Scientists on the hunt for an endangered native marsupial in the Gold Coast hinterland are worried for the future of the species after last year's bushfires.
QUT senior lecturer and mammologist Andrew Baker said he would expect up to 20 captures of the endangered black-tailed dusky antechinus during their winter field trips, but so far they have trapped none.
"The preliminary survey results in June-August this year show further evidence of a marked decline in not just the antechinuses, but all small mammals," Dr Baker said.
Springbrook National Park was spared the 2019 bushfires that destroyed the historic Binna Burra Lodge in neighbouring Lamington National Park.
"The forests were primed to burn and the populations were pretty heavily impacted even before the fires started, because of drought," Dr Baker said.
He said they found the first recent evidence of the black-tailed dusky antechinus on an escarpment near Binna Burra last year.
"When you get right out to the edge, where the altitude's higher, the dogs detected them out there," he said.
We're keen to go back to Binna Burra and do a bit more of a search.
"We're nervous about what we'll find."
Surveys for the endangered antechinus will be expanded beyond Springbrook to Lamington National Park, Main Range, Mt Barney, and into northern NSW as part of the Federal Government's $200 million Wildlife and Habitat Bushfire Recovery Program.
"All our data suggests that the black-tailed dusky antechinuses have retracted to the highest and wettest areas in the Scenic Rim and now may have nowhere left to run," Dr Baker said.
An evolutionary dead-end
If you were going to design a breeding system that ensured your species' survival you would not copy the marathon mating rituals of antechinuses.
"Mating can last anywhere from 20 minutes to 10 hours or more at a stretch — non stop," Dr Baker said.
"At the end of the breeding season all of the males basically drop dead from exhaustion [and] a deadly chemical cocktail that's surging through their system."
Dr Baker said it was triggered by testosterone which built until it blocked the cut-off switch to the stress hormone cortisol, which eventually poisoned them.
"The antechinus have been driven into this evolutionary corner over time through the females selecting for larger and larger males [with more testosterone]," he said.
There is hope for the black-tailed dusky antechinus with highly-trained dogs tracking their scent on two recent field trips in Springbrook National Park.
"They're still detecting at a few spots up there so we're assuming that means the animal is still there," Dr Baker said.
The surveys can only occur in winter, prior to the September mating season, and further field trips are planned for 2021.
