The former politician and pro-brumby advocate who campaigned for new protections for wild horses in NSW has denied any vested commercial interest in lobbying the NSW Government, calling it a "skilful use of democracy".

Peter Cochran, a former Nationals MP for Monaro and one-time donor to the Nationals who runs horseback brumby tours in Kosciuszko National Park, dismissed the outrage from the scientific community as an environmental "conspiracy".

In June, the NSW parliament passed the Kosciuszko Wild Horse Heritage Bill 2018, seeking to establish a "sustainable wild horse population" inside the National Park, and to recognise their heritage value.

"It's not as close to what we proposed as I would have liked," Mr Cochran told 7.30.

"After 50 years of being involved in politics in this country, I know how to get round the place."

Peter Cochran's Facebook post 20 May 2018 ( Source: Facebook )

Mr Cochran also denied drafting the legislation for the NSW Government, despite admitting the "Bill [sic] was originally drafted under instruction from myself" in a Facebook post on May 20.

However, the NSW opposition said "Cochran's Horse Treks stands to profit from [the] passage of [the] legislation".

After Mr Cochran's political career with the Nationals he established a horse riding business in Kosciuszko National Park, offering tourists the experience of seeing "brumbies in the wild".

He denied he had a vested commercial interest in maintaining a wild horse population, but told 7.30 there was a "tourist element to it".

Calls for the Commonwealth to intervene

There are up to 6,000 wild horses on an estimated 48 per cent of Kosciuszko National Park. ( ABC Open contributor snowy_brumby_heritage )

There are up to 6,000 wild horses on an estimated 48 per cent of Kosciuszko National Park, which are now protected in NSW and culled in the ACT and Victoria.

The NSW move sparked outrage in the scientific community, which had advised the NSW Government that wild horses are a "key threatening process" for endangered native flora and fauna in the National Park.

Few Australians have more international clout in wilderness land management and conservation than Dr Graeme Worboys, who told 7.30 the NSW law could conflict with the Federal National Parks Act.

"On national heritage matters [the Commonwealth Government] have powers. They can intervene. They should intervene," Dr Worboys said.

"All the science, from our various institutions, says that wild horses in national parks are unacceptable."

Dr Worboys said the appointment of a NSW panel of community advisors, with no land management or conservation experience, erodes the authority of park rangers and politicises their attempt to control a feral animal.

"National parks staff can shoot deer, they can shoot pigs, they can deal with foxes and cats but they can't shoot horses," he said.

'We are hoping NSW will return' to collaboration

The Mountain Pygmy Possum is just one endangered species whose habitat is being damaged by brumbies. ( ABC News: Lucy Barbour )

The NSW decision on land management has also caused disquiet in Victoria, which culls wild horses.

Horses can freely cross the states' shared border if not properly managed.

"Victoria and NSW have got a really strong collaborative history of working together to reduce the pressures on our alpine environments," Dr Mark Norman of Parks Victoria said.

"We're hoping that NSW will return to these sorts of collaborations on seriously reducing the impact on these special places."