The Minnesota Department of Natural Resources (DNR) has confirmed that zebra mussels have been found on opposite ends of the Whitefish Chain of lakes - in Lower Hay lake on the west and Cross Lake on the east.
Dan Swanson, Brainerd area DNR aquatic invasive species (AIS) specialist, said Tuesday, July 16, that crews would be out searching other areas of the chain for the zebra mussels. He said that it’s likely all lakes in the chain are infected, but as of July 16 the mussels had only been found in Lower Hay and Cross.
Swanson said that the mussels found in the lakes were adults, meaning that they’ve been there for at least a year.
Conservation officer Nikki Shoutz said the Cross Lake mussels were found at a private residence on Moonlite Bay. When the DNR went to the residence, staff members spent an hour and a half searching but didn’t find any more zebra mussels, Swanson said.
But, when the DNR returned during better conditions, a zebra mussel was located in the area in about three feet of water, attached to a branch.
Swanson said the team then decided to inspect other areas of the chain, including Lower Hay where the other specimens were found. Nothing turned up on Daggett or Little Pine, but Swanson said this could have been due to poor searching conditions, and doesn’t mean there aren’t zebra mussels in those lakes.
The mussels were confirmed in Cross Lake by the DNR on Tuesday, July 9, Shoutz said. It was Friday, July 12, when the zebra mussels were found in Lower Hay Lake, on the opposite side of the Whitefish Chain.
“Friday was a big discovery,” Swanson said. “That was a big find because it puts zebra mussels on both ends of the Whitefish Chain.”
He said he planned to do more inspections and plankton sampling to see if there were any veligers (immature, microscopic zebra mussels) in the water.
“There’s a definite population out there,” Swanson said, but he did note that the population is an early establishment.
Signs have been placed at every public access of the chain, notifying boaters of the presence of the zebra mussels.
The resounding response from area associations and authorities is that inspections at accesses will continue at full strength.
Dave Fischer is president of the Whitefish Area Property Owners Association (WAPOA). He noted that just because boaters will see the signs about zebra mussels at all public accesses, it doesn’t mean they’ve been confirmed as present in that lake.
“Obviously we were disappointed that zebra mussels have made it into the chain,” Fischer said. “I think the message, for us, is we’re going to keep our inspections up. There are other invasive species out there we need to be on guard for.”
Alan Sherburne, AIS specialist for WAPOA, said that there are more than 100 invasive species for public access boat inspectors to watch out for. WAPOA uses grants from the DNR as well as dues from members to fund paid inspectors, as well as volunteers, to monitor boats at accesses for invasives.
He said WAPOA has coordinated 2,600 hours of work this year at public accesses, inspecting for invasive species.
Steve Curry, president of Friends of Lower Hay Lake Association, said that the inspections his organization coordinates will also move forward as planned in order to keep out other AIS. He remarked that he was glad the mussels were kept out as long as they were, given the amount of use the lake gets and the number of area lakes that are infected.
“We felt good that we had held them off until now,” he said.
Corrine Hodapp, supervising park ranger at the Army Corps of Engineers (COE) Campground on Cross Lake, said the corps is evaluating what additional things it can do now that zebra mussels have been found in the lake.
She said that the COE partnered with other agencies to purchase a decontamination unit after zebra mussels were found on Gull Lake, but plans haven’t yet been formulated to do that at Cross Lake.
Swanson said that it’s hard to say just how the population of mussels will progress in the chain. He said it depends on factors like water quality.
“It’s hard to say, will there be an impact or not? We’ll know five or 10 years down the road,” Swanson said, noting that there simply isn’t enough known about the mussels to predict how things will progress. “We’re going to find out if the mussels will take a liking to the lake.”
Zebra mussels are known for their ability to reproduce. Females lay up to one million eggs a year. The mussels attach to docks, boat hulls, rocks and native mussels. Because of their sharp shells, they can cut the feet of swimmers in the lake.
Other area lakes that are designated by the DNR as water infested by zebra mussels include Pelican Lake, Ossawinnamakee, Nisswa Lake, Round Lake and the Gull chain of lakes. In a press release, the DNR stated that Big Pine Lake will also be listed as infested, because it is downstream from Cross Lake. The area of the Pine River, upstream from its confluence with the Pelican Brook (which is already listed as infested) to the Cross Lake dam will also be added to the list.
More information on zebra mussels is available at www.dnr.state.mn.us/invasives.