation brings fish guts. Even sheetrock is ground up to
become compost. The latest addition is waste grain from the elevators on Duluth’s lakefront.

(train sound at elevator)

The Cargill elevator handles 50 million bushels of grain every year.

Roger Juhl manages the operation. He says there’s some spillage when railroad cars have to be
changed from one type of grain to another.

“So we have to clean them out and dump them onto the tracks, and then pick them up and put
them in the dumpster. And that’s where they’ll go to this recycling center.”

Juhl says he’ll probably save some money. He’ll still have to pay the hauler to take the grain
away, but he won’t have to pay for dumping it in the landfill. What’s even better, Juhl says he’ll
be doing something good for the environment.

“Hopefully it’ll be useful for something.”

It’s put to use, all right, in Charlie Hitchcock’s compost mixer.

(compost sound back up)

The mixer’s been turning for 15 or 20 minutes. Hitchcock peers into the barrel. The ingredients
look like chunky dirt, and smell like day-old garbage. He reaches in for a handful.

“I do the squeeze test on it. If you get it packed tight without moisture coming from it, it’s within
the 50% range, which is good.”

Hitchcock is learning how to turn an amazing variety of stuff into compost. Some days he gets a
load of spoiled vegetables from a grocery store. Other times it’ll be outdated frozen dinners.

“When I get a lot of wet pasta, I use some sheetrock and mostly grindings. That’s shredded up
tree branches and limbs that we have. I don’t put leaves in it because the pasta’s so wet, it gets
real gumbo-y.”

After six months in a pile, the compost is ready for customers, like Suzanna Didier.

“I mean, I’m glad they’ve figured out a way for us to decrease the amount of garbage that goes
into the stream, into the waste stream, because obviously that needs to be slowed down a bit. So,
it’s great.”

It’s an expensive operation that doesn’t pay for itself. Officials hope to recoup half their costs by
selling compost. As they get more raw materials, it’ll become more cost effective. Someday,
they hope everyone in Duluth will send their kitchen waste for composting.

For the Great Lakes Radio Consortium, I’m Stephanie Hemphill.

Chefs to Boycott Genetically Modified Fish

People have been eating genetically modified vegetables and grains for several years. Now a genetically altered salmon might be headed for the market. The Great Lakes Radio Consortium’s Rebecca Williams reports that a few hundred seafood retailers are planning to boycott the new fish:

Transcript

People have been eating genetically-modified vegetables and grains for several years. Now, a
genetically-altered salmon might be headed for the market. The Great Lakes Radio Consortium’s
Rebecca Williams reports that a few hundred seafood retailers are planning to boycott the new
fish:


The genetically-altered salmon grow twice as fast as other farm-raised salmon. The Food and
Drug Administration is deciding if it will approve the fish for human consumption.


If it gets to market, it might be tough to find buyers. That’s because of a boycott organized by
environmental groups.


Julie Francis is a restaurant owner in Cincinnati. She’s joining more than 340 chefs, seafood
distributors and grocers in the boycott. Francis is concerned that not enough is known about the
effect on humans and wild salmon.


“I really, being a chef owner, come from the background of, you know, ‘I want the best fish, I
want the best vegetables,’ and I just, it’s just, in my personality, to be concerned about things like
chemicals, and additives, and different things that we just don’t know, I don’t know that much
about.”


The seafood retailers plan to boycott genetically-altered fish until they feel it’s safe to eat. They
also want the FDA to insure that wild fish stocks won’t be harmed.


For the Great Lakes Radio Consortium, I’m Rebecca Williams.

Tracking Long-Term Zebra Mussel Changes

Zebra mussels have been colonizing North American lakes and rivers since 1991. Scientists have looked at many of the ways mussels affect those ecosystems. But a new study underway shows how those effects are moving up the food web…and are having two very different results. The Great Lakes Radio Consortium’s Mark Brodie reports:

Transcript

Zebra mussels have been colonizing North American lakes and rivers since 1991. Scientists have looked at many of the ways mussels affect those ecosystems. But a new study underway shows how those effects are moving up the food web…and are having two very different results. The Great Lakes Radio Consortium’s Mark Brodie reports:


Between 50 and 5-hundred billion zebra mussels now live in New York’s Hudson River. That’s a lot of hungry mouths to feed on the river’s zooplankton and phytoplankton. The problem is the mussels are not the only ones that like to dine on the microscopic plants and animals. A new report suggests the mussels are stealing food from some of the river’s fish.


That’s forcing those fish to look elsewhere for their meals. Sandra Nierzwicki-Bauer is the director of the Darrin Freshwater Institute, and a biology professor at Rensselaer Polytechnic Institute in Troy, New York. She says the zebra mussels can dramatically alter an ecosystem.


“They’re very rapid filter feeders, and as such, they’re able to remove tremendous amounts of phytoplankton, algae, bacteria in the water column. As such, the phytoplankton serves as food sources for other organisms so you really are impacting the entire food web.”


