Dianne Thompson has culled a line from the poem to rekindle a decades-long debate about the impact of horses on the sources of the Murray, Snowy and Murrumbidgee rivers in Kosciuszko National Park.

But his hardy mountain pony he could scarcely raise a trot

He was blood from hip to shoulder from the spur

Ms Thompson said people should put aside the romance around the man from Snowy River, who whipped his horse chasing a monetary reward.

''Times have changed," she said. "Feral horse numbers are out of control and real damage is being done."

Rather than relying on the mythology of the poem to protect wild horses, they should be shot, as wild horses are in the ACT’s Namadgi National Park, because of damage they cause to water catchments.

A conservationist and National Parks Association ACT member, Ms Thompson's ancestors were early settlers in Gippsland and her father a drover in Western Australia. Her heritage was as relevant as the one claimed by the horse lobby.

Ms Thompson says passive trapping is ineffective and stresses horses.

“Can you imagine stress for horses, big wild animals that have not had much to do with humans," she said. "If you get them into a yard, they must be separated out, then you have to truck them from the mountain area to goodness knows where.

“Then put them into a yard. People pick them over and they get trucked off again to an abattoir and euthanased.’’

NSW National Parks estimated 7679 wild horses in Kosciuszko in 2009, and counts using internationally recognised surveying put the number at 10,000.

Ms Thompson said 25 years ago she could step across the Ingeegoodbee River at the southern end of the park, but since the damage from feral horses' hooves, it was three to four metres wide.

“The banks have collapsed, the soil lost, the plant life gone, the river straightened, and the run-off is fast, and no longer held by the ancient banks and river valleys,’’ she said.

A wild-horse management plan is being reviewed and widespread consultation will begin soon before a draft release next year.

Snowy Mountains Bush Users Group president Peter Cochran, who rides in the mountains five days a week, says researchers had even claimed 14,000 wild horses at Koscuiszko, which is ridiculous. He did not know the number, but it would not be anywhere near 10,000.

The former member for Monaro refers to wild horses as brumbies and led lobbying to regain access into the southern end of the national park, from Thredbo to the Victorian border.

“The first thing we want is the brumby acknowledged as part of the cultural heritage of the Snowy Mountains. It should be preserved and in a sustainable number,'' Mr Cochran said.

“We don’t have a problem with them culling brumbies using the current technique, trapping. But no aerial shooting, which is barbaric.’’

Bushfires, heavy snowfall and the horses themselves culled herd numbers. National Parks estimates of 20 per cent increases annually were wrong, he added.

“There are old horses they trap that they’ll never break in that go to the knackery, and I don’t have a problem with that,’’ Mr Cochran said.

“Anyone who has transported rogue horses will know some damage will occur when they are moving them. That is going to happen. But it beats the hell out of shooting them, leaving them dragging themselves around the hills for several weeks after being shot from the air. Our optimum is for them to be re-homed.''