WILD HORSE ISLAND — Even the most well-thought out plans can go awry. Only nine months after Montana Fish, Wildlife and Parks officials added a set of four wild mares to fill the management plan quota for Flathead Lake’s Wild Horse Island, in an unexpected twist, a sprightly painted foal has now joined the herd.

FWP officials noticed the young filly a few weeks ago, and according to Flathead Lake Parks Manager Jerry Sawyer, she is now around five weeks old.

“We didn’t realize that one of the mares was pregnant, so it was a surprise to us as well,” Sawyer said. “She seemed healthy and was getting around pretty well.”

Even though the management plan only calls for five wild horses to roam the 2,164-acre site, there are currently six adult horses on the island, including an older gelding park officials thought would not make it through the winter.

“He’s looking pretty rough, although he did survive,” Sawyer said. “When he goes, there will be five mares and one gelding.”

While that means the herd is going to be larger than intended, it’s not out of the range of acceptable numbers, so Sawyer said there are no plans to relocate the filly.

“We’re going to just leave it out there,” Sawyer said. “It has some historical significance because it’s the first wild horse that has been born on the island in probably 100 years.”

State Senator Brad Hamlett and Lyle Heavy Runner of Great Falls donated four wild mares, including the mother, to Montana Fish, Wildlife and Parks last June.

The largest island on Flathead Lake, Wild Horse has been a landmark rich with history since members of the Salish tribe used the island in the 1800s as a safe haven for their equine during battles with other tribes. Wild Horse Island became a state park in 1978, and although the island’s original band of wild horses is long gone, its namesake tradition was kept alive through the Bureau of Land Management’s “Adopt a Horse” program.

While not often home to predatory species, there is competition for forage with the island’s other inhabitants, mainly the large herds of big-horn sheep and mule deer.

“It’s a confined area and resources are limited,” Sawyer said. “We have to find that balance between species and diversity.”

According to Sawyer, roughly 15,500 people typically visit the island from mid-May to mid-September, and this new filly will be an added attraction.

“For a while, it will certainly be a novelty and should generate a lot of interest,” he said. “We have had some problems with people feeding the horses out there and the horses becoming habituated. We want to inform people to please respect the distance, and if they start walking toward you, the best thing to do is just walk away.”