Tag: fisheries

Asian Carp Found in Lake Calumet

  • The Bighead Asian Carp found in Lake Calumet. The first physical specimen found beyond the USACOE's electric barrier. (Photo courtesy of the Asian Carp Regional Coordinating Committee)

A Bighead Asian Carp has been found in Lake Calumet in Illinois. This is the first carp to be found beyond the U.S. Army Corps of Engineer’s electric barrier system. Shawn Allee has been covering this story for us and Rebecca Williams caught up with him:

MORE FROM THE ASIAN CARP COORDINATING COMMITTEE

MORE ON THE ASIAN CARP FROM TER

Transcript

The elusive Asian carp, not so elusive now.


This is The Environment Report. I’m Rebecca Williams.


Two species of Asian carp have been moving east, closer and closer to the Great Lakes. There’s a system of electric barriers in a canal near Chicago that are supposed to be the last line of defense. But scientists have wondered whether these carp already swam past that barrier and are breeding in or very close to Lake Michigan. They got that hunch because last year they detected Asian carp DNA in rivers and streams connected to the lake. Now, their fears are confirmed. They found an Asian carp past Chicago’s electric barrier. Shawn Allee reports for us in Chicago and Shawn is here to bring us up to speed.


So where did they find this carp?


Shawn: They found a single 20-pound male Asian carp in Lake Calumet, that’s just west of Lake Michigan.


Why is this location important?


Shawn: Well, I talked to a scientist about that. His name is John Rogner and he’s with the Illinois Department of Natural Resources. He tells me that Lake Calumet is open and it connects to a small river that is also connected to Lake Michigan. And there’s more on this too:


“When you look at Lake Calumet it does appear to us to be ideal habitat. These fish prefer quiet waters in large river systems. You’ll find them in the backwaters and side channels and so Lake Calumet really fits that model to a tee.”


Shawn: But, here’s the thing Rebecca. Commercial fishermen found this Asian carp in Lake Calumet and federal scientists and contractors had already looked there for Asian carp so now they have to go back again.


So why does it matter if the carp is there?


Shawn: Well, these two species of Asian carp are voracious if they’re in the right kind of environment. Basically, they can overtake a food system. They breed so much and they eat so much that there is not enough food for other species of fish to eat. That sort of thing has already happened in the Illinois River system. That’s a river that goes between the Mississippi River in the west all the way to Lake Michigan in the east. And John Rogner tells me that they’re still trying to figure out if this Asian carp is the only one in Lake Calumet or if it’s got a lot of company in there. So they’re going to be using nets and poisons to find that out.


“What we’re trying to determine now is does this fish might represent an individual fish in the lake or might it be part of a larger population and that’s what our intensified sampling over the coming days and maybe even weeks is intended to tell us.”


Shawn: Rogner tells me that they’re going to be testing this particular fish’s DNA down in Springfield, Illinois to see if the fish grew up in the wild or if someone may have moved that fish from somewhere else and maybe just dropped it into Lake Calumet.


Okay, so what are they going to be doing next?


Shawn: They’re going to be going back over places that they have already looked because it’s obvious that they’ve missed at least one fish and they think that maybe they’ve missed some more. The other thing they’re going to be doing is studying whether this kind of carp could breathe in the lake, as Rogner mentioned before. But, one thing they will not be doing is this. They’re not going to be closing the locks that connect Lake Calumet and the rivers in that area to Lake Michigan.


Why not?


Shawn: Well we got one answer from the Army Corps of Engineers. That’s the federal agency that runs the locks. Here’s Mike White:


“At this time we see no reason relative to the threat that’s been identified to take any step for permanent lock closure.”


Shawn: White says the real reason that they’re not really all that worried at this point is that there is just one live fish that they’ve found and it would be expensive to stop barge and boat traffic just for that.


But nobody knows for sure whether there are any Asian carp past the barrier.


Shawn: Not at this point.


Alright, thank you Shawn.


You’re welcome, Rebecca.


That’s The Environment Report. I’m Rebecca Williams.

Oil Spill Worse by the Day

  • The gulf region is the world's largest producer of oysters and shrimp(Photo courtesy of the NOAA)

When an oil rig off the coast of Louisiana exploded last week, gulf coast officials knew they had a problem on their hands. But as Tanya Ott reports from Alabama, everyday they find it’s worse than they originally thought.