Nierzwicki-Bauer says those impacts go all the way up to fish. David Strayer is a freshwater ecologist at the Institute of Ecosystem Studies, and a lead author of the report on the Hudson River. He says his team studied fish populations in the Hudson both before and since zebra mussels colonized there.


“In open water fish species, we saw a decline in abundance, we saw declines in growth rates, and we saw that the populations of those fish tended to shift downriver compared to the period before the zebra mussel invasion.”


That means some of the most common and popular fish in the Hudson are no longer where they used to be…among them American shad, herring, and white perch. That’s because the zebra mussels are eating those fish’s food…forcing the fish to go elsewhere.


But Strayer says while some fish have had to move away from the mussels…some species have welcomed their new neighbors.


“In the same period of time, we saw populations of fish that live in the weed beds…we saw those populations increase, we saw growth rates of those fish increase, and we saw the populations of those weed bed fish shift upriver into the area where the zebra mussels lived.”


These forage fish have more to eat because the plants at the river’s bottom are growing more. That’s because the zebra mussels clear up the water, which allows more sunlight to reach the plants. Strayer says the zebra mussels have changed almost everything about the Hudson’s ecology.


But he says some of those changes have been difficult to predict, and the changes may not apply to all bodies of water where the mussels have colonized. This is one of the first studies using long term data that looks at the zebra mussels’ affect on fish populations…but there is some evidence that other bodies of water are dealing with similar situations. There have been reports that zebra mussels may be affecting smelt and chub in Lake Michigan…these smaller fish are food for larger species, such as trout and salmon. But while the results are comparable, David Strayer says the changes in the Hudson River are more pronounced than changes elsewhere.


“This isn’t because we have more zebra mussels in the Hudson than in the other places, but it’s because there are differences in the structure of the ecosystem between the Hudson River and the Great Lakes and other places that have been invaded. So, you have to be a little cautious extrapolating from one body of water to the next.”


That sentiment is shared by Andy Kahnly. He’s a fishery scientist with the Hudson River fishery unit of the New York State Department of Environmental Conservation. He also worked on the new study. Kahnly warns for now, the results only apply to young fish…and not adults. That’s because fish can live up to 30 years, and the data don’t go that far back.


“Quite often, changes in early lifestages will take some time to translate into changes in fish populations and then to changes in fish communities. So it takes a lot of data, a lot of years of data to see a change.”


Kahnly says that means anglers in the Hudson might begin to notice some changes over the next few years… and he says the study did find a dramatic decrease in many of the species that people catch.


“If these changes in production of young persist into the future, then definitely there will be a decrease in the abundance of the adults which people are fishing for.”


But that depends on what you’re fishing for. The Institute of Ecosystem Studies’ David Strayer says your perspective might change depending on that you’re trying to catch.


“If you’re concerned about shad populations, if you’re a shad fisherman, then you might be concerned with the zebra mussel invasion and think it’s a bad thing. If you like the weed beds, if you’re a duck hunter or a large mouth bass fisherman this might be regarded as a positive thing.”


Strayer says the study shows zebra mussels are capable of having a tremendous impact on an ecosystem. He says it also shows the importance of being careful to prevent the introduction of invasive species…like zebra mussels…into an ecosystem.


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

COMMENTARY – &Quot;FRANKENFISH" TO HIT STORE SHELVES?

Canadian researchers have developed a genetically altered
salmon. Dubbed "Frankenfish" by the public, the designer salmon grow
about eight times faster – and as much as 37 times larger – than normal
salmon. While fish farmers are hoping to bring their latest catch to
a dinner table near you, Great Lakes Radio Consortium commentator
Suzanne Elston finds the whole thing rather unappetizing:

Success in Controlling the Lamprey

  • Sea lampreys feed on a lake trout. The invasive species damages the Great Lakes fishery. (photo courtesy Great Lakes Fishery Commission)

A new effort to eradicate the sea lamprey is attacking one major
trouble spot. The Great Lakes Radio Consortium’s Lester Graham
reports… the parasite is being trapped and poisoned:

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The Business of Fish Management

  • Similar scenes can be found up and down the eastern shore of Lake Michigan.

Now that summer’s officially here, beaches around the region are packed with
tourists and locals. But this year many beaches have been plagued with
unwanted visitors: tens of thousands of dead fish in the water and on the
sand. It’s a revolting sight-and smell – but in fact, the fish play an
important role in the lakes…and present an ongoing management challenge to
biologists. The Great Lakes Radio Consortium’s Wendy Nelson explains:

Fish Release Scaled Back

There’s a shortage of fish food in the Great Lakes, so Wisconsin and
three other states have agreed to reduce the number of Chinook salmon
released into Lake Michigan in the spring. The action comes because a
limited food supply in the lake could threaten other fish populations.
The Great Lakes Radio Consortium’s Patty Murray reports:

Gender Disparity Endangers Yellow Perch

Scientists in Wisconsin say among yellow perch, males in Lake Michigan outnumber females by 9-to-1. Such a gender disparity may be detrimental to the food chain. The Great Lakes Radio Consortium’s Lisa Labuz has more: