ST. PAUL - The list of northern Minnesota lakes with infestations of spiny waterfleas grew Thursday, when the Department of Natural Resources reported that the creatures have taken hold in Basswood Lake on the Ontario border.
Basswood, along with lakes and streams immediately downstream, will be added to the state’s list of officially infested waterways, with special regulations to prevent their spread.
The discovery was confirmed in zooplankton samples taken by the University of St. Thomas in partnership with DNR fisheries staff. Spiny waterfleas also were found in the stomach contents of Basswood Lake cisco.
The creatures already had been found on several border lakes, including Rainy, Lac La Croix and Saganaga.
Spiny waterflea is a small planktonic crustacean that disrupts the food web and competes with small fish as it forages on microscopic animal plankton such as daphnia. Because of its long tail spike, the spiny waterflea is not eaten by many species of fish.
ADVERTISEMENT
The creature first was found in the Duluth harbor in the 1980s and is believed to have hitchhiked in the ballast of ships from Europe. Their spread now is believed to be spurred by recreational anglers, boaters and others who inadvertently moved the creatures from one lake to another.