Transcript

When an oil rig off the coast of Louisiana exploded last week, gulf coast officials knew they had a problem on their hands. But as Tanya Ott reports from Alabama, everyday they find it’s worse than they originally thought.

It’s estimated more than 200-thousand gallons of oil are spewing out of the well each day. Cleaning up using chemicals causes problems because it might make it easier for marine animals to eat the oil. Burning the oil on the water is not great either. Casi Callaway is with the environmental group Mobile Baykeeper.

“The air quality impacts from it and therefore the health impacts from it are great – and frankly unknown.”

It’s not just an environmental crisis. It’s an economic crisis. This area is the world’s largest producer of oysters and shrimp. And the pristine gulf coast beaches fuel a tourism industry worth 20-billion dollars a year.

For the Environment Report, I’m Tanya Ott.

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Lake Huron’s Invasive Species

  • Filmmaker John Schmit says he wanted to make this film to show how even the smallest invader could mess up the delicate balance of life in the lake. (Photo courtesy of the NOAA GLERL)

You might call Lake Huron the forgotten Great Lake. There are no major cities on its shores. It doesn’t get the media attention the other four Great Lakes do. But its problems are just as bad or worse. Rebecca Williams reports a new documentary tells the story of Lake Huron’s struggle with dozens of alien invaders… and the biologists and fishermen who are trying to reclaim their lake:

Transcript

You might call Lake Huron the forgotten Great Lake. There are no major cities on its shores. It doesn’t get the media attention the other four Great Lakes do. But its problems are just as bad or worse. Rebecca Williams reports a new documentary tells the story of Lake Huron’s struggle with dozens of alien invaders… and the biologists and fishermen who are trying to reclaim their lake:

The documentary Lake Invaders is a cautionary tale about opening the door to strangers. It tells how Lake Huron was opened up to alien invasive species. The film paints fish biologists as the heroes rushing in.

“Seems like it always has to wait until it’s at a disaster level before you know, we can start fixing it… we’re constantly putting out these biological fires, running from fire to fire, to try to keep them under control. We have to find another way to approach this.”

More than 180 non-native species have gotten into the Lakes… and some of them have turned everything upside down. Long, slithering, blood-sucking parasites called sea lamprey were the first to get in. They slipped through a canal that connects the Atlantic Ocean and the Great Lakes. Lamprey killed off most of the big predator fish in the Lakes.

Then… came the alewife. Since the lamprey had taken out the top predators… there was nothing to eat the invading alewives. In the film… biologist Jeff Schaeffer explains how the small fish took over the lakes.

“At that time over 90% of the fish biomass of Lake Michigan and Lake Huron was probably dominated by the exotic alewife. One of my colleagues refers to the Great Lakes at that time as alewife soup.”

Suddenly… there was a major stinking mess. Each spring, hundreds of millions of dead alewives washed up on shore and rotted. Not the best thing for tourism.

Filmmaker John Schmit says he was surprised to learn what happened to the lakes next.

“The funny thing about the Great Lakes is there’s Pacific salmon in them.”

Schmit says biologists brought in millions of salmon from the Northwest to control the alewives. The crazy thing is… it worked. In the film we see how a 4 billion dollar sport fishing industry was born. And the native fish of Lake Huron were pretty much forgotten about.

The salmon fishery boomed for decades. Until the alewives crashed in 2003.

Fisher Doug Niergarth says then… the salmon started starving.

“Two years ago we saw some monster salmon heads that were sitting on little dwarfed bodies. And it was the ugliest thing and rather nasty. Just skinny and withered away. It was the nastiest thing you ever done seen.”

The fishing industry started slipping away. Marinas just scraped by. Tackle shops and motels closed. People finally realized there was something wrong with the lakes.

John Schmit says he wanted to make this film to show how even the smallest invader could mess up everything… both the delicate balance of life in the lake and the people who fish it and depend on money from tourism.

“Lake Huron has been the most impacted by the newest invaders. My personal concern, my investment in the Great Lakes and making this documentary is for people to be aware of the kind of damage invasive species can do to these huge lake systems.”

