Busy summer for aquatic invasive species prevention

It’s been a busy summer on the front to combat aquatic invasive species.

So far, Montana Fish, Wildlife & Parks and its partner agencies have conducted more than 52,000 watercraft inspections – with more than 7,000 of those happening over the Fourth of July weekend. To date, 13 vessels with zebra or quagga mussels have been intercepted.

Several new watercraft inspection stations opened in the last couple of weeks, including the Broadus inspection station on Highway 212, operated by the Powder River Conservation District. Also new is the St. Xavier inspection station on Hwy 313, operated by the Big Horn Conservation District. The Wibaux station on I-94 is now managed and operated by the Garfield Conservation District. •

More than 600 plankton tow samples have been collected across the state for mussel veliger (final larval stage) early detection analysis. FWP’s AIS lab has processed 522 of those samples, and no zebra or quagga mussel veligers have been detected to date.

After signs of Asian clams were found at Lake Elmo in Billings, AIS staff conducted a thorough survey of the lake and discovered several live clams. A further delineation survey of the lake, the canal system and other connected waters is currently under way. Next steps will be determined following the survey. Asian clams do not stick to things and their impacts are not quite like zebra or quagga mussels.

The Flathead Biological Station in partnership with FWP, will be conducting an intensive survey in areas of Tiber Reservoir in early August. The survey will utilize both molecular (eDNA) and microscopy methods in an attempt to get a better picture of whether invasive mussels are still in Tiber Reservoir and where they are located. No evidence of invasive mussels was found in Tiber in 2018. Forty-five plankton tow samples have been collected and analyzed so far for Tiber this season and no mussel veligers have been detected.

FWP reminds recreationists that a new law requires motorboats with ballast and bladder bags to be decontaminated when transported into Montana from out of state or when traveling west across the Continental Divide.

In AIS news from our neighbors, mussels have jumped more than 100 miles upstream in the Missouri River: Lake Sharpe, S.D., is positive for zebra mussels. A new zebra mussel population was detected in Lake Ashtabula, N.D. Colorado is also seeing challenges with mussels on boats from Lake Powell.

FWP staff have developed a new way to display watercraft inspection data. In the near future, inspection data will be available to view online.