[Date Prev][Date Next][Date Index]

Round Goby Containment (fwd)

---------- 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 
     CREDIT:      Associated Press
     EST. PAGES:  1   
     DATE:        07/24/97
     DOCID:       MSP824269
     SOURCE:      Star-Tribune  Newspaper of the Twin Cities   Mpls.-St. 
     Paul; MSTN
     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
         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