JACKSON — Aggressive efforts to hunt the Teton Range’s nonnative mountain goat population out of existence are having the desired effect: As few as 29 animals remain.

That count of the sure-footed, white-coated animals was the result of a two-day Wyoming Game and Fish Department aerial Teton Range survey that also found 90 native bighorn sheep, the species that’s supposed to benefit from the goat eradication effort.

“I was happy we counted 90 sheep,” Game and Fish Jackson Region wildlife biologist Aly Courtemanch said. “That shows that the herd is hanging on, but I still have concerns about that bighorn sheep population.”

All of the 29 exotic goats Courtemanch found were in Grand Teton National Park, and there were just four kids she was able to tally. The count suggests that the population of the exotic goats is definitely on the downswing, which is expected following two straight years of intensive hunting and volunteer culling both inside and outside of the park. The mid-winter 2020 survey, which was interrupted by weather, found evidence of 56 goats. In 2019, Game and Fish’s survey counted 88 goats.

During 2020, Teton Park used two different tactics to go after its goat population. Deployment of the most efficient method — helicopter gunning — unfolded Feb. 21, 2020, and 36 goats were killed in half a day. That operation, preceded by years of planning, backfired politically and was terminated by then-Interior Secretary David Bernhardt the day it began.

Then last fall, park officials enlisted and trained volunteer hunters to cull the herd. The six-week operation was predictably slower going, but participants still managed to take down 43 additional goats. So altogether, 79 mountain goats — the vast majority of the Tetons’ estimated population — was wiped out during the last calendar year.

Game and Fish has also authorized heavy hunting outside of the park on the Caribou-Targhee National Forest. In 2019, they managed to kill 23, but then the success rate fell off significantly last fall.

“Hunters were having a hard time finding goats,” Courtemanch said. “That’s definitely an indication that the population was down.”

The state biologist was confident her count of 29 remaining mountain goats was a good estimate of what’s left of the Teton population.

“There’s always some that we miss, for sure, but we felt really good about the survey,” she said. “I don’t think we missed a lot of goats.”

There’s lots of snow in the Tetons that bunched the animals up, and she flew on a clear day that followed some fresh snow. Tracks were easy to see.

It’s unclear what lethal strategy will be used to finish off the few dozen remaining animals left.

“At this point, we don’t know,” Teton Park spokeswoman Denise Germann said. “We’re evaluating everything that happened over the last year to determine how to move forward.”

The Tetons’ goats drifted up from a transplanted nonnative herd in the Snake River Range.

Goats are considered a risk to native sheep in the range, both through competition for finite habitat and the risk of disease transmission.

Wyoming Game and Fish has supported the goat eradication, but the agency’s commission and Wyoming Gov. Mark Gordon have both vocally opposed using hired helicopter gunners get the job done. As numbers dwindle, the animals figure to become harder and harder for volunteer hunters to find.

While the raw count of 90 Teton bighorns was OK relative to recent history, Courtemanch’s worries about the small, isolated herd have not abated. There were only 14 lambs she counted in the entire population — a sign of poor reproduction — and some of those youngsters may die before winter’s end.

Southern Teton sheep are also faring especially poorly in a herd that’s effectively broken up into two groups that don’t geographically overlap or breed. The southern segment was down to just 37 total animals with just four lambs, with the northern Tetons housing the remaining 53 animals, including the 10 other lambs.

“Even though there’s 90 sheep, it’s really on the edge still,” Courtemanch said. “It would only take a couple bad winters or a pneumonia outbreak. Any one thing that happens could be catastrophic, because the numbers are so low.”