The Army Corps of Engineers is proposing a plan to stop silver and bighead carp moving from the Mississippi River basin into the Great Lakes.
Cheryl Nenn with Milwaukee Riverkeeper calls the proposal a starting point, not a solution, because multiple aquatic invasive species are threatening both the Great Lakes and the Mississippi River basin.
According to The Nature Conservancy, there are ten species lurking in the Mississippi that threaten the Great Lakes, while 29 species found in the Great Lakes pose risks to the Mississippi.
Nenn says zebra and quagga mussels have already made the move. “(They) have now reached a large section of the continent through this vector. They’ve gotten from the Great Lakes into the Mississippi River system via the Chicago Shipping and Sanitary Canals and have been able to spread through all the tributaries that connect to the Mississippi."
Fish and other aquatic creatures have been free to travel in either direction between the two massive basins since 1900. That's when crews engineered the Chicago ship canal to allow goods and commerce to move between the two basins.
UWM School of Freshwater Sciences researcher John Janssen has evidence that aquatic invaders have made the trip. He points to his research in the 1990s of the round goby, a fish native to the Black and Caspian seas. Janssen says the goby made its way into the Great Lakes through ballast water from seafaring ships. Later it found its way into the Mississippi River system.
“The real issue is as long as that connection is in place, if you get a Lake Michigan invasion that can go down the Mississippi River. Certain invasions in the Mississippi River and the Illinois River connecting it might make it up into the Great Lakes. The issue is really that canal,” Janssen says.
The Army Corps of Engineers plan, that’s still in the public comment phase, aims to hold the carp back just downstream from the Brandon Road Lock in Joliet Illinois.
The proposal includes a barrage of measures to deter the fish, including noise, water jets and an electric barrier.
Whatever strategy the Army Corps chooses, Bob Wakeman takes the approach that everyone is responsible for stopping the spread of invasive species.
He is aquatic invasive species coordinator with the Wisconsin DNR. It reminds people to drain water from their boats and dump unused bait.
“I think it’s every angler that might fish in the Mississippi River, every duck hunter that might duck hunt and might move from one water body to another. I think it’s everybody that enjoys our surface waters have a responsibility to prevent the movement of aquatic invasive species," Wakeman says.
He says for years, the DNR has educated hunters and anglers about the risks of moving aquatic invasive species, and points to surveys that show 90 percent of boaters are aware of the steps they have to take to prevent the movement.
But Wakeman says the DNR is less certain about their compliance.
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