He says his film Lake Invaders is an example of what invasive creatures can do… not just to Lake Huron… but any ecosystem.

For The Environment Report, I’m Rebecca Williams.

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The End of the Line

  • The documentary, The End Of The Line, takes a look at the status of the world's oceans (Photo courtesy of End Of The Line)

Fish is a big part of our diet. We eat everything from fish sticks and fast food fish sandwiches to sushi and swordfish steaks. But Lester Graham reports a new documentary makes the case we’re overfishing the oceans:

Transcript

Fish is a big part of our diet. We eat everything from fish sticks and fast food fish sandwiches to sushi and swordfish steaks. But Lester Graham reports a new documentary makes the case we’re overfishing the oceans:

This new film is called The End of the Line.

“Everybody recognizes that there’s major problems with the world’s fisheries. And at one level it’s a question of ‘how bad is it?’”

That’s Ray Hilborn of the University of Washington, one of the scientists in the documentary.

The film is a compelling argument that huge fishing trawlers are pushing the fish stocks to the edge.

The first sign of a problem was the cod fishery off the coast of Newfoundland. It collapsed in the 1970s.

But it seemed, despite problems around the world, the total catch around the globe was going up every year. That is, until researchers realized just a few years ago, Communist officials in China were reporting inflated fish numbers to impress their superiors. The world catch was actually getting smaller.

Scientists were stunned, and worried.

“For the first time in human history, the future of the food the world gets from the sea was in doubt.”

“Send a shiver down my spine because that was the one thing a lot of people were holding on to: well, things may be bad, but at least we’re catching lots and we’re catching more every year, so, it can’t be that bad.”

Boris Worm at Dalhousie University is one of the researchers who confirmed the world catch is getting smaller.

He and others have been studying the fact that boats are catching fewer fish, even though the nets are larger and the long lines put out more hooks.

Claire Lewis produced The End of the Line documentary. She admits, this leaves people who see fish as a good source of low-fat protein in a spot.

“It’s very hard. As a parent, you have conflicting evidence. You want to give your children and you want to feed yourself healthy food. You know that’s what fish is. On the other hand, you cannot possible ignore what we’re doing to the oceans, to the ecosystem in the ocean in eating too many fish.”

“Today in every ocean of the world, high-tech industrial vessels are hunting down every known edible species of fish.”

Ray Hilborn: “The basic problem in most fisheries that are in troube is too many boats.”

Charles Clover: “Too much capacity chasing too few fish.”

That last speaker is Charles Clover. The film documentary is based on a book he wrote by the same title. Like the film’s producers, he wants people to be more aware of the plight of the world’s fisheries.

Producer Claire Lewis says there are examples where fishing is being controlled more carefully.

“The most graphic example, I think, in our film, is that fact that in Alaska – which is a very well managed fishery – they take 10% of the stock only. In the North Sea in the E.U., they take 50% of the stock. Now, it seems to me that’s a really, really big difference.”

Lewis says, if left to the big commercial fishing operations, they’ll just keep fishing until fish stocks collapse. And she believes stricter government regulations and better informed consumers are the only things that will stop them.

“I really do believe that it’s the individual consumers who are going to make a difference to this. I think it’s something we can all individually do.”

The film tries to get people to start thinking about what they can do: such as, asking about the fish before you buy it, letting politicians know a sustainable fishery is important, and it encourages people to get involved with groups such as Seafoodwatch.org.

The End of the Line is narrated by actor and environmental activist Ted Danson. It’s appearing in theaters across the nation.

For The Environment Report, I’m Lester Graham.

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White House Weakening Endangered Species Act?

  • Environmentalists warn the Endangered Species Act is in danger during the last months of the Bush Administration (Photo courtesy of the US Fish and Wildlife Service)

The Bush administration is making a proposal that environmentalists

say will weaken the Endangered Species Act. The proposal would eliminate a

requirement for independent review of big federal projects such as highways,

bridges or dams. Lester Graham reports:

Transcript

The Bush administration is making a proposal that environmentalists

say will weaken the Endangered Species Act. The proposal would eliminate a

requirement for independent review of big federal projects such as highways,

bridges or dams. Lester Graham reports:

Right now the U.S. Fish and Wildlife Service or the National Marine Fisheries Service
reviews anything like that that could harm endangered species.

