Be careful about exotic hitchhikers

Exotic species are plants and animals that are not native to Minnesota.

Once introduced into our lakes and rivers, these unwanted aquatic invaders are very destructive and aggressive. They can choke up lakes with mats of plants, compete for food resources with game fish and attach to boats and docks.

The most common aquatic exotic species of concern in Minnesota are Eurasian watermilfoil and zebra mussels.

Eurasian watermilfoil now is found in more than 135 lakes in Minnesota, including Bay Lake, Ruth Lake, Ossawinnamakee Lake and the Ripple River between Bay Lake and Tame Fish Lake in Crow Wing County. Zebra mussels have been found in only one inland lake -- Lake Zumbro near Rochester -- but they are in many lakes in our neighboring state of Wisconsin. Once established, these species rarely can be eradicated.

These exotics commonly make their way to lakes and rivers as hitchhikers via boats and fishing gear. In fact, it is unlawful to transport aquatic plants on public roads or to place a watercraft or trailer with aquatic plants attached into the state's waters. Recently, a boat repair shop in Brainerd found zebra mussels on a boat that had come from the St. Croix River, where zebra mussels are present. Though they were dead after the boat was wintered over on land, the incident shows how possible it is for these exotic hitchhikers to make their way to the Brainerd area.

To help protect our waters and prevent the spread of these harmful exotic aquatic species, take the following precautions when transferring your boat from one waterbody to another.

1. Remove aquatic plants and animals from all parts of your boat, trailer and accessory equipment. Spots to pay special attention to on the boat are the axle, the lower unit of the motor, ski lines, anchor and other ropes, livewell, trailer rollers and the hitch area of the vehicle. Dispose of the removed material in the garbage at the water access area or at home.

2. Drain all water from your boat, including the bilge, livewell and other containers before leaving the water access.

3. Wash your boat and trailer thoroughly with regular water when you get home. Flush through your motor's cooling system, live wells and other areas that hold water.

4. Preferably, dry your boat and equipment in a sunny area for three days before using it in a new lake or river.

It only takes one careless boater to infest a lake. Remember--clean boats result in clean waters.

(This column is sponsored by the Crow Wing County Water Planning Board and the Minnesota Lakes Association -- www.mnlakes.org.)