Grand Teton National Park to begin killing invasive mountain goats

JACKSON, Wyoming (CBS4) — An operation to kill the mountain goats that have invaded Grand Teton National Park and threaten the existence of the park’s struggling bighorn sheep herd was scheduled to begin Sunday, officials said.

A large swath of the high Tetons, including the north and west slopes of the iconic Cathedral Group, will be closed to the public as aerial gunners contracted by the park spend up to a week locating and shooting at the goats.

“We’re trying to be efficient and effective — so doing this as fast as possible in the most efficient way — and we believe that the aerial operations does that,” park spokeswoman Denise Germann said.

Germann had no prediction about how many animals would be targeted, but said it’s possible that at least one more week of aerial shooting will occur, depending on how the first week of the operation proceeds.

“This will be our initial action, and we’ll see how it goes,” Germann said. “It’s a very unique situation for Grand Teton National Park.”

Park officials have also authorized ground-based hunters to kill goats, but that will not occur this winter, she said.

Flights to locate the goats were supposed to begin Sunday and the shooting, contracted to Oregon-based Baker Aircraft, is set to begin Monday, depending on the weather. Shooters aboard helicopters will use non-lead rounds from a shotgun or rifle, with the weapon type depending on the conditions.

Today’s Grand Teton mountain goat population descended from animals deposited in the 1960s into the Snake River Range from the state of Idaho, and which migrated northeast. Measured seven years ago at approximately 10 to 15 animals, the Teton’s goats are now estimated at more than a hundred head. The habitat has the potential to support as many as 400, officials said.

By contract, the bighorn sheep herd, native to the area, is considered fragile. It also number about 100 individuals, but they have been pushed out of some of their best habitat by backcountry skiing activity, and their existence is threatened by potential disease transmission by the mountain goats.

The supply of winter forage in the park’s high-altitude terrain will not support both herds, NPS biologists previously concluded.

The Grand Teton National Park Foundation called its mountain goats “perhaps the biggest ecological threat to the area in modern history” to the park in 2014.

By 2015, the park service referred to the bighorns’ status as “tenuous.”

Park officials first proposed eradicating the Tetons’ goats in 2013, and plans were finalized late last year.

Eliminating wild goats from the Tetons has received broad public support. But the park’s draft plan released in 2018 was changed to allow for some goats to be relocated if suitable areas were identified.

Another change allowed meat from the killed goats to be salvaged, but recovering any animals shot this coming week is unlikely, Germann said.

“We will retrieve carcasses if we can safely do so, but we believe that may be very challenging,” she said. “If we do recover any carcasses this go-around, they will be used for research purposes.”

The research project, she said, is a collaborative effort with the California Department of Wildlife and University of Utah to look at body condition and nutrition in wild goat herds.

Colorado’s herds, however, do not generally compete for the same mix of territory and thus the same resources, according to a Colorado Parks and Wildlife spokesman.

“Mountain goats mostly stay in their high altitude mountain range year-round,” CPW’s Jason Clay told CBS4, “seldom going below treeline, except in severe winter weather. Bighorns typically occur in steep, high mountain terrain, but are often seen well below timberline.”

Popular locations to see Colorado’s bighorns on the Front Range include Waterton Canyon, Poudre Canyon, Big Thompson Canyon, and St. Vrain Canyon.

Plus, CPW’s Clay said, Colorado’s sheep suffer a greater threat from disease through interaction with domestic livestock than with mountain goats.

Colorado’s mountain goats, like those in Grand Teton NP, are also non-native. Colorado first imported goats from Montana in 1947, then later from Idaho, British Columbia, and the Black Hills of South Dakota.

CPW estimates is bighorn sheep herd at 7,000 animals. Colorado’s mountain goats number approximately 1,500.

The native range of mountain goats lies between states in the northwestern U.S. through Canada and into the southern regions of Alaska.

The Associated Press contributed to this report.