Glacier issues temporary boating closure

Glacier National Park implemented a temporary boating closure on all waters within the park Thursday, one day after Montana Fish, Wildlife and Parks announced the first-ever detection of invasive mussels in state waters.

The closure is part of Glacier’s aquatic invasive species action plan, which went into effect after the presence of mussel larvae was confirmed in the Tiber Reservoir, about 75 air-miles east of the park near Shelby. Glacier’s fisheries program manager, Chris Downs, said Thursday that the closure will likely extend well into next year.

“We’d like to see some more testing around the state in 2017, including park waters, and take a more thoughtful approach to addressing the threat it poses,” Downs said. “You look where Glacier National Park is, it’s on top of the continent and it’s not only critical to protect the park’s ecosystems — if it’s established in some park water body, everybody downstream would be at risk.”

Glacier straddles three major North American watersheds, including headwaters that flow to the Columbia, Missouri and South Saskatchewan river basins.

Downs noted that new water samples will be unable to confirm the presence of mussel larvae until waters warm up next year. Those larvae, or veligers, require water temperatures to reach at least 52 degrees, according to state fisheries division administrator Elieen Ryce.

No waters within Glacier’s boundaries have ever tested positive for mussel contamination, but Downs noted that the park is still awaiting test results from samples taken from high-use bodies of water within the park this past summer.

“We haven’t gotten our results back, but we don’t anticipate anything,” he said, noting that visual inspection of shorelines, docks and piers had not indicated any presence within the park. But he added, “It just seems like a really big jump from no (mussel contamination) in the state of Montana to Central Montana.”

Glacier spokeswoman Lauren Alley said park officials will be in contact with Montana’s fish and wildlife agency as state biologists continue testing water samples from other parts of the state to determine the extent of mussel contamination.

While Glacier Park share jurisdiction over the North Fork of the Flathead River and Waterton Lake, Downs said the closures would not affect those bodies of water, because public access is mostly controlled by other agencies. The Middle Fork is also outside the park’s jurisdiction.

THE PARK’S response comes as state fisheries managers grapple with the confirmed presence of invasive mussel larvae in the Tiber Reservoir, announced Wednesday along with a possible detection in the Canyon Ferry Reservoir near Helena.

The long-feared discovery of either zebra or quagga mussels (state officials have not yet determined which species) leaves a dwindling number of Western states that have successfully kept the bivalves from taking hold.

Stephanie Hester, the Montana Invasive Species Advisory Council Coordinator, said Wednesday there is a possibility the mussels may have not had a chance to establish themselves in the Tiber Reservoir, but she acknowledged the likelihood is slim.

In places where introductions have occurred, the two closely related mussel species are known for their rapid population growth that typically leaves their spread irreversible in large bodies of water.

Economic fallout often accompanies the ecological impacts, as the aquatic invaders clog pipes and damage irrigation, hydroelectric and municipal water infrastructure. They can also deter recreational use, as their sharp shells blanket public beaches and boats must undergo thorough cleaning after launching on infested waters.

Eradication “is a big question mark with these critters,” Downs said. “There’s only been a couple success stories on really small bodies of water using lots and lots of chemicals.”

The park’s invasive species action plan, finalized in 2014, outlines steps the park will undertake following a nearby mussel detection.

The plan calls for a “Tier 2 response” if invasive mussels are found within Montana. As National Park Service officials assess the potential for the bivalves to spread into Glacier’s waters, no boats — including hand-propelled watercraft — will be permitted to launch in park waters. The plan allows for a possible exception for boats operated by or rented from concessionaire companies within the park.

Although Glacier requires all motorized watercraft to be inspected for aquatic invasive species and certified by park officials prior to launching, hand-propelled watercraft, such as kayaks, are self-certified by individuals.

Downs said he and other park officials will re-think that policy before boat access to Glacier’s lakes and other waters resumes. But he noted that the park has few options available to beef up protection of its waters, short of continuing the boating closure.

“We’re going to focus on the closure right now and continue educational efforts, a ‘Clean-Drain-Dry’ message, and make sure folks are increasingly aware of how significant this issue is and how it has a real potential to effect them,” Downs said. “It’s not just a concern for other parks in other parts of the country anymore.”