Minnesota - Waterfleas found in state's lakes

[Hamilton Reef]

Remember once-upon-a-time when we could travel to remote muskie lakes to get away from the Great Lakes invasives problems? :(

Minnesota - Waterfleas found in state's lakes
Officials confirm sightings at seven sites

http://www.twincities.com/mld/pioneerpr ... 169141.htm

Aug. 01, 2006 BY DENNIS LIEN Pioneer Press dlien@pioneerpress.com or 651-228-5588

Spiny waterfleas, a pesky nonnative species that has been moving into northern Minnesota lakes, were found recently in Voyageurs National Park on the Minnesota-Ontario border, federal officials say.

A Duluth teenager vacationing on Rainy Lake found more than a dozen of them on his fishing line July 18 while trolling for walleyes off the park's Blueberry Island. National Park Service officials then confirmed them at seven sites on the U.S. side of the lake, increasing the likelihood they'll spread downstream to Lake of the Woods, a popular fishing destination.

Masses of quarter-inch-long waterfleas can resemble gelatin with tiny black spots, which are the creatures' eyes.

They were discovered in the United States in Lake Ontario in 1982 and in Lake Superior in 1987, likely arriving in the ballast of ships from Eastern Europe. They have since been found in Boulder, Island and Fish lakes near Duluth, and in Saganaga, Greenwood, Pine, McFarland, Seagull and Flour lakes near the Gunflint Trail — probably moved about by unsuspecting anglers in boats or bait buckets.

Though they eat the same zooplankton as small fish and can foul fishing lines, their impact so far has been hard to assess.

"The effects on any given body of water are going to be different just because you have a different suite of species interacting under different water conditions,'' said Steve Windels, terrestrial ecologist for Voyageurs National Park.

Native fish generally won't eat them because of their long spiny tails.

The Minnesota Department of Natural Resources is working to designate Rainy Lake an infested water, making it illegal to transport water or bait from the lake. Anglers and boaters are asked to drain and clean boat bottoms, bilges and bait buckets and let them dry between trips.