LA CROSSE, Wis. -

For boaters heading out onto the Mississippi River over the weekend there are some areas you are being asked to avoid.

Tens of thousands of waterfowl travel through the Lake Onalaska area as part of their fall migration. For that reason the U.S. Fish and Wildlife Refuge is asking boaters to watch out for waterfowl resting and feeding on the Mississippi River.

During the migration season voluntary waterfowl avoidance areas, located on pools seven and eight of the river, are in effect to keep boats from disturbing the birds.

Boaters are asked to throttle down and steer around areas with large concentrations of birds, so they can spend their time preparing for the long trip south. "The goal is to keep the birds on these concentration areas where there are a lot of feeding opportunities and food available. What that does is give the birds enough energy to carry them through the rest of the migration into the wintering period," says Jim Nissen, manager of the La Crosse District of the Upper Mississippi River Wildlife and Fish Refuge.

Another reason for the voluntary avoidance areas is to spread the waterfowl over the 260 miles of the refuge. That allows for better feeding for the birds, and more opportunity for birdwatchers to see them.

Refuge officials say the number of disturbances in the avoidance areas have been on the rise in the past couple of years.

Boaters should be looking out for white buoys that serve as boundaries for the avoidance areas. The avoidance areas are located at Lake Onalaska, the Goose Island No Hunting Zone, and the Wisconsin Islands closed area.

Lake Onalaska's avoidance area is in effect through mid-November, while the others run into December.

You can find updated pool maps and other information at http://www.fws.gov/refuge/Upper_Mississippi_River/Fall_Flights.html.