Zebra mussels have been found in Pelican Lake in Otter Tail County
Zebra mussels have been found in Pelican Lake, bringing new regulations to bear on those who use the lake, and raising concerns of mussel infestation through the Pelican, Ottertail and Red river chains all the way to Lake Winnipeg.
It marks the first time the mussels have been confirmed in the area and in the Red River Basin.
A non-native invasive species, zebra mussels pose serious ecological and economic threats to Minnesota's lakes and streams.
Heavy infestations can kill native mussels, impact fish populations, interfere with recreation, and increase costs for industry, including power and water supply facilities.
Much smaller than the native mussels, zebra mussels are a quarter-inch to 1 ½-inches long and are D-shaped with alternating black and brown stripes.
"Zebra mussels are tricky to find when they are larvae, because they are not visible to the naked eye," said Moriya Rufer, lakes program coordinator for RMB Environmental Laboratories, Inc., of Detroit Lakes.
Rufer said a resident of Pelican Lake called her after finding what appeared to be a zebra mussel attached to a native mussel.
Rufer and some DNR biologists "went scuba diving" in Pelican Lake looking for confirmation, she said, and found both adult and young zebra mussels -- suggesting that they have been in the lake for more than a year.
She urged lake residents to examine their docks and boatlifts when they bring them in for the season, and to notify the DNR if they find zebra mussels clinging to those surfaces.
"They'll be looking in Lake Lizzie next, since it's directly downstream from Pelican lake," she said. "Pelican exits to Lizzie, then to Prairie Lake, to Pelican Rapids, and joins the Ottertail River near Fergus Falls."
The Ottertail joins the Bois de Sioux River to form the Red River of the North at Breckenridge, and the Red River flows north all the way to Lake Winnipeg.
Because zebra mussels spread as invisible larvae, it is easy to inadvertently help them move from lake to lake.
"The larvae can live in your live well if there is water there, and then spread to other lakes," Rufer said. "This could be how they entered Pelican Lake."
"Zebra mussels could pose risks for other waters," said Nathan Olson, DNR invasive species specialist in Fergus Falls. "Pelican Lake is connected to several other lakes and has significant boat traffic. Everyone needs to be extra vigilant to keep from spreading these pests to other waters."
The DNR will continue to search for zebra mussels in connected waters, especially downstream of Pelican Lake.
This is the fifth new Minnesota lake to be identified as infested with zebra mussels this year.
While there are no control methods to eliminate the zebra mussels from Pelican Lake, the DNR will take action to help prevent the spread of zebra mussels to other waters that are not connected to the lake.
The actions include:
The DNR will designate the lake and nearby portions of the Pelican River as zebra mussel infested waters, which makes some activities illegal, such as transporting water and harvesting bait.
Signs will be posted at the public water accesses on the lake to notify boaters that it is infested with zebra mussels and new regulations apply.
The DNR, in conjunction with the Pelican Group of Lakes Improvement District (PGOLID), has been conducting inspections of boats on Pelican Lake for several years, and will continue to inspect boats on the lake and downstream lakes that may become infested.
Enforcement of invasive species laws and efforts to raise public awareness around the lake will increase.
Under Minnesota law it is illegal to transport zebra mussels, aquatic plants, and water from designated infested waters.
Native to Eastern Europe and Western Russia, zebra mussels were first discovered in Minnesota in 1989 in the Duluth harbor.