Federal Environment Minister Tanya Plibersek wants feral horses removed from Kosciuszko National Park and is backing a new inquiry into their impact and management.
"I love horses but they don't belong in Kosciuszko National Park," she said.
"Feral horses … are damaging fragile alpine and sub-alpine ecosystems and important plant and animal species, such as the iconic corroboree frog."
The inquiry by the Senate's Environment and Communications References Committee was put forward by Independent ACT Senator David Pocock and would report by June 9.
It will investigate best practice for reducing feral horse numbers in the Australian Alps, and their impact on biodiversity, water and Indigenous cultural heritage.
The committee will also look at Commonwealth powers and whether state programs for controlling feral horses are adequate.
The NSW Kosciuszko National Park Wild Horse Heritage Management Plan aims to reduce wild horse numbers from 14,000 in 2020 to 3,000 by 2027.
But its effectiveness has been criticised by environmental groups after new data showed only 859 horses were removed in the first 10 months of operation.
Ms Plibersek said the government wanted to ensure effective management of the site across jurisdictions, and the Alps had been identified as a priority in Labor's threatened species action plan.
"I welcome this inquiry to ensure that we are doing everything we can to effectively manage this precious ecosystem from the impacts of feral animals, such as feral horses," she said.
"The day-to-day responsibility for protection of national heritage places, and the management of invasive species, rests with state and territory governments, but I am providing financial support to the states and territories to reduce the populations of feral horses in the Alps."
Environmentalists welcome scrutiny
The Invasive Species Council (ISC) has described the Senate inquiry as timely and important, given a recent survey that found horse numbers in Kosciuszko National Park had jumped by more than 30 per cent in the past two years.
"We hope that it will shine a spotlight on the impact that these horses are causing but also, importantly, the failures that both the NSW and Victorian governments are having in terms of controlling those numbers quick enough," ISC advocacy manager Jack Gough said.
"The federal government has some really powerful legal options in terms of forcing those state governments to take more extensive action."
The management plan's control methods include passive trapping, aerial and ground mustering, rehoming where possible, and excludes aerial culling.
Mr Gough said the inquiry would push the NSW government to reconsider using aerial shooting.
"We need to have an aerial control trial because we know it's humane and an effective way to reduce populations of feral horses quickly," he said.
"That is going to be difficult without some sort of federal intervention to push this issue along."
A 'political exercise'
Snowy Mountains farmer and brumby advocate Peter Cochran doubted those in favour of horses in the park would be fairly heard.
"It's very much a political exercise … once again people who live within the vicinity of the Kosciuszko National Park will be the losers," he said.
"I don't expect to get any positive results out of it as far as the horses are concerned and I expect the consequence of the report will be that they'll be recommending the complete annihilation of the horses, which falls in line with their political agenda."
The former NSW Nationals MP has been lobbying for the preservation of brumbies for decades, arguing they are a part of Australia's heritage.
"Will the horses be annihilated? Yes, they probably will," Mr Cochran said.
"Will that be of advantage to the people of Australia in the long run? No, it won't, because we'll lose part of our cultural history."