The Secretary of the Interior says the existing regulations create unnecessary conflicts
between agencies and delays on important projects.

The new proposal would let the agency in charge of construction decide for itself if the
project would affect an endangered species.

Bob Irvin is with the environmental group, the Defenders of Wildlife. He says this
proposal eliminates safeguards.

“Previously the Fish and Wildlife Service had a role in reviewing the impacts of those
actions. So, literally, what the administration is proposing is to put the fox in charge of
the chicken coop.”

That’s not the way the Department of Interior sees it.

Kaush Arha is a Deputy Assistant Secretary for the Department of Interior. He took
issue with the fox in charge of the chicken coop metaphor.

“I think that’s an exaggerated statement. And it is unfounded hyperbole. What you are
referring to as “fox” in that particular issue are very, very well qualified, very well
respected and dedicated natural resource management agencies like the U.S. Forest
Service, like Bureau of Land Management, Army Corps of Engineers and others.”

But, no matter how dedicated those wildlife officials are, the Bush administration has a
reputation of putting political pressure on scientists in several agencies, and science
has been changed or rigged in favor of industry.

But the Interior Department says the agencies operate within a political environment.

Deputy Assistant Secretary Arha says, besides, the agencies already make decisions
about federal projects and the Endangered Species Act this way. The proposed
changes would just make current practices clearer for the agencies without completely
overhauling the procedures.

“This captures the existing practices, clarifies and gives more direction and it is narrowly
tailored to do so.”

Environmentalists such as Bob Irvin see something much more sinister than the
administration making things clearer for the different agencies affected by the
Endangered Species Act.

“With barely five months left in the administration, they’re trying to ram through a
proposal to weaken the Endangered Species Act. This is completely in keeping with the
anti-environmental record of this administration. But it is also completely outrageous.”

Environmental groups likely will end up taking the issue to court. The Bush
Environmental Protection Agency tried a similar attempt to by-pass independent
review. The federal courts struck that effort down.

For The Environment Report, this is Lester Graham.

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Killing the Common Carp

  • The Common Carp was introduced a century ago and has been causing havoc in rivers, ponds and lakes ever since. (Image by Duane Raver, courtesy of the U.S. Fish and Wildlife Service)

In thousands of lakes and ponds across the country, there’s a fish messing up the water.
Some biologists say we’ve never seen these lakes the way nature intended due to the
common carp. The usual method to get rid of the common carp is to kill everything in
the lake and start over. Some biologists think there’s got to be a better way. Joel
Grostephan reports:

Transcript

In thousands of lakes and ponds across the country, there’s a fish messing up the water.
Some biologists say we’ve never seen these lakes the way nature intended due to the common carp. The usual method to get rid of the common carp is to kill everything in
the lake and start over. Some biologists think there’s got to be a better way. Joel
Grostephan reports:


Common carp are like underwater pigs. They root up aquatic plants. They constantly stir
up the mud in the bottoms of lakes, making them murky. And in some lakes, common
carp make up more than half of the total weight of fish. Peter Sorensen is a fisheries
professor at the University of Minnesota:


“With their habit of rooting around night and day, they will completely destroy the
bottoms of lakes, so they become cesspools.”


And it ruins the habitat for many birds and fish too:


“The fact is they are doing enormous damage. At a level that I don’t think people
fully realize. They are living with us, and we don’t know in many cases, what
these lakes and streams and rivers should be like and could be like.”


Common carp have been in U.S. lakes and ponds for more than a century. They came
from Europe and Asia. At the request of new immigrants, the United States government
stocked carp in lakes and rivers in the late 1800’s. Sorensen says it didn’t take long before
there were problems.


By the early 1900’s, it clicked this was a huge mistake, and they started to remove
them. Good records were not kept, and Sorensen says the overall impression is that
removal efforts didn’t work. Most attempts to control the fish are still unreliable. The fish
is very tough. It spawns every year, and females produce nearly a million eggs.


Fisheries managers try to control carp the best they know how. Some hire commercial
fisherman to net the carp. They also use poison — killing all the carp and all the other
fish in the lake and then start over.


