Indigenous rangers are key to a radical plan to stop cane toads wiping out native species in the Kimberley — one of the last biodiversity strongholds in tropical Australia.
Traditional owners recently gathered at Fitzroy Crossing to be briefed on the strategy, which would ironically involve the release of small cane toads ahead of the large toads at the invasion frontline.
Macquarie University’s Dr Georgia Ward-Fear said by releasing very small cane toads, called metamorphs, predators got sick but did not die and steered clear of the big toads when they arrived.
“The science says that all of our native predators impacted by cane toads can learn to avoid cane toads if they have a small dose of toxin first,” she said.
“Metamorphs are released in areas with the highest conservation value and that’s where Indigenous rangers are key.
“They are our ‘consultants for country’, identifying areas of high biodiversity, providing ecological understanding of local areas and helping to run the works on the ground.”
Cane toads have travelled about halfway across the Kimberley and have been predicted to reach Broome in two to five years.
Parks and Wildlife Service cane toad education officer Dian Fogarty said since being introduced to Queensland in the mid 1930’s cane toads have changed.
“They have evolved longer legs, they’re bigger, stronger, faster and they’re continually heading west,” she said.
“Goannas, snakes, fresh water crocodiles, northern blue tongue lizards, and northern quolls have been severely impacted.
“When attacked, cane toads excrete a poison. The dose from the large toads at the invasion front can kill rapidly. Some predators die before even before swallowing a toad.”
Cane toads cling to water holes during dry periods then move when the monsoons arrive and can travel 50km in a year depending on the wet season.
They have been seen in low numbers around Fitzroy Crossing for two years and have reached the Mitchell Plateau in the Kimberley’s north.
Balanggarra Ranger James “Birdy” Gallagher, who is based at Wyndham in the Kimberley’s north-east, witnessed the devastation after toads arrived in Balanggarra country.
“There were dead goannas everywhere. One creek we walked up we found 20 dead goannas. It’s really shocking, a bit disheartening and a bit sad,” he said.
The workshop was organised by Macquarie University and the Parks and Wildlife Service Western Australia and funded by the department.