Cane toads have been wreaking havoc on native species since they were introduced to Queensland almost a century ago, but now they could have a job saving endangered turtles from goanna attacks.

Key points: A study for the next two months will observe whether dead cane toads placed on turtle nests deter goannas

A study for the next two months will observe whether dead cane toads placed on turtle nests deter goannas Goannas pose an increasing threat to the endangered loggerhead turtle as they dig up the nests and take the eggs

Goannas pose an increasing threat to the endangered loggerhead turtle as they dig up the nests and take the eggs Toads for the trial are being supplied from 'toad buster' programs and donations via social media

At Wreck Rock, near Agnes Water, turtle rescue volunteers noticed that goannas were getting into the loggerhead turtle's nests and taking the eggs.

After witnessing goannas avoiding cane toads on the beach, they hatched a plan.

Together with researchers from University of Queensland, Turtle Care volunteers are placing dead toads on top of the turtle nests.

The study, two years in the making, will examine whether the toads will prevent goannas from eating turtle eggs.

"It could be a real purpose for the cane toad; we might be able to do something with it, and it might become a hero," volunteer Nev McLauchlan said.

The loggerhead nests will feature several types of dead toads as part of the research. ( ABC Wide Bay: Johanna Marie )

Researcher Paige Rahn explained that the 'trap' would be set by tying a dead toad to a piece of string, attaching it to a post about 50 centimetres from the nest and then it would be placed on the nest.

She said they will observe whether any of the hatchlings are affected by having cane toads on their nests.

"When the hatchlings come up, we're going to collect 10 hatchlings and weigh them, measure them, count their scales, to see if there's any difference," Ms Rahn said.

Mr McLauchlan said they would also watch the goannas' behaviour.

"One group of nests will have freshly-killed toads, the other group will have toads that have been killed and frozen, and the other will be controlled nests with no toads on them."

The toads will be replaced every week until the hatching season starts in two months.

Fox predation down, goannas up

Goanna numbers in Deepwater National Park have swelled and volunteers believed it was a direct result of the eradication of another predator — foxes.

Foxes used to destroy more than 90 per cent of eggs, but that has dropped to just 5 per cent since the Queensland Department of Environment began their eradication program.

Goannas have become a big problem for nesting loggerhead turtles in recent years. ( Supplied: University of Queensland )

"We've got a big problem with goannas now digging up the turtle nests and it's becoming more important to stop this," Mr McLauchlan said.

"You've got to be here with each nest every day to make sure the nest isn't disturbed and monitor the goannas.

"Being a native animal it's very hard to deter them without hurting them."

Shopping for toads

Fellow volunteer Bev McLauchlan said the hardest part was sourcing enough toads, even though an environmental group in Agnes Water supplied frozen cane toads through its 'toad buster' program.

"I actually rang my brother who lives at Cooroy and he's got a farm, I said, 'Can you collect us some?'," she said.

"A few of the locals have put out a call for assistance on Facebook, and we've collected about seven here in the national park."

The dead cane toads will be replaced every week for two months. ( ABC Wide Bay: Kallee Buchanan )

Cane toad spray?

The trial started last week and will run for two months.

If successful, researchers could develop a cane toad spray to use on nests.

"We're really hoping something from the cane toad is deterring goannas," Mr McLauchlan said.

"If that's the case we want to put that evidence to various people so that maybe we can get a product made.

"The next stage will be to find what part of the cane toad will deter the goanna, and extract whatever that product is.

"We've also got to determine that that's not going to harm the nest or the hatchlings as they come up through the sand, or other wildlife that may be on the beach as well."