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Round Goby Containment (fwd)
- Subject: Round Goby Containment (fwd)
- From: Carol Ratza <cratza@glc.org>
- Date: Mon, 28 Jul 1997 12:44:51 -0400 (EDT)
- List-Name: GLIN-Announce
---------- Forwarded message ----------
Date: Mon, 28 Jul 97 12:04:34 -0700
From: rich_greenwood@mail.fws.gov
Subject: Round Goby Containment
TITLE: Scientists seeking to contain foreign fish in Midwest
waters
CREDIT: Associated Press
EST. PAGES: 1
DATE: 07/24/97
DOCID: MSP824269
SOURCE: Star-Tribune Newspaper of the Twin Cities Mpls.-St.
Paul; MSTN
EDITION: METRO; SECTION: NEWS; PAGE: 04B
ORIGIN: Chicago, Ill.
(Copyright 1997)
Scientists are planning a shocking surprise for the round goby, a
destructive little fish that seems determined to follow the zebra
mussel into Midwestern waterways.
In an attempt to contain the goby in the Great Lakes, the U.S.
Army Corps of Engineers is planning to set up an underwater electric
barrier in the Chicago Sanitary and Ship Canal - the only link
between the Great Lakes and the Mississippi River.
If the goby makes it to the Mississippi, it could invade the
entire river drainage basin and threaten native species.
"They are in the same gateway that the zebra mussel used to get
to the Mississippi River, and the zebra mussel is now found from
Minnesota to New Orleans and as far west as Oklahoma," said Pam
Thiel, of the U.S. Fish and Wildlife Service.
The 5- to 6-inch, pug-nosed European fish made its way into the
country about seven years ago in the ballast tanks of oceangoing
vessels, much like the zebra mussel before it.
Some scientists thought the goby arrival would solve the
problem of the zebra mussels because the fish eats the mussels. But
the two species are thriving together, and the aggressive goby has
turned on native species in the Great Lakes.
Thus the last-ditch effort by scientists to create an underwater
electric barrier. They've been employed for decades to pen in fish,
but not to fend off an invasion.
The corps plans to install a grid of wires and electrodes about
165 feet wide and 23 feet deep on the canal bottom. When power is
pumped into the grid, the water above it would come alive with
current. The jolts are not lethal to fish and people, according to a
manufacturer of the device. Scientists will conduct laboratory tests
in coming weeks to see how gobies respond to electric fields.
"If this thing tickles them, it might speed them up and make
them swim faster through it," said John Gannon, a science adviser
with a U.S. Geological Survey science center in Ann Arbor, Mich. It
might also paralyze the gobies, and the canal's flow would then
carry the fish on a miserable but short journey through the electric
field.
The hoped-for result is that many fish would swim above the
grid, but the goby and other bottom-dwellers would be turned back by
it.Construction on the project could begin next year.
DESCRIPTORS: animal; maritime; natural resource