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Great Lakes
Article:
Invasive Species Exhibit Opens at Chicago's
Shedd Aquarium
AP
Published in technewsworld.com on January 9, 2006
"These species are not inherently bad. They're just
in the wrong place," said David Lodge, director of
the Center for Aquatic Conservation at the University
of Notre Dame, who provided advice to the Shedd Aquarium.
The huge Asian carp are real, the gape-mouthed round
gobies are real, but organizers of a new exhibit that
opened this week at the Shedd Aquarium in Chicago decided
not to mess with real zebra mussels -- they're just replicas.
The exhibit concerns threats to the Great Lakes from
invasive species -- plants or animals that arrive in spots
where they didn't originate. They then multiply, spread
and harm the balance of their new environment by eating
or competing with native species.
Wrong Place
An example is zebra mussels, already notorious pests
in the Great Lakes. They are voracious eaters, multiply
quickly and are so stubborn once entrenched that the Shedd
staff worried they could end up clogging the aquarium's
pipes -- hence, the models that climb the side of one
of the exhibit's aquariums.
Scientists believe at least 170 aquatic invasive species
currently live in the Great Lakes basin, according to
the exhibit, and a new species is introduced on average
once every eight months.
"These species are not inherently bad. They're just
in the wrong place," said David Lodge, director of
the Center for Aquatic Conservation at the University
of Notre Dame, who provided advice to the Shedd.
Staff at the Shedd said visitors who have read about
the threat of invasive species often ask to see them.
The exhibit is also designed to provide visitors with
tips about how they can help prevent introducing or spreading
invasive species.
The plants and animals arrive in the Great Lakes region
-- the world's largest surface freshwater system -- in
multiple ways. Some are carried in the ballast water of
cargo ships, others hitchhike rides on fishing gear or
are dumped into sewers and lakes by owners who are tired
of caring for an exotic animal or plant around the house.
"The damages are far-reaching -- from the shoreline,
to the pipes of power plants and municipal waterworks,
to the many other lakes and rivers that are under threat
and indeed under harm as zebra mussels and many other
species spread from the Great Lakes across the continent,"
Lodge said.
Exhibit Highlights
The exhibit is a permanent one, and it takes the place
occupied by several aquariums previously devoted to aquatic
life in the Great Lakes and Midwestern rivers and lakes.
It includes a mix of plants and fish that are native
to the Great Lakes, such as lake sturgeon, the prehistoric-looking
fish with a snout-like mouth and dull brown color.
The noninvasive exhibits include hydrilla, an Asian plant
common used to decorate aquariums, and round gobies, which
eat trout and bass eggs.
One of the exhibit's highlights is an aquarium filled
with Asian carp, which are currently being kept out of
the Great Lakes by electric barriers.
An accompanying videotape shows dozens of carp jumping
four feet in the air out of the Illinois and Mississippi
rivers -- where they've multiplied quickly because of
a lack of natural predators. Some of the carp land in
boats, others hit passengers; in one shot, at least eight
are seen flying in the background.
The carp are "filter feeders" that consume
plankton that would normally be eaten by juvenile minnows,
walleyes and blue gill bass, said Kurt Hettiger, a senior
aquarist at the Shedd.
Hettiger went out on a boat on the Illinois River near
Havana, about 200 miles southwest of Chicago, to collect
the carp for the exhibit. He was dismayed by what he saw.
"It was sort of devastating to see how many of these
fish there were in a small area," he said. "In
some areas, where you sort of start crowding them in,
the water is literally erupting with these fish. It's
sadly amazing."
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