Douglas County Sees Further Spread of Aquatic Invasive Species

Douglas County officials say a troublesome aquatic invasive species was detected in a new body of water in samples taken over the summer.

The sample was taken from Upper St. Croix Lake in Solon Springs in July. Last week, officials announced that the sample had revealed the presence of zebra mussel veligers, which are the second larval stage of the invasive zebra mussels.

Zebra mussels were first detected in the county in 1989, and Upper St. Croix Lake is the third body of water they’ve been detected in. They are also found in the St. Louis River Estuary and Lake Superior. The invasive species is native to Europe and can deplete the food supply for other aquatic creatures if allowed to spread.

Officials say while the invasive species was detected in the sample, it was detected in low concentration. According to a Superior Telegram report, Douglas County Surface Waters Program officials say zebra mussels need certain environmental and water conditions to thrive so the low concentration is a good sign.

The Department of Natural Resources encourages residents to follow their guidelines to prevent further spread of the zebra mussels. Their prevention strategy asks residents to inspect their boats and equipment for the species after use and allowing at least 5 days for them to dry before being used in a different body of water.

Managing invasive species has been a major focus for the Northwest Wisconsin region in recent years. In addition to zebra mussels, Douglas County has also worked to prevent the spread of the invasive emerald ash borer. The beetles spread to Burnett County last summer, meaning every county in the state has now been infected.

Officials will continue monitoring the zebra mussels to prevent them from spreading to the over 400 other waterbodies in the county.