Under Siege

One of the most devastating invasive species in the world has arrived at the gateway to the Flathead Basin, posing ecological and economic consequences that could imperil the pristine watershed forever

By Tristan Scott
An angler tries his luck near Somers on Flathead Lake on Dec. 2, 2016. Greg Lindstrom | Flathead Beacon

This is not a drill.

Those five words have become a familiar if eerie refrain to research scientists and state management agencies since the Nov. 8 discovery of destructive mussel larvae in Tiber and Canyon ferry reservoirs east of the Continental Divide, marking the first time the invasive species have been detected in Montana waters and pulling a dire scenario into grisly focus.

As state officials, stakeholders and independent research institutions deploy resources to combat an aquatic enemy at the gates, the future remains uncertain.

An infestation of zebra or quagga mussels could spell the beginning of the end for Montana’s most pristine watersheds, holding the potential to topple underwater food webs that prop up the Treasure State’s prized aquatic species while wreaking untold havoc on its infrastructure and recreation economy.

“This is a huge deal. We have been bracing ourselves for this for a long time and hoped it would never happen,” Tom Bansak, assistant director of the Flathead Lake Biological Station, said. “Well, it’s here, it’s now, it’s real, and the only possible chance of getting rid of them is finding them early and in a localized area.”

So far, the traces of contamination are restricted to the Missouri River Basin, but the likelihood of mussels hitchhiking on the hulls of boats or in bilge water or cloistered away in irrigation equipment has risen to a fever pitch. The threat of mussel infestation hits especially close to home for those working to protect the waters of Flathead Lake and its surrounding network of rivers and creeks, and it comes to rest at the doorstep of the Columbia River Basin — the only major watershed in the West still believed to be free of quagga and zebra mussels.

Scientists and conservation groups have issued a clarion call for aggressive steps to stem the infestation’s spread, while the University of Montana’s Flathead Lake Biological Station at Yellow Bay launched a sophisticated water-sampling campaign to test for mussel DNA in Flathead Lake.

“If we in the Flathead Basin are not yet infested, this is likely our last opportunity to put in place, in time for the next boating season, the strongest practical safeguards to ensure we remain free of these enormously destructive invasive species, which could devastate our resources and our economy,” stated a Nov. 22 letter to Gov. Steve Bullock, authored by leaders of the Confederated Salish and Kootenai Tribes, the Blackfeet Nation and the Flathead Basin Commission, a group tasked with protecting aquatic resources, who urged immediate executive action.

»»» What are mussels? How do they spread? What do they threaten?

On Nov. 30, Bullock announced a statewide natural resource emergency for Montana water bodies, and a day later, state agencies imposed restrictions on the two reservoirs where the species have turned up (positive detections have since been made on the Milk River near Malta, downriver from Nelson Reservoir, and the Missouri River near York).

Although the executive order drew universal praise from stakeholders in the Missouri and Columbia basins, and frees up financial resources to address the threat, many observers were dismayed that the state waited as long as it did to act.

According to Greg Lemon, information bureau chief for Montana Fish, Wildlife and Parks, the state was notified Oct. 17 by the U.S. Bureau of Reclamation that a “suspect sample” had been discovered in Tiber Reservoir near Shelby. The state prioritized its water samples from Tiber while gathering additional samples, and subsequent lab results confirmed the positive detection of larvae of an unidentified invasive mussel species, either a quagga or zebra. Additional testing later identified positive detections in Canyon Ferry.

As water temperatures drop into the 50s, Lemon said the risk of mussel larvae persisting in the water column is greatly reduced, which influenced the state’s decision to explore other risk-mitigation strategies before enforcing restrictions. FWP also formed an interagency task force to contain the mussel introduction, while deploying divers and mussel-sniffing dogs to search for adult mussels in the contaminated waters.

“I think hindsight might provide some clarity, but we didn’t know then what we know now,” Lemon said. “We are coming into a season where the possibility of transmission is very, very low because of the water temperatures.”

Caryn Miske, executive director of the Flathead Basin Commission, was critical of the lag time between detection in the water samples and action by the state, noting that Glacier National Park and the Blackfeet Indian Reservation responded immediately by closing all waters to boat traffic until the risk was better understood.

“The prudent thing to do when the state found out would have been to funnel all boat traffic in and out of Tiber and Canyon Ferry reservoirs and require full decontamination,” Miske said. “Instead they let boats traipse around the state to God knows where, fouling who knows how many other water bodies.”

Researchers at the Flathead Lake Biological Station also took swift action, deploying the station’s 30-foot Jessie-B research vessel and a team of scientists, who plied the frigid water of Flathead Lake with a renewed sense of urgency, employing tow nets to scan for an aquatic adversary they’d long hoped to keep at bay.

Phil Matson, research specialist with the Flathead Lake Biological Station, collects an eDNA sample along the north shore of Flathead Lake on Dec. 2, 2016. Greg Lindstrom | Flathead Beacon
Phil Matson, research specialist with the Flathead Lake Biological Station, collects an eDNA sample along the north shore of Flathead Lake on Dec. 2, 2016. Greg Lindstrom | Flathead Beacon

Samples from more than 30 sites across Flathead Lake are now being tested by Bio Station Research Professor Gordon Luikart, a world leader in emerging eDNA (or environmental DNA) techniques, a revolutionary technology that can detect the presence of targeted invasive species more quickly and efficiently than conventional measures.

“At the Bio Station, we didn’t have to worry about what the state was or was not doing, and while we are glad that Gov. Bullock declared a state of emergency, we began sampling immediately, before that was announced,” Shawn Devlin, assistant research professor at the station, said. “The fact that they are a three-hour drive from Flathead Lake is very alarming, and even though we are cautiously optimistic, it does not bode well.”