Fisheries managers currently use a chemical called Rotenone, which they say is not toxic
to humans. Lee Sundmark is with the Minnesota Department of Natural Resources:


“If we see that a lake that a lake way out of balance, might have a lot of carp,
bullheads, tried biological means, and they aren’t working. Sometimes we get to the
point where we use Rotenone to treat it. We basically clean a lake out, and then we
might restock it.”


The trouble is sometimes not all the carp die. And just a handful of them can reproduce
and dominate that lake within a few years. Peter Sorensen and his team of researchers
believe there’s a better way. Sorenson says he does not object to Rotenone poisoning out-
of-hand but, he says, it’s expensive, heavy handed. He and his team have been studying
carp-infested lakes for the past three years to see if they can come up with a new method
to control the fish.


On this cold day, the biologists are surgically implanting radio tags in carp. The
scientists will be tracking these fish so they can find weak points in their lifecycle.
Prezmyslaw Bajer and his colleague Mario Traveline are about to operate on a fish they
caught:


“She will be collecting data that we will then use to remove carp from the lake. She
will be our carp spy.”


The researchers say if they can figure out the habits, and the instincts of the Common
Carp, they will able to control them in way that’s both — effective, and doesn’t kill all the
other fish in the lake. The study’s lead investigator, Sorensen, says this is important
work:


“Something must be done. This is our first, and most damaging species, and if we
don’t do something with this, that like I said, we can do something about — I wonder
what hope there is for any of them. This is to me, the one you got to take out.”


Sorensen says he hopes he can create a model that can be replicated in different parts of
the country. If he’s successful, the ponds, lakes and rivers that have been assaulted by the
carp for the last century might once again be able to host fish and other wildlife that were
forced out.


For the Environment Report, I’m Joel Grostephan.

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Part 1: Tidal Power in the Pacific

  • Research teams are looking for turbines that make tidal power work without harming sea life, like this one. (Photo courtesy of Charles Cooper with Oceana Energy)

For decades, people in the Pacific Northwest have relied on hydropower
for most of their electricity. But dams hurt salmon runs and river
ecosystems. That’s sent Washington utilities on a quest for new, cleaner
sources of power. As Ann Dornfeld reports, some are looking for new ways
to harness the power of flowing water:

Transcript

For decades, people in the Pacific Northwest have relied on hydropower
for most of their electricity. But dams hurt salmon runs and river
ecosystems. That’s sent Washington utilities on a quest for new, cleaner
sources of power. As Ann Dornfeld reports, some are looking for new ways
to harness the power of flowing water:


It’s a brilliant day outside. Craig Collar is perched on a rocky outcropping
overlooking rushing green water swirling and eddying below. Collar says
the water is moving so quickly because this is one of only two spots where
the Pacific Ocean flows into Puget Sound:


“As the tide comes in, it comes into this constrained passageway at
Deception Pass. Y’know, all that energy gets channeled, focused
through this very narrow area. So that’s what results in these rapid
tidal currents that we’re seeing right here.”


Collar researches new power sources for Snohomish County Public Utility
District. His goal is to use a sort of underwater windmill to convert some of
this water’s energy to electricity and funnel it onto the power grid. It’s called
“tidal power.”


Collar says there are dozens of underwater turbine designs to choose
from. Some look like a standard wind turbine with three big blades; others
look like a metal donut or a fish tail.


The Utility District is considering putting underwater turbine farms at half a
dozen locations around Puget Sound. It estimates tidal energy could power
at least 60,000 homes. Collar says the technology has a lot going for
it. It doesn’t emit carbon dioxide or other pollutants. He says underwater
turbines can be much smaller than wind turbines because they’re so
efficient:


“And that’s just as a result of the higher density of water. Water’s
roughly 800 times denser than air, so it contains a lot more energy.”


Unlike the wind, tides aren’t really affected by the season. You know the
saying: “predictable as the tides.” Collar says lunar phases let you forecast
the tides for decades into the future:


“Where with wind, you’re doing good if you can forecast hours or
even a little bit ahead. That really helps utilities like us integrate that
power into the power grid.”


Collar acknowledges there are a lot of questions about the impact of tidal
turbines on marine ecology.


