Heritage-listed K'gari (Fraser Island) is facing a biosecurity threat from pet owners illegally bringing their domestic dogs ashore, authorities say.
The Queensland Parks and Wildlife Service is trying to identify two visitors who moored a yacht off the island mid-October, one of whom took two pet dogs attached to a leash onto the beach.
It's the third report of a domestic animal on the island that rangers have investigated in several months.
Ranger in charge Linda Behrendorff said there were more sightings of someone from a yacht that had brought their dog onto the island to walk it, and then possibly defecate.
"The problem with that is that those animals can either be in danger of being attacked by the dingoes, as well as their owners," she said.
"We don't know whether those animals have been treated for heartworm or other diseases that could be passed onto the [dingo] population."
The truth about cats and dogs
Domestic dogs and cats have been banned from K'gari since 1991.
The ban later expanded to residential areas in 2011 to protect the island's dingo population (wongari), which is among the purest strains in Australia.
Ms Behrendorff said there was dangerous misinformation spreading around the island.
"There is a little misconception there that if you just walk your dogs or take domestic dogs onto the island via the low tide mark, then it's out of the legislation, but that's not true at all," she said.
"Anywhere on that island, including residential areas, we work with the Fraser Coast Regional Council, and domestic animals like cats and dogs are definitely banned."
Fines for the offence range up to $143, but Ms Behrendorff said the consequences were more than financial.
"Unfortunately, it's not overly high, but that's not the point," she said.
"The point is you're dealing with an animal of conservation value in the dingoes on K'gari."
Queensland Parks and Wildlife Service said certified support dogs were permitted in national parks and must wear an identifying coat or harness with an approved tag.
They also must be kept on a leash and owners must have the authorised paperwork.
A timely reminder
Ms Behrendorff said the people who brought dogs ashore from the yacht would be fined once identified.
"It is concerning, I think maybe the education is not getting out there," she said.
"Even if you're on a yacht or whether you're driving on the island there, you do need to be aware of the legislation concerning the area that you're visiting and definitely no bringing domestic animals onto the island, even to defecate or get rid of their waste.
"Just be smart about it, deal with it appropriately."
