Zebra mussel madness in Alexandria area

Dr. Daniel Molloy described three major impacts caused by the spread of zebra mussels.

By: Wendy Wilson, Alexandria Echo Press

Dr. Daniel Molloy described three major impacts caused by the spread of zebra mussels.

One is recreational. Beach-goers could cut their feet on the sharp mussel shells.

Live mussels also wash onto shore, leaving behind an offensive odor.

The industrial impact of zebra mussels is also significant.

The creatures attach to and clog pipes, causing a myriad of problems and financial burden.

According to Dick Osgood, certified lake manager, irrigation systems for lawn watering are also becoming inundated with mussels.

The third impact of the mussels is ecological.

“[Zebra mussels] feed voraciously by filtering on algae and the next domino to get hit is the microscopic animals that are in that water,” he said. “The dominoes start to fall.”

He explained that insects and fish normally would eat the microorganisms.

“The food chain gets an impact and also the water starts to become clearer because they’re eating those microscopic plants that are making it kind of pea-soupy. Sunlight now can go further down, striking the bottom so that aquatic weeds can start to grow where they weren’t growing,” he said.

The zebra mussels also accumulate polychlorinated biphenyls (PCBs) “which are nasty poisons – you already have that in these lakes,” Osgood said. He also noted, “With zebra mussels… they filter out the algae but they don’t filter out the toxin strains of algae.”

Some of these toxins have been linked to human health impacts, especially in water supply reservoirs.

“They are beginning to find Alzheimer clusters in communities that get their drinking water from reservoirs that have blue-green algae blooms that have formed toxins,” Osgood said.

Zebra mussels talk draws full house

By Casey Merkwan

Concerned community members and experts packed a room at the Chanhassen Community Center last week to learn more about the dreaded zebra mussels.

More than 50 people attended a forum that featured speakers Steve McComas, an aquatic biologist and ecologist, Luke Skinner from the Minnesota Department of Natural Resources and Eric Evenson, district administrator of the Minnehaha Creek Watershed District to talk about the problem of zebra mussels and what’s next for Minnesota lakes.

Skinner said there is no safe way to eradicate zebra mussels, so the focus is on preventing any further spreading.

“There’s a lot of concern about a lot of invasive species but right now the zebra mussel is the poster child for spreading in the state,” Skinner said.

Skinner said it is possible to kill off zebra mussels but there’s risk of killing other species. He also said the larger the lake the harder they are to control.

“In a lake like this [Minnetonka] with this many bays and islands and stuff, the reality of trying to manage it here is it’s not going to happen,” he said.

Since the discovery of zebra mussels in July of last year, experts say the key is to prevent them from spreading.

It’s possible the non-native invasive species have been in Lake Minnetonka for more than two years.

“They were also found on the other side of the dam of Lake Minnetonka so theoretically Minnehaha Creek is considered to be infested as well,” McComas said.

Zebra mussels originated from the Black and Caspian seas in Europe. It is suspected that the species traveled to the United States via cargo ships in the late 1980s.

After the discovery of the zebra mussels in July, agencies performed an enhanced assessment to determine the distribution of the infestation and to find adult zebra mussels to lead them to a breeding point.

“They were fairly hard to find,” McComas said. “In a big lake it really is looking for a needle in a haystack trying to find a breeding population.”

Divers didn’t find a breeding spot. McComas said there was 100 hours of dive time, 30-40 volunteers and 20-30 spots where zebra mussels were found in Lake Minnetonka, mostly on the east side of the lake.

Lake Minnetonka and neighboring lakes were also assessed for how hospitable the lakes were for zebra mussel population growth.

McComas said the calcium levels in all 26 bays of Lake Minnetonka were high enough that they could support optimal growth of zebra mussels.

Other factors that are optimal for zebra mussel growth are PH levels, the right concentration of chlorophyll and bottom conditions.

Zebra mussels attach easily to hard surfaces with substrate, for example rocks. If the bottom of the lake is sand and silt, the mussels can attach to each other as well.

