Invasive Species at the Aquarium

  • Asian carp are one of the invasive species featured in the exhibits in your local museums. (Photo courtesy of USFWS)

Big, public aquariums spend a lot of money to make fish look like they’re at home in the wild. But lately some aquariums are showing fish that are out of place. The GLRC’s Shawn Allee looks at one aquarium’s effort to give them the spotlight, too:

Transcript

Big, public aquariums spend a lot of money to make fish look like
they’re at home in the wild, but lately some aquariums are showing fish
that are out of place. The GLRC’s Shawn Allee looks at one aquarium’s
effort to give them the spotlight, too:


The federal government’s spending millions to keep Asian Carp out of
the Great Lakes. Biologists worry Asian Carp could devastate the lakes’
ecosystem. Recently, though, several carp were brought within sight of
the Great Lakes, and biologists are happy about it.


Chicago’s Shedd Aquarium is on the shore of Lake Michigan. It’s
holding an exhibit of Asian Carp and other alien invasive species.


Curator Kurt Hettinger captured the aquarium’s carp during a trip on an
Illinois river.


“They’re literally jumping, sometimes over the bow of the boat,
sometimes smacking into the side of the boat. I just looked behind me
and was amazed to see all these fish jumping in the wake of the boat, and
to this day, I’m still stunned by this.”


And Hettinger’s more than just stunned. He’s worried.


Asian Carp are an invasive species, basically … pests that crowd out
native fish, and that river where he caught them hooks up to Lake
Michigan.


Again, Asian carp haven’t made it to the Great Lakes, but more than one
hundred and sixty other invasive species have arrived and are breeding
quickly.


One example’s the zebra mussel. At first, scientists worried about how
much money it could cost us. Zebra mussels multiply so fast they can
block pipes that carry cooling water to power plants. But now, we know
the zebra mussel’s disrupting the lakes’ natural food chain.


In other words, invasive species are a huge economic and ecological
nuisance. That’s why the Shedd Aquarium started the exhibit.


“The public I think has seen enough stories about the damages and the
spread and the harmfulness, but those stories are not very often coupled
with solutions.”


That’s ecologist David Lodge. He says the exhibit tries to show how
people spread these species around. Lodge points to one exhibit tank. It
looks like a typical backyard water garden. It’s decked out with a small
fishpond, water lilies, even a little fountain shaped like an angel. It looks
pretty innocent, but Lodge says plants and fish you buy for your own
water garden could be invasive species.


“All those plants and animals that are put outside, then have an
opportunity to spread. Now, it doesn’t happen very often, but with the
number of water gardens, it happens enough so that they are a serious
threat to the spread of species.”


Birds or even a quick flood could move seeds or minnows from your
garden to a nearby lake or river.


The Shedd Aquarium’s not alone in spotlighting invasive species.
Several aquariums and science museums are also getting on board. For example one in
Florida shows how invasive species have infested the Everglades.


Shedd curator George Parsons went far and wide for inspiration.


“I was in Japan last year when we were planning this, and I just
happened to stumble across one of their aquariums and they had an
invasive species exhibit, except that they were talking about large mouth
bass and blue gill. You know, something that is our natives. So, it was
kind of ironic to see that out there. It was kind of neat.”


Like us, the Japanese take invasive species seriously. Back in 1999 the
humble Midwestern Blue Gill created a national uproar. Turns out, they
had taken over ponds throughout the Emperor’s palace, and how did the
bluegill get to Japan?


Probably as a gift from a former Chicago mayor. Apparently, the mayor
thought blue gill might make nice sport fishing in Japan. It was an
innocent mistake, but it’s just the kind of mishap biologists want all of us
to avoid from now on.


For the GLRC, I’m Shawn Allee.

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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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