Montana Fish, Wildlife and Parks and partners this year intercepted more than twice as many boats carrying invasive mussels as any other year.
During a virtual summit Wednesday, Thomas Woolf, aquatic invasive species bureau chief with FWP, said the majority of the 35 mussel fouled boats came from the Midwest, including a sailboat with live mussels headed for Coeur d’Alene.
“The majority of those were recently purchased. So people are buying them. They’re contracting a hauler to move them out here or they’re actually taking a drive to pick up a boat and bringing it back, which is a problem if the boat’s in the water. They test drive the thing, they load it up on the trailer and it’s in Montana in two days," Woolf said.
Woolf said watercraft inspectors found mussels on some boats that were supposedly decontaminated before coming to Montana.
“These mussels like to hide, that’s in their very nature. They’re in the hardest places to find, usually is where they set up shop first," he said.
Invasive quagga and zebra mussels coat surfaces with razor-sharp shells, block irrigation pipes and steal food from native fish. Currently, there’s no silver bullet for eradicating mussels once they become established.
FWP, conservation districts, tribes and national parks in a coordinated effort to stop hitchhiking mussels broke a record this year with 175,000 watercraft inspected in Montana.
AIS prevention coordinator Zach Crete said part of the reason for that high number has to do with a change in record keeping.
“So for example, you might have a jet boat coming and it might have two kayaks and a paddle board in it. So instead of one inspection record, there’s four for that. So that pushed our numbers up," Crete said.
But even in an apples to apples comparison with previous years, check stations were busier than ever in 2020.
“Folks sticking around in Montana and recreating here on the water because of COVID-19 restrictions on travel," Crete said.
FWP also had more targeted law enforcement, especially around Anaconda.
The agency’s Enforcement Division gave out 268 citations to people who drove past watercraft check stations, along with 308 written warnings.
Woolf said the bureau is working closely with Midwestern states to find ways to make sure boats are properly cleaned, drained and dried before heading west, as well as neighboring states to better coordinate data sharing and prevention.
“Seeing mussel distributions expand in the Dakotas is a reason for concern. The closer they get to Montana, the more likely it is that we get them," Woolf said.
People transporting motorized and non motorized watercraft are required to stop at all open inspection stations; those coming from out of state must purchase a Vessel AIS Prevention Pass and get inspected before launching.
To Find a watercraft inspection station and to learn more, go to CleanDrainDryMT.comor call the FWP Aquatic Invasive Species Bureau at 406-444-2440.
Craig McLane, AIS detection and monitoring coordinator, said field crews did not find mussel populations this year after surveying more than 1,900 sites across the state. That includes the Tiber Reservoir where quagga and zebra mussel larvae were detected in 2016.
“Everybody’s always interested in Tiber, right? So we kind of threw all of our tools at it," McLane said.
Those tools include plankton and environmental DNA sampling, detection dogs at recreation areas, a tool that scrapes the bottom of a lake to pick up sediment and a diving team that checked the highest risk locations for invasive mussels.
“So with all that sampling, we still have no positives. It was great. Even the e-DNA came back negative," McLane said.
But new populations of other invasive aquatic species were found this year, including curlyleaf pondweed at the Lower Glaston Reservoir north of Big Timber and Deadman’s Basin east of Roundup and the faucet snail near Whitefish at Smith Lake and the recently renamed Lost Loon Lake.
The New Zealand mudsnail was found at the Bluewater Fish Hatchery near Bridger, Marias River below the Tiber Reservoir, Rainbow Reservoir near Great Falls and Spring Meadow Lake near Helena.
Spiny water nymph was found at two ponds near Frenchtown.
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