Lake Minnetonka has the conditions that would support moderate growth of zebra mussels and 43 percent of lake bottom could be colonized, McComas said.

Christmas Lake has the potential to have 60 percent of the lake bottom colonized, according to McComas.

Zebra mussels kill native mussels and also compete with young fish for food. They can also block underwater pipes.

McComas said zebra mussels start spawning when the water temperature reaches 54 degrees.

Currently, water temperatures are in the high 30s. By late May the water temperatures will raise to optimal spawning time.

“This isn’t something that the state can do on their own, this isn’t something the watershed district can do on their own, this isn’t something that counties can do on their own. This is going to have a coordinated effort, a cooperative effort to really get anything to happen here and it is going to involve all the agencies, it’s also going to have to involve lake associations and individuals out there,” Evenson said.

As a result Evenson, Skinner and McComas emphasized the need to prevent further infestation of the zebra mussels.

Evenson suggested implementing a red lake, blue lake program to help stop spreading.

The program would use a red sticker to identify when a boat has been in waters infested with zebra mussels. A boat could not enter a lake without zebra mussels until inspected.

The legislature has also gotten involved: a new drain plug law took effect on July 1, 2010. The law states that a person leaving waters of the state must drain boat equipment by removing the drain plugs, bailers, valves or other devices that hold water.

On March 16, Gov. Mark Dayton announced his support for legislation that hopes to minimize the spread of aquatic invasive species.

The bill would require more thorough inspections, double penalties for violations, allow local law enforcement to retain civil penalty amounts for citations issued by their agency, require training for lake providers and require watercraft and operators to have a decal that lists invasive species rules, like a sticker.

The experts encouraged community members to vocalize their concerns with their elected representatives and to also educate their neighbors to slow the infestation of zebra mussels.

Ramp gates a solution for zebra mussels?

Article by: LAURIE BLAKE , Star Tribune

Homeowners on Christmas Lake are pushing for a better way to protect their clean waters.

In another grass-roots attempt to stop the spread of zebra mussels from Lake Minnetonka, homeowners on nearby Christmas Lake are angling to have a code-activated gate installed on the lake’s solitary boat ramp.

“There are huge numbers of lake homeowners who don’t feel the Department of Natural Resources is doing enough,” said Joe Shneider, president of the 140-member Christmas Lake Homeowners Association.

“We can’t just do what we have done in the past, which is monitor and communicate and educate, because it’s just not enough.”

Christmas Lake is one of the cleanest, clearest lakes in the metro area because it is deep, spring-fed and gets no farm runoff.

The lake’s boat ramp on Hwy. 7 in Shorewood is a stone’s throw from Lake Minnetonka, where zebra mussels were discovered last summer. Many boaters take a ride or fish on Lake Minnetonka and then, without having to be inspected for unwanted aquatic plants and animals, go on to Christmas Lake, Shneider said.

Christmas Lake homeowners would like the Minnehaha Creek Watershed District to test the ramp gate idea.

“We would really like to see a strong statewide program put in place to control the spread of invasive species, but if the state doesn’t do that we are willing to step up and do something,” said watershed district administrator Eric Evenson.

The idea is to require boaters to go to one of several locations for an invasive species inspection, where they could get a punch code, similar to an automatic car wash, to raise the gate to the boat ramp, Evenson said.

“If we don’t do something, we are going to lose what people want to get to the lake for in the first place,” Evenson said.

Lake access part of culture

The request comes just weeks after homeowners around Fish Lake in Maple Grove sought to close its only access ramp when it wasn’t staffed for inspections.

The DNR, which would have to approve the gate experiment, has so far refused to limit lake access in the name of controlling invasive species.

“We are concerned about preventing the spread of invasive species but we need to find ways to do it that still allow people to recreate on the lakes,” said Steve Hirsch, director of the division of ecological and water resources.

“Access to lakes is kind of part of the fabric of Minnesota’s culture so I don’t think the DNR can be the sole entity that decides we are going to start trading off access to lakes,” Hirsch said.

