Defenders of the Seeley-Swan hunt invasive mussels, weeds with boat checks

A watercraft inspector with Montana Fish, Wildlife and Parks inspects a canoe before it hits the water in the Seeley-Swan Valley on Independent Day. (Martin Kidston/Missoula Current)

They arrive as canoes, jet skis, motor boats and paddle boards, each looking for a clean bill of health from Denise Richardson and her team of seasonal employees with Montana Fish, Wildlife and Parks.

Set up on the corner of Highway 200 and Highway 83, the state inspectors serve as guardians of the Seeley-Swan Valley, looking to block the arrival of invasive aquatic threats, from zebra mussels to Eurasian water millfoil.

“We’re preventing the movement of aquatic and invasive species, including zebra mussels and weeds,” Richardson said Tuesday. “The important thing is to keep things dry.”

Stopping at inspection stations such as this is no longer voluntary in Montana, and roadside signs clearly state the mandate. More than 300 watercraft arrived on July 2, followed by 200 more on July 3.

Late last year, Tiber and Canyon Ferry reservoirs – both east of the Continental Divide – tested positive for the larvae of aquatic mussels. That prompted the state to adopt emergency restrictions in an effort to keep the mussel from spreading to uncontaminated water bodies in the state.

For Richardson and three other inspectors working the station on Independence Day, the threat of contamination extends beyond the mussel. It also includes the New Zealand mudsnail and a host of plants, including the fragrant waterlily and the curlyleaf pondweed.

“If the weeds stay wet, they could be moved from lake to lake, or water to water, so we’re hoping people remove them from their boats,” said Richardson. “The main thing is standing water this year. Young mussels can also be moved in water and can’t be seen. The important thing is to keep things dried, cleaned and drained.”

Richardson and her team work from the shade of a camper trailer parked at a truck stop along the intersecting highways, not far from the Clearwater and Blackfoot rivers.

But it’s the chain of lakes to the north that generates much of this weekend’s traffic – Salmon, Seeley, Holland, Inez, Placid and others. The popular destinations help feed a multi-million dollar recreation economy, one that could be damaged if the invasive species were to spread.

The lakes in the Seeley-Swan Valley were crowded with boaters over the Independent Day weekend, including Salmon Lake. (Martin Kidston/Missoula Current)

According to one state expert, if left unchecked, the mussels could also suffocate valuable fisheries in a region that depends on environmental tourism. That says nothing of the ecological damage that could unfold across the Columbia River Basin if the species found their way across the Continental Divide.

Add it all up and it’s reason enough for Richardson to spend her holiday weekend inspecting watercraft, never mind the blazing sun.

“We take it seriously,” Richardson said. “For me personally, I think it’s important to stop the movement of anything invasive, and just to keep things clean.”

Starting in April, the state implemented watercraft inspection stations, calling it “perimeter defense” for the upper Columbia basin.

That includes watercraft crossing the Continental Divide into western Montana – something of interest for down-river states including Washington, Oregon and northern Idaho.

“It’s important to me – we don’t need those mussels coming up here,” said one man. “We’re doing our best to keep them out.”

Contact reporter Martin Kidston at info@missoulacurrent.com