A tourist may be responsible for bringing a cane toad into Kosciuszko National Park in southern New South Wales, rangers say.

The dead toad was found beside the road at Charlotte Pass earlier this month, near one of the most popular viewing platforms for Mt. Kosciuszko — much of which is snow-covered in the winter months.

Cane toads are an introduced pest found in Queensland, the Northern Territory and parts of NSW and Western Australia — but are not often found in southern NSW particularly not in alpine environments.

NSW National Parks and Wildlife Officer (NPWS) Dave Woods told ABC Radio Canberra's Adam Shirley it was a scary reminder for people visiting the sensitive environment to be aware of accidently trafficking in pests.

"We don't think it was a joke … but a wayward passenger, from a vehicle that's travelled from either northern NSW or Qld," he said.

"It [the toad] either died in transit or it's fallen out and survived for a few days.

"We strongly suspect given the [area] has high visitation, that it was a tourist that brought it in."

Mr Woods said the animal was found by a ranger and looked like it had been dead for a couple of days.

"We were surprised!" he said.

Chytrid fungus a risk to local frogs

Rangers initially thought the animal could have been an eastern banjo frog — the largest frog normally found in the park at that altitude.

"When it was delivered to the Jindabyne office that afternoon, our identification changed and we said 'we've got a Queenslander'," he said.

Cane toads can carry chytrid fungus which is harmful to native frogs in the area. ( ABC News: Isabella Higgins/file photo )

The area near where the carcass was discovered was inspected by rangers, but there was no evidence of other cane toads found.

However, Mr Wood said the discovery was concerning because although the park environment was generally too cold for a tropical animal like the cane toad, there were drier and warmer areas at lower altitudes, where the animal could survive for several weeks or months.

"There are certainly environment and times of the year when such an animal could persist. That is a logical conclusion," he said.

He said cane toads had the potential to introduce diseases that could pose a risk to other wildlife in the park.

Chytrid fungus carried by the toads, for example, has the potential to wreak havoc among endangered local species of frogs.

For this reason, he said it was important for visitors to be on the look out for pests before they arrived.

"NPWS reminds visitors to check their vehicles for unwanted pest species … before travelling to the park from other areas," he said.