Brumbies will be shot from the air in NSW for the first time in years after failed attempts to cull their growing population in Kosciuszko National Park.
Environment Minister Penny Sharpe said the change in approach was essential to protect the park's threatened native wildlife and ecosystems.
"I know this decision will upset some members of the community," she said on Friday.
"I empathise with those who feel distressed that we must undertake control programs."
Environmental groups have long called for the use of aerial shooting, a move that was also supported at a federal parliamentary inquiry in early October.
That inquiry found brumbies posed an immediate extinction risk to native species in the Australian Alps.
Feral horse numbers have exploded since then-NSW Nationals leader John Barilaro opposed culls in favour of trapping and rehoming in 2018.
Some forms of culling were reintroduced in 2021 in an effort to bring the population to a "sustainable" headcount of 3000 within six years.
But numbers have instead been increasing, reaching 18,800 in NSW and 25,000 across the Alps, according to official figures.
Animal rights groups have raised concerns about the accuracy of aerial shooting and claims that it can be conducted humanely.
NSW had put the aerial shooting proposal to public consultation, gaining 82 per cent support from 11,000 submissions.
But Ms Sharpe said it was not an easy decision.
"No one wants to have to kill wild horses," she said.
"Aerial shooting, when carried out by highly trained personnel in accordance with rigorous standards, delivers the best possible animal welfare outcomes."
The Invasive Species Council described the change as a "huge win" for native wildlife and mountain streams.
"Now our park rangers can finally get on with the difficult task of removing thousands of feral horses before our mountains and rivers are trampled beyond repair," advocacy manager Jack Gough said in a statement.
Australian Associated Press
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