During the trial, authorities slaughtered 270 horses over two days while veterinarians accompanied them in helicopters to observe them, the New South Wales government said.
Authorities said veterinarians also inspected 43 of the horses on the ground and found that “there were no adverse events to the welfare of the animals.”
“The median time from shooting to unresponsiveness was 5 seconds,” the statement said. “No horses were injured non-fatally.”
On average, 7.5 shots were fired to kill each horse, officials added.
After the trial concluded, the government said it was moving ahead with the helicopter shots, adding that it would “not be possible” to meet the 2027 deadline without the program.
Current government estimates for the national park’s wild horse population are between 12,934 and 22,546 horses, with a best estimate of around 17,400.
Why the government wants to reform horses
The horses, called wild horses or brumbies by Australians, are descended from escaped or lost horses brought to the continent by European settlers.
They are often considered a pest which can destroy local environments by compacting and eroding soil, defecating into water sources, and chewing trees.
When their populations become too large, they begin to feed on vegetation, which can disrupt ecosystems and endanger native animal species. Horses can also threaten crops or interfere with agriculture.
The New South Wales government initially attempted to contain the horse population through aerial shooting in 2000, but stopped doing so after facing public outcry.
Supporters of wild horse protection say the animals are part of Australia’s heritage and have denounced the resumption of aerial shooting.
The charity Save the Brumbiesfor example, accused the government of assessing the horse population using “flawed survey methodology” and is urging a recount.
Jan Carter, the association’s founder, wrote a submission to Australian parliament in August, saying the government should focus its efforts on animal repatriation or fertility control.
“Our Heritage Brumbies are a national icon and part of our history,” Carter wrote. “They deserve recognition, not bullets.”
Tensions over horse slaughter have even led to threats against government officials. In September 2022an office at Kosciuszko National Park received a letter saying someone wanted to throw a “firebomb” at the site, police said.