The agency is discussing the matter with the state attorney general’s office. Hirsch declined to describe the discussions.

The DNR’s approach to aquatic invasive species has been to station inspectors at busy lakes during peak hours and educate the public about how invasive plants and animals are spread. The agency is recommending that legislators provide more funding for expanded lake inspections and enforcement.

Hirsch acknowledged that even if legislation providing more inspectors passes, lakes would not have complete inspection coverage.

Gate approach worth a shot?

At Fish Lake Regional Park, operated by Three Rivers Park District, the homeowners’ request to gate the ramp when inspectors are not present was turned down because it was inconsistent with park and DNR policies. Three Rivers officials said they welcomed more volunteer inspectors.

A gated approach at the Christmas Lake boat ramp is worth trying, said Steve McComas, owner of Blue Water Science in St. Paul who specializes in lake and watershed management. The boat ramp owned by Shorewood is the only publicly owned piece of property on Christmas Lake.

“I wouldn’t say I would like to see this on every single lake, but it certainly is a noble experiment. Why not try it and see what kind of problems we incur and see if it works?” McComas said.

Said Shneider: “We seem like a wonderful pilot because we do only have one boat ramp and the water quality is so good. If you are going to protect things, gosh, protect the best.”

Christmas Lake homeowners use the ramp to put their own boats in the water, Shneider said.

Shorewood, which operates the ramp under an agreement with the DNR, supported the watershed district’s application for a grant to pay on-site inspectors for the ramp, but the City Council has not addressed the gate idea, said city administrator Brian Heck.

“One of my questions is: Do we know for certain that there aren’t zebra mussels there already,” Heck said.

The watershed district is taking samples in the lake to find out.

Can Zequanox halt zebra mussel proliferation in Alexandria area lakes and beyond – and will it be safe?

Zebra mussels pillage lakes and rivers, devouring small organisms and algae through their efficient filtering systems. They are able to affix themselves almost like glue to objects, clogging pipes and creating swimming hazards. The Douglas County Lakes Association invited Dr. Daniel Molloy, a retired scientist from the New York Museum Cambridge Research Institute, to visit Alexandria area lakes and discuss a possible solution to the zebra mussel proliferation – a biopesticide called Zequanox.

By: Wendy Wilson, Alexandria Echo Press

Zebra mussels pillage lakes and rivers, devouring small organisms and algae through their efficient filtering systems. They are able to affix themselves almost like glue to objects, clogging pipes and creating swimming hazards.

The Douglas County Lakes Association invited Dr. Daniel Molloy, a retired scientist from the New York Museum Cambridge Research Institute, to visit Alexandria area lakes and discuss a possible solution to the zebra mussel proliferation – a biopesticide called Zequanox.

Molloy and a colleague discovered the bacterial strain pseudomonas fluorescens was able to kill the mussels. Pseudomonas fluorescens is the active ingredient in Zequanox.

Molloy has studied zebra mussels for more than 20 years. He became involved in researching the mussels in 1991 when companies were using bleach to combat the mussels in clogged pipes.HIGH HOPES

“We have taken the stance that doing nothing is not acceptable,” said Bonnie Huettl, Douglas County Lakes Association president.

The bacteria used in Zequanox are common and can be found inside refrigerators or on rugs, according to Molloy.

“It is omnipresent everywhere,” he said. “It is already in the lakes and that is because it lives in soil, and its job is to protect plants roots.”

The scientists at the research institute discovered zebra mussels died after consuming the bacteria, according to Molloy.

“It was serendipity, luck, persistence,” he said of the discovery. “We fed it to zebra mussels and quagga mussels, their cousins that cause problems, and it kills them.”

Marrone Bio Innovations is the commercial developer of Zequanox. In collaboration with the Douglas County Citizens’ Committee on Zebra Mussels (DCCC) and the Douglas County Lakes Association, Marrone provided a research request to the Minnesota DNR June 1 to evaluate the use of Zequanox in local lakes. The application has been delayed due to the Minnesota government shutdown, according to Huettl.

