Great Lakes Article:

Zebra Mussels spread to Mississippi above Twin Cities
kare11.com
Posted on October 21, 2005

"I was sent out to clean the minnow bucket and thought, "Oh great! Another chore!"

Despite that, 14-year-old Gil Millette did what he was asked last Sunday and in the process discovered a zebra mussel that had settled on the family minnow bucket which had been floating in Rice Lake all summer.

The Brainerd boy scout showed it to his dad, Hank, who took it to the regional DNR office. They sent biologists out to confirm the spread.

"They found four more on our boat lift and they found about 30 more on our neighbor's dock lift over there," said Gil.

The young man said he recognized the zebra mussel because he'd paid attention when he was shown several on a fishing tip to Wisconsin. He figured his discovery turned what had started as a good day, into a bad one.

Zebra mussels are an invasive species which first turned up in the U.S. 17 years ago in the Great Lakes.

They breed prolifically and as a result they choke out native mussels and cause all sorts of damage to water intake systems on the Great Lakes.

They'd made their way up the Mississippi River to the Twin Cities, and been spread to two Minnesota inland lakes, but until this week, the destructive species had not been found upriver of the Twin Cities.

Five years ago, DNR biologists found them in Lake Zumbro in Olmstead County. Last year, biologists found them in Lake Ossawinnamakee in Crow Wing County. Lake Ossawinnamakee feeds the Mississippi, so it was probable that they would, sooner or later, be found in northern reaches of the Mississippi.

"In Rice Lake, it's very serious because zebra mussels could reproduce in Rice Lake... be moved out into the Mississippi River and be anywhere in the Mississippi River from Brainerd on down to the Twin Cities," said Gary Montz, the DNR's zebra mussel coordinator. That's 160 miles of river.

"The zebra mussel is an external spawner. It kicks the eggs out into the water, and the larval stage, called the velliger, is microscopic and it floats around for two or three weeks until it starts developing a shell, and then it settles to the bottom... During those two or three weeks, it could be swept miles and miles and miles from where the parents are," explained Montz.

Two months ago, zebra mussels were discovered in Lake Mille Lacs, the most popular walleye lake in Minnesota.

Gary Montz says the only way zebra mussels get from lake to lake is on, or in, boats, much the same way Eurasian Milfoil is spread. That destructive aquatic plant is now in control of dozens of lakes across the state.

"You don't know." said Montz, "if you have a live well or a bait bucket that's full of lake water, or full of tens or hundreds or thousands of zebra mussel larvae. Drain that lake water out!"