By Jessianne Wright EBS Contributor

BIG SKY – Within a matter of a couple years, tiny mollusks like zebra mussels and Eurasian mud snails can blanket an entire shoreline and drastically alter a water body’s ecosystem.

Zebra mussels have been identified on at least five watercrafts in the state of Montana this year, and Eurasian watermilfoil and New Zealand mud snails have already entered watersheds throughout the state.

Recognizing the threat of aquatic invasive species to the Gallatin River, the Gallatin Invasive Species Alliance, formerly the Gallatin-Big Sky Weed Committee, has reconfirmed its commitment to protect Big Sky from their detrimental effects.

The committee board elected to change the organization’s name so as to better reflect the issue of all invasive terrestrial and aquatic species.

“There’s a lot of [whitewater] boat use on the Gallatin. There’s thousands of fishing days on the river too,” said John Councilman, GISA board chair. “Some very invasive species have already been found in the state. We’ve been familiar with the issue for a long time.”

For the time being, the alliance will continue to focus on invasive nonnative plants, but in the future, they plan to develop programs with the Gallatin River Task Force that target aquatic species as well.

“Any kind of disruption to the soil is a kind of vector for invasive species. [Big Sky] is surrounded by wilderness. It’s surrounded by some very high valued areas,” Councilman said, adding that Big Sky is a critical area to protect due to the soil disruption that occurs during construction or development. “There are so many places in the state that are already overcome with noxious weeds.”

GISA executive director Jennifer Mohler is a wealth of information for identifying and managing nonnative species and she says the alliance, which was originally formed in 2004, is still the local source for any questions pertaining to invasive species in our area.

Mohler is available for onsite consultations and will also have a booth at the Big Sky Farmers Market every Wednesday this summer to provide resources and identify plants. In the past 15 years, she says she’s only visited one property in the area that didn’t have any noxious weeds present.

Beyond providing education about invasive species, the alliance takes an active role in eradicating noxious weeds.

This summer marks the eighth year of a habitat improvement program on the hillside west of Highway 191 and north of Lone Mountain Trail, which serves as important winter range for bighorn sheep.

“Weeds got a foothold during early development,” Mohler said, adding that the plants quickly spread up the hillside and pushed out native plants. “Every winter range is really critical for wildlife, that’s what they survive on. [Noxious weeds] directly impact the amount of available forage.”

Volunteers from the committee have spent the past seven summers treating the noxious weeds, and Mohler said they’ve seen impressive results. They’ve also planted test plots to monitor how and if native plants can successfully return to the ecosystem.

“If we wait, the noxious weed population has an opportunity to get healthier … and at some point, it’s not about elimination, it gets to be a point of just keeping it at bay. Every new development provides an opportunity for spread. I’m seeing the tsunami on the horizon,” she said. “But if we keep this ball rolling, we can keep Big Sky beautiful.”

The Gallatin Invasive Species Alliance will hold volunteer weed pulls on Saturday, June 9, at Portal Creek Flats at 10 a.m., and Tuesday, June 19, at the Big Sky Community Park at 4:30 p.m. There will also be three Wildflower and Weed Walks this summer, where hikers can learn to identify native plants, held June 21 at Deer Creek, July 24 at Ouzel Falls, and Aug. 16 at Beehive Basin. These walks begin at 10 a.m.

To learn more about the Gallatin Invasive Species Alliance, visit gallatinisa.org.