These questions worry nearby Native American tribes. The Tulalip
reservation is close to Deception Pass, and they fish throughout Puget
Sound. Darryl Williams is the tribes’ environmental liaison:


“Five species of salmon, orca, grey whales, eagles, hawks, falcons…
y’know, we have numerous species of fish and marine mammals and
migratory birds that use the areas that are being proposed for these
turbines, and the studies really haven’t been done yet to show what
the impacts may or may not be.”


Along with the marine environment, Williams says the tribes are worried
that tidal turbines could scare away fish or get tangled in fishing nets.


“For the tribes, the fisheries aren’t only an economic source but
they’re also part of the tribes’ culture. Most of our cultural activities
are centered around salmon, and if we can’t catch the salmon, then
that part of our culture really goes away.”


A research team at the University of Washington is looking for ways to
make tidal power work without harming sea life. Brian Polagye is a
mechanical engineering graduate student whose focus is renewable
energy. His team is working with the oceanography department to look at
the ecological risks of tidal power. But Polagye says there are a lot of
misconceptions about what those risks are.


“The most obvious one is the question of ‘Oh! So you’re going to put
these rotors in the water and you’re gonna make sushi in addition to
electrical power.’ People view these turbines kind of as almost a
propeller that’s moving through the water so rapidly that if anything
gets near it it’s gonna get chopped to pieces. In practice, you can’t
actually run the rotors that fast. The maximum speed that the tip of
the rotor can turn at is about 25 miles an hour. Which is actually
relatively slow.”


Polagye says one of the biggest risks is that removing some of the energy
from the tidal currents will change the ecology downstream. He’s studying
how much power can be extracted from an estuary before it has a
noticeable effect on the ecosystem.


Back at Deception Pass, Craig Collar with the utility district says even if
there is a small ecological impact, it’s key to look at the overall picture:


“At the end of the day the thing that’s compelling about tidal energy
for us is there just aren’t very many opportunities for clean,
renewable, emission-free energy that’s both predictable and close to
the loads. And all those things are true for tidal energy in the Puget
Sound region, and there simply is no other renewable for which all
those things are true.”


The utility is working with the University of Washington to figure out
whether tidal power is viable in Puget Sound. If so, it could help reinvent
hydropower on the Pacific Coast for the next generation.


For the Environment Report, I’m Ann Dornfeld.

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Power Plants Kill Trillion Fish a Year

  • Power plants take in a lot of cooling water. Fish and other aquatic life are sucked into intake pipes and die. (Photo by Lester Graham)

Hundreds of electric power plants might have to find alternate
methods of cooling in the future. As Tracy Samilton reports, a federal
appeals court judge says the plants are killing too many fish:

Transcript

Hundreds of electric power plants might have to find alternate
methods of cooling in the future. As Tracy Samilton reports, a federal
appeals court judge says the plants are killing too many fish:


For electric power plants located near water, it’s cheap and efficient
to run lots of water through the plants for cooling. But untold
numbers of fish and other aquatic life are killed in the process.
Eddie Scher is a spokesman for the environmental group Waterkeeper
Alliance. He says overall, the industry might kill a trillion fish or
more each year.


“It’s funny that we sit around and talk about other
problems with our fisheries – there are other problems with our
fisheries – but – this is big one!”


A federal appeals court recently ordered the U.S. Environmental
Protection Agency to change its rules regarding cooling systems, and to
place fish first and costs to the industry second. The electric power
industry says new cooling systems could cost millions per plant, and
instead, they should be allowed to restock fish to replace the ones
they’ve killed.


For the Environment Report, I’m Tracy Samilton.

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Invasive Die-Off Stirs Fishery Debate

  • A naturally reproduced wild lake trout fingerling. (Photo courtesy of MI DNR.)

The fisheries in the Great Lakes are seeing dramatic changes. In one lake, an invasive species that has become part of the food chain has collapsed. But some native fish are doing better because of that collapse. Lester Graham reports some fishery managers are debating what to do next:

Transcript

The fisheries in the Great Lakes are seeing dramatic changes. In one lake, an invasive species that has become part of the food chain has collapsed. But, some native fish are doing better because of that collapse. Lester Graham reports some fishery managers are debating what to do next:


When we started digging canals, connecting the lakes to the Atlantic Ocean, things changed a lot for the fish in the Great Lakes.


