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BIOLOGY

How will zebra mussels affect the way I use lakes?

With zebra mussels present, you’ll have to be sure to drain the water from your motor, boat bilge, live wells and bait wells, and clean the weeds from the boat, motor and trailer before leaving the boat ramp.

As zebra mussels become more abundant in our lakes, they may also affect swimming areas. You will probably have to wear foot protection, such as sandals or water socks, when swimming or wading in order to protect your feet from the sharp edges of the shells. Back


Will zebra mussels change fishing?

Yes, because zebra mussels impact food webs, which directly impact the fish you may be angling for.

As they feed, zebra mussels deposit feces and regurgitated food on the bottom of a lake. These substances become food for bottom-dwelling worms, scuds, insect nymphs and larvae, making those invertebrate forms more abundant. Some fish may respond to this change by increasing their benthic feeding or orienting to other prey that forages on the bottom. Also, as zebra mussels feed, they filter plant plankton from the water. This in turn makes the water clearer. Fish that are light-sensitive may seek deeper waters to find shelter from the penetrating rays of the sun. Back


So zebra mussels make the water clearer isn’t that good?

Zebra mussels make the water clearer, but not cleaner. Although people often associate clear water with clean water, many chemicals and contaminants are invisible when they’re dissolved in water.

As zebra mussels feed, they filter plant plankton from the water, making the water clearer. Fish that are light-sensitive may seek deeper waters to find shelter from the sun. As the sun penetrates deeper, aquatic plants can take root in more extensive areas than they did before zebra mussels moved into the area. Vegetation provides small fish with more places to hide and makes it more difficult for large predators to feed, so this can result in stunted fish populations and pose significant problems for boaters. Back

If you leave your boat in the lake all summer long, you are likely to find zebra mussels attached to submerged portions of the hull and motor when you pull it out of the water at the end of the season. These need to be scraped or cleaned off with a pressure sprayer. You may prefer to keep your boat out of the water on a lift or trailer between uses. Back


Will zebra mussels harm my property—especially my dock, swimming platform and trampoline?

Zebra mussels will accumulate on the submerged portions of nearly any substrate. But when zebra mussels die, they can be easily removed when docks and other substrates are removed for winter. Back


How will zebra mussels change swimming in the lakes?

As zebra mussels become more abundant, they will probably affect swimming areas by covering the bottom—and all surfaces—with shells. The shells are very sharp, making it necessary to wear foot protection, such as sandals or water socks, when you’re swimming or wading. Back

Anyone who draws water directly from a lake infested with zebra mussels needs to remove the piping at the end of the year. This will freeze out the zebra mussels. Zebra mussels are highly attracted to flowing water, like the water in intake pipes. Zebra mussels will quickly colonize and clog traditional intake screens, so they will not protect the piping from zebra mussel larvae. An alternative is to construct a sand filter and intake bed, so that zebra mussel larvae are removed before they enter the pump and intake pipes. Back


How can I dispose of the zebra mussel shells that accumulate on my shoreline?

One option is to compost the shells and use them as mulch in your garden. In areas without contaminant concerns, zebra mussel shells are a good source of calcium and can be used for soil enhancement.

But, in areas where there are high contaminant concentrations, zebra mussels can accumulate enough pollutants to raise concerns about the residual organic material associated with the shells. In that case, it would not be advisable to use the shells in a vegetable garden or even as landfill. Back

Although zebra mussels are edible, we strongly advise you not to eat them. They accumulate contaminants as they feed, and in areas of high contaminant concentrations, zebra mussels can accumulate enough pollutants to raise concerns for human consumption. Back


What should I do if I cut myself on a zebra mussel shell? Will I need a tetanus shot?

Although the shells themselves do not typically raise concerns, the mud and dirt they’re found in could be contaminated, so a tetanus shot is probably a good precaution. Back

Diving ducks and fish, such as sheepshead, common carp, redear sunfish and round gobies, eat zebra mussels. Though they may reduce the number of zebra mussels in a limited area, none of these animals will eradicate zebra mussels from a lake. Back


Are there any chemical controls for zebra mussels?

There are no known species-specific chemical controls for zebra mussels. Chemicals that kill zebra mussels also kill other, more desirable species. Back


What can I do to help prevent the spread of zebra mussels?

Boaters and other water users need to practice good boating hygiene: remove weeds from the boat, motor and trailer before leaving the boat ramp. Always drain water from your motor, boat bilge, live wells and bait wells. Back


I've heard you can get tickets in some states for not cleaning the weeds off your boat. Is that true?

Yes, some state departments of natural resources, including the Minnesota and Wisconsin DNR, have begun issuing tickets to people who do not practice good boating hygiene. Back