Aquatic invasive species are not new to Montana waters, but the most damaging to aquatic ecosystems, such as quagga and zebra mussels, have not yet been found in the state until now.

Zebra mussels were first discovered in this country in the Great Lakes in the 1980s. The first documented infestation west of the Rockies came in 2007, in Lake Mead in Nevada, with quagga mussels.

Both zebra and quagga mussels are filter-feeders, and can decimate a fishery’s food web, affecting entire populations of fish.

“Essentially, what zebra and quagga mussels do for a living is eat phytoplankton; they filter it out of the water column, which leaves little food for the zooplankton,” Devlin said. “If there is no zooplankton, there is no food for other fish to grow, so all the nutrients and energy that was going into phytoplankton and zooplankton and bigger fish now goes into the mussels. It completely clears the lakes, and turns the trophic cascade into a dead end.”

Although they’ve never taken root here, invasive mussels have arrived for years at check stations, carried by unassuming boaters hailing from infested waterways, a lesson in vigilance that underscores the need to bolster the state’s perimeter-defense strategy.

State House Rep. Jim Keane, D-Butte, who served on a subcommittee that crafted legislation leading to FWP’s Aquatic Invasive Species Watercraft Inspection Program, said he’s horrified that mussels slipped through the cracks and hopes the infestation can be corralled before it spreads.

“I am so scared now that it’s arrived. This is our worst nightmare, frankly,” Keane said. “It’s a sad day, and I don’t think the public has a clue about what’s coming. This is going to be absolutely catastrophic to the economy and the environment.”

Jim Elser, the new director of the Flathead Lake Biological Station, calls the discovery of mussels in the Missouri a “wake-up call,” and said he’s optimistic that the emerging eDNA technology will help protect these waters by providing early detection and monitoring without having to spot invaders visually.

“This is serious, but I don’t think we should have such a grim picture,” Elser said. “It’s a wake-up call, but there are lots of examples of lakes surrounded by invasive species that have warded them off. All of the information we have suggests that Flathead Lake is mussel free. We can keep it that way, but we have to step up our efforts.”

Cody Youngbull, a recently hired research professor at the Bio Station, is on the cusp of manufacturing environmental sensors that he invented to provide real-time DNA detection of invasive species such as quagga or zebra mussels using eDNA technology pioneered by Luikart.

Its application as an early-warning detection system is unprecedented. In a sprawling body of water like Flathead Lake, relying on visual assessments to search for invasive mussels is like looking for a needle in a haystack.

With Youngbull’s technology — called Digital Droplet PCR — all it takes is one biological cell.

“The response time, the lag in understanding, the whole wait-and-see approach would be dramatically reduced, and it would be more effective,” Youngbull said. “Instead of waiting weeks, we would know the results in real time.”

Phil Matson, research specialist with the Flathead Lake Biological Station, collects an eDNA sample along the north shore of Flathead Lake on Dec. 2, 2016. Greg Lindstrom | Flathead Beacon
Phil Matson, research specialist with the Flathead Lake Biological Station, collects an eDNA sample along the north shore of Flathead Lake on Dec. 2, 2016. Greg Lindstrom | Flathead Beacon

According to FWP, the state spent nearly $1 million on AIS prevention efforts in 2015, helping to fund educational and outreach campaigns, such as its “Clean. Drain. Dry.” program, as well as manning the state’s 22 mandatory boat-inspection stations during boating season. Last year, the check stations conducted 37,000 inspections and turned up five boats contaminated with zebra or quagga mussels.

According to Miske, the state’s prevention efforts are inadequate, and pointed to the Blackfeet Nation as a model for aggressive action.

“In 2015, the Tribe passed the most robust AIS prevention statute in Montana,” she said. “It requires the inspection of all watercraft, motorized and non-motorized, prior to launch in Blackfeet waters. The Tribe’s program is a model of what can be accomplished with political will.”

Miske’s Flathead Basin Commission is working to develop an Aquatic Invasive Species Rapid Response Plan for the region, with hopes of completing a draft by year’s end.

Montana doesn’t have its own rapid response plan, but rather is a partner in a regional Columbia River Basin plan, which Miske said isn’t tailored to the state’s specific needs.

“Since the state doesn’t seem to be moving toward drafting its own rapid response plan, we are writing our own,” Miske said. “The notion that there has been a rapid response is incredible. There was no rapid response.”

Robert Wiltshire is executive director of the Invasive Species Action Network, a Livingston-based nonprofit that specializes in coordinating training exercises designed to prepare state agencies for emergency scenarios like the one playing out in Montana. He’s currently writing an Aquatic Invasive Species Management Plan for Nevada, and has been contacted in the past by state agencies in Montana to craft one here.

“We facilitate and conduct rapid response exercises where we bring people together, lock them in a room and give them a scenario that a mussel has been found,” Wiltshire said. “We run through the exercises, bring dive teams in, put out sample press releases. We work through everything.”

In Montana, an Aquatic Nuisance Species Management Plan was completed in 2002, but it hasn’t developed the framework for a rapid response.

Still, agencies including the FWP, Department of Natural Resources and Conservation, Bureau of Reclamation, and Army Corps of Engineers appear to be working together, Wiltshire said, and have a command structure in place to deal with the issue in the future.

“I do believe that what they have laid out puts them on the right track,” he said. “I really feel like they are taking all the steps right now that need to be taken. If this serves as a wake-up call, that is the positive thing. Why it took them so long to respond, I don’t know.”