Eurasian watermilfoil found; capable of choking out native species

For several years, the Kansas Department of Wildlife and Parks (KDWP) has warned the public about the dangers aquatic nuisance species (ANS) pose to native aquatic wildlife and plants. The campaign started when zebra mussels invaded the Midwest, finally infesting El Dorado Reservoir.

Recent issues of the Kansas Fishing Regulations Summary have devoted two pages to other invasive aquatic species that threaten native species and their habitats. Currently, these include two mollusks (zebra mussel and New Zealand mud snail), two fish (Asian carp and white perch), and three plants (purple loosestrife, saltcedar, and Eurasian watermilfoil).

Until now, the New Zealand mud snail and Eurasian watermilfoil had not been detected in Kansas waters, but the recent discovery of Eurasian watermilfoil in eastern Kansas has biologists concerned. The aquatic plant has been found in Yates Center City Lake, in central Woodson County, and Lebo City Lake, in northwestern Coffey County. The plant forms dense mats on the surface of water, reproduces by fragments that can be transported by boaters, and forms a dense canopy that hinders recreational boating and fishing. In addition, the plant can grow 30 feet deep, shading out native vegetation and reducing oxygen levels during decomposition.

In addition to destroying native habitat, the pervasive "jungle" created by Eurasian watermilfoil makes it difficult for predator fish species, such as largemouth bass, to find prey.

"When this plant takes over, you'll be lucky to find predators longer than 10 inches," says KDWP aquatic nuisance specialist Jason Goeckler, Emporia. "It can ruin fish habitat, so we need to stay on top of it."

This may not be easy, according to Goeckler, who is working with local city governments and the Kansas Department of Health and Environment to develop a strategy to deal with the plant.

"One problem is that the Yates Center lake is the city's water supply," says Goeckler. "We'll have to approach this carefully and stay on it for at least three years before we see success in controlling it. Right now, it's widespread around the boat ramp, which is particularly problematic." Goeckler calls attention to the boat ramp because boats can be one of the primary means of spreading the plant to other waters.

Eurasian watermilfoil and other ANS are non-native species that threaten the ecological stability and economic viability of Kansas water resources. Once ANS are introduced, their control is very difficult if not impossible. There are several major pathways through which ANS are introduced, but most are the result of human activities, both intentional and unintentional. To prevent the spread of Eurasian watermilfoil and other nuisance species, follow these steps:

• empty bait buckets on dry land and never dump bait into a lake from which it is not taken;
• never move fish caught from one body of water to another;
• inspect boats, trailers, anchors, duck decoys, waders, and other equipment and remove any visible organisms, vegetation, and mud;
• wash equipment with 140-degree water, a 10-percent chlorine and water solution, or a hot saltwater solution if exposure to ANS is suspected;
• drain all water from boats and equipment before leaving a water body;
• do not release aquarium pets or anything from an aquarium into or near a body of water or storm drain. Bury them or freeze and dispose of them in the trash.

It is illegal to release exotic species into the waters of the state. Phone KDWP's Emporia Research Office at 620-342-0658 or any local KDWP office if any aquatic nuisance species are found.

-30-

Back to November 2006 News