Traditional owners on Australia's largest sand island say biosecurity checks are needed to stop the spread of one the world's worst invasive ant species near the World Heritage-listed area. Five colonies of yellow crazy ants have been found in the Queensland town of Maryborough, which is one of the gateways to K'gari (Fraser island). The detection follows the spread of yellow crazy ant colonies in the Hervey Bay suburb of Booral, which is near the airport and the departure point of a barge used by thousands of tourists to access K'gari every year. The 500,000 annual visitors to the island are not subject to routine checks and vehicles belonging to residents, tourists and four-wheel drive enthusiasts could transport yellow crazy ants or other invasive species to the island. Natural Integrity Alliance for K'gari chair Sue Sargent said the spread of the ants in the region meant it was inevitable they would gain a foothold on K'gari if biosecurity was not improved. "My first reaction is fear," she said. "It's extremely concerning. "It would be devastating for K'gari to get this species." Butchulla Aboriginal Corporation director Conway Burns said the lack of vehicle checks meant traditional owners did not know what to expect from visitors. "We could have some kind of biosecurity set-up where we can have wash down bays where we can wash them down before they go on," he said. "It's important that we put these in place." Millions for ant eradication Yellow crazy ants are believed to have originated in South-East Asia and likely arrived in Australia on cargo ships. The acid-spraying ants can form "super colonies" containing hundreds of queens and millions of ants, because they do not display aggression against one another. Their numbers exploded in the 1990s and the Queensland and federal governments committed significant resources to a successful eradication campaign in the World Heritage-listed Wet Tropics. The Wet Tropics Management Authority receives $6 million in funding per year, but the federal government has not committed to maintaining it beyond mid-2026. Queensland Primary Industries Minister Tony Perrett said the responsibility of managing yellow crazy ants outside the Wet Tropics was the responsibility of local governments. A Fraser Coast Regional Council spokesperson said the ant colonies in Maryborough had been treated but complete eradication was "unlikely at this stage". The spokesperson said the council had "a long-term strategy aimed at eventual eradication" of yellow crazy ants in the region but did not receive any state or federal funding to support that effort. Reece Pianta from the Invasive Species Council said K'gari was no less important than the Wet Tropics and deserved the same level of funding and attention. "I am concerned that they might not have the resources to deal with this threat," he said. Traditional owners develop strategy The Butchulla Aboriginal Corporation (BAC) has received a $390,000 federal grant to develop a biosecurity strategy for the island. A key aspect of the strategy is the implementation of biosecurity checks of vehicles accessing the island. BAC director Christine Royan said further funding was needed to ensure the strategy could be implemented before the Brisbane Olympics in 2032. Queensland Environment Minister Andrew Powell said news of the species' spread on the Fraser Coast was "devastating". He said his department was working with the Department of Primary Industries to contain the outbreak as quickly as possible.