To Protect Bighorn Sheep, Authorities Kill 58 Mountain Goats in Grand Teton National Park

The cull is part of an effort to safeguard the park’s vulnerable sheep herd from the non-native species

An image of a mountain goat sitting in the grass. The coat has a lush white coat.
Mountain goats carry bacterial diseases that are lethal to bighorn sheep and also compete for food. U.S. Fish and Wildlife Service via Wikimedia Commons under Public Domain

Last week, the National Park Service (NPS), in its continued efforts to conserve the native herd of Rocky Mountain bighorn sheep in Grand Teton National Park, culled a total of 58 invasive mountain goats in an aerial gunning operation, reports Kris Millgate for Field and Stream. According to the NPS, the removal method, which employed contractors in helicopters, is safer and more effective than the park’s previous ground-based hunts that enlisted trained volunteers, a statement from the agency explains.

The conservation effort is part of the park’s Mountain Goat Management Plan, launched in 2020 to protect bighorn sheep from habitat competition and bacterial diseases that the goats carry. As outlined by the original plan, the NPS enlisted “qualified volunteers” to aid the park in culling the goats, an earlier statement explained. In 2020, 108 volunteers killed 43 non-native mountain goats. Volunteers were invited again for another round of hunting in the fall of 2021, when 20 mountain goats were killed, per a NPS statement.

Now in its third year, the program pivoted to using aerial sharpshooters after the safety of volunteers was brought into question. The recent NPS statement explains that a team of volunteers attempting to recover culled mountain goats this past fall was left stranded overnight and needed assistance to descend from the area the following day. With fewer mountain goats left after several culling events, the NPS decided that the aerial method was the more prudent approach.

Last week’s cull was the second time Grand Teton used aerial operations to reduce mountain goat numbers. The NPS hired contracted helicopter gunners in February 2020, when 36 were removed, reports Billy Arnold for the Jackson Hole Daily.

Bighorn sheep used to roam by the millions across North America, but, by the early 1900s, numbers dipped to the thousands. Sheep died due to hunting activities and diseases brought by domestic sheep, reported Jerry Painter for the Post Register in 2019. Pushed to areas of the West, like the the Teton Mountain Range where they have roamed for millennia, bighorn sheep populations today are smaller and at risk for extinction. The NPS estimates that the current Teton Range herd has only 125 individuals.

Mountain goats present a massive problem for the native sheep. The ungulates carry bacterial diseases that are lethal to the traditionally isolated herd, per the NPS statement. First introduced in the Snake River Range along the Idaho-Wyoming border for the purpose of hunting, mountain goats eventually migrated and established themselves in the Teton Range in the 1960s and 1970s, per the Post Register. The goats also put pressure on already limited food sources for the sheep.

“Where we think that issue really becomes significant is on winter ranges,” Doug McWhirter, a wildlife management coordinator at the Wyoming Game and Fish department, told the Post Register. “In the Tetons, those winter ranges are very restricted, high elevation, wind-blown areas, and they don’t support a lot of mouths.”

More than 100 goats have been culled since the management plan began, but there could be more. “Given the terrain, it is hard to determine precisely how many mountain goats remain in the park,” Jeremy Barnum, the Grand Teton National Park chief of staff, recently told the Jackson Hole Daily. “Every mountain goat that was located was removed, but we assume there could be a few remaining in the range.”