First, the sea lamprey got into the lakes through the Welland canal that bypasses Niagara Falls.


The lamprey is an eel-like parasite that nearly wiped out the big fish in the Great Lakes by attaching to them and sucking the life out of them.

Also slipping through the canals was a smaller fish, the alewife. Since the lamprey wiped out most of the predator fish in the lakes, the alewife population exploded. They out-competed native fish for food. It got so bad, that by the mid 1960s, if you weighed all the fish in Lake Michigan, more than 80% of the weight would have been alewives.


So, once wildlife managers got the sea lamprey under control, they had to figure out what they could do to get alewives under control. The fish biologists decided to introduce new predators, trout and salmon, to prey on the alewives. These fish were not native to the Great Lakes. Expensive nurseries were built by federal and state game agencies to keep supplying new trout and salmon every year to prey on alewives.


Forty years later, in Lake Huron, the alewife population collapsed, and in Lake Michigan alewives are declining rapidly. Mission accomplished, right?


Well, in that 40 years, a whole recreational fishing industry has grown up around fishing for those introduced trout and salmon. Some fishery managers now say we have to find a balance of the right amount of alewives to sustain the introduced trout and salmon fishery. So, recently states have cut their trout and salmon stocking programs to give alewives a chance to recover.


Tom Trudeau [who] operates a fish nursery for the state of Illinois says it would cause trouble to try to take the Great Lakes back to native fish only.


“We do have this industry that we have pressure to keep. You know, you’re putting a lot of people out of business if you get rid of it.”


And Trudeau says because of ecological damage, many of the smaller native fish on which big predators used to feed have been wiped out.


“So, I mean, of the six or seven species in that category, we only have one. And a couple of them are extinct. So, I mean, we could talk about going back to the ideal situation of pure native species, but we’ve disrupted the habitat so much.”


So, the argument goes, the invasive alewives are now needed. But something unexpected happened when the alewives disappeared from Lake Huron. The native fish, walleye, yellow perch, and lake trout started doing better.


Dave Fielder is a fisheries research biologist with the Michigan Department of Natural Resources.


“We’ve long known that adult alewives were a predator and a competitor on newly hatched perch and walleye fry. We just didn’t realize how substantial that effect was until finally the adult alewives were removed from the system and now we’re enjoying some greatly increased reproductive success. Walleye, particularly in Saginaw bay, are at some of the highest levels that we’ve seen in a long time.”


But, after 40 years, people are used to fishing for those introduced trout and salmon. And some fisheries managers are wondering what will happen to all those expensive nurseries that provide their jobs.


What happens to all of those charter boat fishing operations, fishing tourism, if the government were to stop stocking those trout and salmon? Would they switch to fishing for native fish? And, can the native fish even survive in the long-run since so many of the smaller native prey-fish are no longer around?


Dave Fielder says it’s hard to say.


“So, we’re kind of in the middle of a change – it’s really a paradigm shift in many ways – and that’s always scary because nobody really knows how we’re going to end up, but I prefer to be optimistic. I think there are a lot of reasons to be hopeful in regards to the benefits that we’re seeing for our native species.”


But some fisheries managers say the debate of whether to go all native or to try to find the right mix of native and non-native fish is not over. Since invasive species, pollution, and habitat destruction have changed the Great Lakes so much, wildlife managers think they’ll still have to keep stocking one kind of fish or another to keep the recreational fishing industry going. If that’s the case, does it matter whether it’s native fish, or the introduced fish that anglers have grown to like so much?


For the Environment Report, this is Lester Graham.

