April 30, 2007
Aquatic hitchhikers in area ready for fishing opener May 12
By Roz Kohls
Some of the Dassel Cokato area lakes will appear inviting during the fishing opener May 12, but watch out. They have Eurasian watermilfoil in them, an aquatic hitchhiker waiting to be carried to other lakes.
Eurasian watermilfoil, myriophyllum spicatum, is an invasive species of plant that can interfere with boating, fishing and swimming. In nutrient-rich lakes it forms thick underwater strands of tangled stems, and vast mats of vegetation at the water’s surface.
A single segment of stem and leaves can take root and form a new colony. Fragments clinging to boats and trailers can spread the plant from lake to lake.
So, after having fun fishing in Lake Washington, confirmed infested by Eurasian watermilfoil in 1999, and Waverly, Rock, Howard, Clearwater, and Augusta lakes especially, check your trailers and rinse out your boat’s live well, according to Assistant Manager Eric Altena of the Montrose area fisheries.
Use bleach, if possible, in live wells after fishing in those lakes.
There are other area lakes that are infested also, and listed in an April 2006 report, according to William Rendall, Minnesota DNR invasive species program coordinator.
In Meeker County they are Lake Manuella, Ripley Lake, Stella Lake and Wolf Lake.
In Wright County, they are French, Beebe, Buffalo, Clearwater, Deer, Fish, Little Waverly, Ramsey, Mink, Indian, Goose, Sugar and Weigand Lakes, as well as Lake Mary, Lake Pulaski and Clearwater River.
Eurasian watermilfoil has difficulty becoming established in lakes with well-established populations of native plants. Also, in some lakes, the plant appears to coexist with native flora and has little impact on fish and other aquatic animals.
In nutrient-rich lakes, especially shallow areas, the plant’s floating canopy can crowd out important native water plants and interfere with water recreation, according to the Minnesota Department of Natural Resources.
In Minnesota it is illegal to transport harmful invasive species. If you are a boater, angler, water-skier, or canoeist, here are things you can do to prevent the transport of Eurasian watermilfoil and other invasive species:
• Inspect your boat, propellers, keels, rudders, trailer, anchors, centerboards, rollers and axles.
• Remove any plants and animals that are visible before leaving any water body, even if you are unsure whether the lake is infested.
• Drain water from the motor, live well, bilge and transom wells while on land before you leave any water body, even if you see no plants or animals.
• Dispose of unwanted bait in the trash. Never release live bait into a water body, or release aquatic animals from one water body into another.
• Wash, then dry your boat, tackle, downriggers, trailer and other boating equipment to kill harmful species that were not visible at the boat launch. This can be done on your way home or once you have returned home.
Some aquatic nuisance species can survive more than two weeks out of water.
• Rinse your boat and equipment that normally get wet with hot (at least 104 degrees F) tap water, or spray boat and trailer with high-pressure water, or dry boat and equipment for at least five days before transporting to another water body.
• Learn what Eurasian watermilfoil looks like. Eurasian watermilfoil typically has 12 to 21 pairs of leaflets. The native northern watermilfoil, with which it is often confused, has five to nine pairs.
The mechanical clearing of aquatic plants for beaches, docks and landings creates thousands of new stem fragments. It is possible to transport Eurasian watermilfoil without seeing a full stem of leaflets.
Eurasian watermilfoil was accidentally introduced to North America from Europe. It spread westward into inland lakes primarily by boats, and reached Midwestern states between the 1950s and 1980s.
Eurasian watermilfoil was first discovered in Lake Minnetonka during the fall of 1987.
Don’t let the infestation of Eurasian watermilfoil in area lakes spoil your fishing plans, though. Lake Washington, for example, is one of the “Super Seven” walleye lakes in the area on opening day, according to the DNR Fisheries office in Hutchinson. It is shallow, so it warms up fast, and it is well-stocked, said Chris Schultz in “Outdoors” of the Herald Journal.
Howard Lake also is infested with Eurasian watermilfoil, but is due to produce both good walleye and northern pike action, he said.
Zebra mussels in Wright County
Zebra mussels, another invasive species, have infested Fish Lake in northern Wright County, according to a 2006 report from the Minnesota DNR’s Invasive Species Program Coordinator, William J. Rendall.
Zebra mussels, Dreissena polymorpha, also are in the Mississippi River, said Eric Altena, assistant area fisheries manager in Montrose.
They are fingernail-sized freshwater mollusks. They get their name from the striped patterns on their shells, although not all zebra mussels have stripes.
Fish Lake is in Clearwater Township, near the Sherburne County border.