Marrone Bio seeks to test Zequanox in Lakes Carlos, Darling and L’Homme Dieu.

“This whole thing is very pioneering,” Molloy said.


Small scale testing using Zequanox in power plants has been conducted with larger-scale trials starting this summer, according to Molloy.

“So this cutting edge is part of why we were getting involved in it,” Huettl said. “We should go forward with it while we have the chance.”

Testing would begin with jar assays in a laboratory-type setting using a cloud of Zequanox and then graduate to the implementation of larger aquaria. Eventually, they would isolate a pile of rocks in a lake, to see if Zequanox kills the mussels.

“I call it baby-steps of research,” Molloy said.

Molloy and Dick Osgood, a certified lake manager, discussed the application of Zequanox.

“One of the challenges to open water is how do you apply it if the zebra mussels are on these rocks,” Molloy said. “Research has to be done to find a very efficient, cost effective and efficacious delivery system to get a little cloud down there for… like six hours.”

A granular blanket of Zequanox could be employed, according to Molloy. A delivery system that would allow the Zequanox to stick to the articles covered with the mussels also might be a possible solution, Osgood suggested.

The DCCC anticipates approval of the proposal from the DNR and the committee hopes to raise money to pay for the research.

Huettl estimates an initial cost of $300,000. DCCC plans to initiate a fund-raising campaign and is looking for private investors to help finance the project.

The group hopes Zequanox will be registered by the Environmental Protection Agency (EPA) for use in pipes later this summer and testing to begin in open waters next year.

“Getting the testing done is a start,” Huettl said. “The point is to get it started here in Minnesota and we would be the leaders, being that we have a number of lakes that need to be protected and nothing has been done to date.”


After testing is conducted in the lake, Molloy and Huettl expect the Zequanox would be allowed to disperse into the rest of the lake. They also do not anticipate the lakes would be closed during this period.

Molloy said dead bacterial cells would be used to combat the mussels, but a higher density of cells would be required.

“It kills [the zebra mussels’] digestive gland,” he explained. “Whether the cell is live or dead has no bearing on it because it is intoxication. It is not infection.”

Osgood said Zequanox would be reviewed thoroughly by the EPA.

“In my opinion, this stuff is safe,” he said. He later clarified his belief that after the EPA granted its approval for Zequanox applications in the lakes, it would be safe for humans.

But live pseudomonas fluorescens may wreak havoc on some humans, such as those that are immunocompromised, according to recent studies. The question is, will dead bacteria also affect humans?

Some community members were skeptical about Zequanox, although most were positive, according to Huettl.

“Being active and putting [Zequanox] into the lake has raised the hackles more so than what they do on their lawn spraying weed killer and those kinds of things,” she said. “You see permits all over the lakeshore for killing 50 feet of weeds. They don’t think anything of it, but, oh, put Zequanox in to kill a zebra mussel and, oh, my God, we’re poisoning the water.”


The DCCC is looking into the possibility of bringing in a company to make Zequanox here.

If a manufacturing plant was built in the Alexandria area, it could produce Zequanox for other lakes.

“We are looking at this as an entrepreneurial adventure, for someone here in Minnesota,” Huettl said. “Doing nothing is old news.”

Osgood agreed.

“Doing nothing has impacts,” he said. “I don’t think this chain of lakes has seen the full impact yet of zebra mussels. It is very early in the infestation.”

Osgood is executive director of the Lake Minnetonka Association. Zebra mussels were first discovered in Lake Minnetonka last July in small quantities.

“This year they are on virtually every rock,” he said. “They are exploding.”


“This is it,” Huettl said. “The chemicals that are out there that would be used are much more harmful.”

“The risks are so much higher,” Molloy added. “You’ll never eliminate risks. Every pesticide has risks.”

And Osgood said, “This is the only game in town. There really is nothing else.”

See upcoming issues of the Echo Press for more information about zebra mussels and safety concerns.