Flathead Lake State Park Manager Amy Grout says for some mysterious reason, everything on Wild Horse Island happens a bit ahead of schedule.

Baby bighorn sheep are usually born a few weeks earlier than expected, flowers on the island bloom sooner than those along the shores of Flathead Lake, and seasonal birds can be spotted floating around the property a few days before their season technically starts.

“It’s strange,” Grout said.

But there is another, newer island inhabitant that shows up early to the party as well, and is one park officials describe as uninvited and unwanted. Specifically, Grout has coined it her “biggest challenge” when it comes to managing the habitat on Wild Horse Island.

She’s talking about cheatgrass — an invasive plant species that has emerged in groves in recent years across the island and is threatening populations of native plants that

“The problem with cheat grass is that it’s nonnative to the community so it out-competes other native plants. Cheatgrass is called ‘cheatgrass’ is because it germinates in the fall, it gets a running start,” Grout said. “So when spring comes it steals nutrients from the other plants that our wildlife is depending on.”

Animals on the island don’t eat the cheatgrass and are therefore not naturally managing the populations, she noted. Up until recently, Grout was unsure of what to do about the vegetation, but the Wild Cheatgrass Foundation and the Wild Sheep Foundation partnered with state parks to help fund a research project.

A team recently established testing plots where they are “applying macro and micro nutrients to the soil at different levels to prevent growth of cheatgrass,” and will study those plots in the coming years to see what ratio might best fend off the vegetation. So far, she said the results look promising.

“Initial evaluations suggest that this could be a solution for us,” Grout said.

Grout is quick to credit the state park’s many partners for launching the eradication research efforts, as well as their assistance with other projects on the island. She said finding solutions to problems such as these often require bringing in outside specialists that come with steep price tags and can strain the already-tight budget for the island.

The annual maintenance budget for the island, according to executive director of the Montana State Parks Foundation, Coby Gierke, sits between $10,000 and $15,000, depending. Grout said some years that number has been closer to $5,000.

“There isn’t a lot of wiggle room, so finding partners who understand and want to invest in the value of this island is crucial,” Gierke said.

The cheatgrass project is one of several currently underway on Wild Horse Island to ensure the 2,160-acre wildlife refuge remains hospitable for the island’s famed wild horses, bighorn sheep and mule deer.

In addition to treating cheatgrass, young volunteers with the Montana Conservation Corps are transforming a “social trail,” into an actual designated switchback hiking trail. The current path, created by countless cross-country island hikers over the years, shoots straight up a prominent hillside on the island, that — to the credit of those who have gone off-trail — offers exceptional views of Flathead Lake and surrounding lands from the top.

But the trail has led to unnecessary and aggressive downhill erosion that is impacting surrounding vegetation life. The switchbacks will help remedy rain runoff, among other things. According to Rosalie Ramirez, one of the corps volunteers, the project involves remediating old trail and creating new switchbacks to the top. Ramirez said it’s “an honor” to help maintain the island’s habitat.

Volunteers, as well as organization partners, are two ways in which park officials are able to stretch their budgets. For this upcoming fall and spring, these projects and others, including replacing island signage that has been gnawed away by horses and the removal of specific pine tree clusters, is estimated to cost more than $20,000.

To help fund the undertakings, the Montana State Parks Foundation recently launched the Flathead Lake Action Fund.

“This fund was created for visionary projects and will also raise money for emergent projects like these that aren’t necessarily in our immediate budget,” Gierke said.

The fund holds almost $120,000 to date. A large portion of that came from the Wild Sheep Foundation earlier this year after the organization sold 10 replica skulls made to scale to the world’s largest bighorn sheep — a mammoth animal that died of natural causes on the island in 2016. The foundation gifted about one-third of the proceeds, or about $37,000, to the Flathead Lake Action Fund.

“To be able to take something as unique and interesting as a world record bighorn sheep and come up with a strategy to benefit all parties, was pretty great work,” Gierke said.

Other contributors to the fund include Montana Fish, Wildlife and Parks, the Mule Deer Foundation, which has recognized Wild Horse as a thriving refuge for the animals, and the Montana Recreation Trails Program, which has taken note of the island’s increasing visitation numbers over the years.

“This is a primitive park. The animals really are the draw for people,” Grout said.

As the name would suggest, the island is home to five horses of Spanish Barlo decent that were brought over from Great Falls in 2010. But the island is also home to an estimated 100 to 150 bighorn sheep, about 50 mule deer and one mountain lion. The latter was an unexpected add-on that Grout estimates came over one winter when a large portion of the lake froze over, creating a makeshift land bridge to the property.

Wild Horse is also the largest island on a freshwater lake west of Minnesota — a state park trophy officials hope to own and maintain for years to come.

“We really just want people to continue to see this important island as a really vital part of the Flathead State Parks system,” Gierke said.

Reporter Kianna Gardner can be reached at 758-4407 or kgardner@dailyinterlake.com