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Invasives Destroying Great Lakes Food Chain

  • Biologists sorting fish. The populations of smaller fish that game fish eat have collapsed in Lake Huron. (Photo courtesy of MI DNR)

Although zebra mussels have been affecting the ecology of the Great Lakes since they were first found in 1988, researchers are continuously surprised at how much damage they’ve caused. Now, biologists are wondering if zebra mussels and the more recently arrived quagga mussels are to blame for a collapse of the fishery in one of North America’s largest lakes. Lester Graham reports the researchers are also wondering if this collapse is a preview of what will happen to all of the Great Lakes:

Transcript

Although zebra mussels have been affecting the ecology of the Great Lakes since they were first found in 1988, researchers are continuously surprised at how much damage they’ve caused. Now, biologists are wondering if zebra mussels and the more recently arrived quagga mussels are to blame for a collapse of the fishery in one of North America’s largest lakes. Lester Graham reports the researchers are also wondering if this collapse is a preview of what will happen to all of the Great Lakes:


It’s off-season for charter boat fishing and Captain Wayne Banicky asked if we could meet at a local watering hole called the Boat Bar. Captain Banicky takes people out fishing on Lake Huron. Well, he used to. The past few years he’s been charter boat fishing in Lake Michigan. He says fish started to become more scarce on Lake Huron, and he was forced to make the move.


“Economics, pure and simple. Dollars and cents. Once you start seeing a decline and being on the water every day and you see those declines in your numbers, it’s just a matter of time before financially you can’t afford to stay there. Those dock fees aren’t given up free. That’s an expensive tab to pay every year.”


Fishing for most species in Lake Huron is not good. But the story is not just a matter of not stocking enough fish or just a bad year, it’s a matter of a collapse of the bottom of the food chain. It’s not just the fish sport fishers like to catch that are down, it’s their prey: the smaller fish those big game fish eat. Prey fish stocks have collapsed, and supplies of the food those small prey fish eat, the plankton, have also collapsed.


Jim Johnson is with the Michigan Department of Natural Resources Alpena Fisheries Research Station.


“There was a huge decline in the amount of nutrients available to zooplankton and phytoplankton in the middle of Lake Huron. These are the basic nutrient bits that fish eat. And it appears now to most of us in the scientific community that a large portion of the nutrients that used enter Lake Huron are now being trapped by zebra and quagga mussels and not finding their way to alewives and other prey fish.”


Scientists from different government agencies and universities in the U.S. and Canada had been noticing changes, but things have gone seriously wrong very quickly in Lake Huron, and it might go wrong other places.


Tom Nalepa is with the National Oceanic and Atmospheric Administration’s Great Lakes Environmental Research Lab. He says tiny aquatic food sources for fish, such as a shrimp-like organism called diporeia, are declining dramatically in other Great Lakes.


“All the players are in place for it to happen in these other lakes too, you know, the loss of diporeia, the expansion of quagga mussels. And maybe Lake Huron is the first to show a collapse in the prey fish. What does it mean? Well basically, you know, there’s not going to be many fish out there for the sport fisherman to catch anymore.”


And sport fishing is multi-billion dollar industry in the Great Lakes. Back at the Boat Bar, charter fishing boat captain Wayne Banicky says fishing is still good in Lake Michigan, but he worries when he thinks about what happened in Lake Huron.


“I think that the fishery as a whole in the Great Lakes is in serious jeopardy right now. Something’s got to be done.”


But the question is what? What can be done when invasive species are changing an entire ecosystem to the point the fishery collapses?


“I don’t know to be honest with you. I don’t think any one of us knows. It’s scary, that much I will admit to you. It is scary right now.”


And guys like Captain Banicky aren’t the only ones worried.


Jim Johnson at Alpena Fisheries Research Station says you can’t undo the damage that’s already done. It’s just a matter of waiting to see how nature responds to the invasive zebra and quagga mussels and other invaders. Johnson says the key is to prevent more invasive species from being introduced to the lakes.


“The best we can do right now, I think the single most effective thing we as managers can do, is to make it understood by the decision makers just how disruptive the invasive species are and try to put a stop to those.”


The source of many of these invasive species is the ballast tanks of foreign ships entering the Great Lakes. Some regulations have reduced the chance that more invasive species will hitchhike to the Great Lakes, but more are still getting in. In the meantime, agencies such as the US Environmental Protection Agency and the US Coast Guard say Congress hasn’t given them the authority to regulate foreign ships strictly enough to stop new invasive species from entering.


So, fishery managers can only watch the other Great Lakes for more signs of a collapse of the fisheries as they’ve only been able to stand by and watch happen in Lake Huron.


For the Environment Report, this is Lester Graham.

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