An endangered marsupial found only in certain parts of Queensland has been placed on the Federal Government's endangered list partly by having too much sex, researchers say.

The tiny antechinus argentus inhabits the highest peaks of Kroombit Tops, south west of Gladstone in central Queensland, as well as two isolated areas near the Queensland–New South Wales border.

The Queensland University of Technology's Andrew Baker said the males have so much sex during mating season that their bodies produce fatal levels of testosterone.

"At the same time every year, they have three-week sex marathon sessions," Dr Baker said.

"It's really just a big session of all the males and all the females trying to mate with each other as quickly as possible and at the end of that … the males all die.

"They all drop dead."

Dr Baker said, by the time the babies were born, there was not one male left alive, which pushes the species into a corner.

"That basically harms the adult population Australia-wide," he said.

"It's basically competition [for] the biggest males and the strongest sperm.

"That competitive process over time has resulted in this scenario where the males will all vanish, annually."

Dr Andrew Baker holds a female antechinus during a recent research trip in central Queensland. ( Supplied: Dr Andrew Baker )

The sex sessions can last from several hours up to 14 hours at a time.

Dr Baker said the exhaustive process also took a toll on the females, but it was the high testosterone levels in the males that ultimately caused death.

"It builds up to such a high level in the males that it blocks the switch that turns off the stress hormone," he said.

"Then they just get these floods of cortisol and it pretty much causes immune system failure that results in internal bleeding and the males just stumble around still trying to find females in that state and eventually just drop dead."

Detection dogs part of the solution

The antechinus argentus, also known as the silver-headed antechinus, was last week listed as 'endangered' on the Australian Government's threatened species list.

Its penchant for sex was not the only threat to the tiny animal.

"They seem to like wet, open forest and there are lots of cattle and horses and pigs in lots of our national parks and unfortunately those invasive species trample habitat that the antechinus might use for nesting or foraging," Dr Baker said.

"And then we've got the climate change issue because the animal is already at the highest altitude where they're found, so they've got nowhere left to go, really."

Thousands of metal box traps have been set throughout the mammals' habitat areas over the last five years to allow the researchers to study the animal further.

Dr Baker said the research group had also been working with a group called Canines for Wildlife that trained detection dogs to sniff out the rare species in areas where they were not normally found.

"We were wondering if they were in more places than we currently realised," he said.

"In the middle of last year, we had some success and found one of the rare antechinus in a place that it hadn't been seen since the late 1980s and the dog found that on the first or second day of deployment.

"The dogs are geniuses; it is quite astonishing."

The research group will now broaden its detection dog program to try to help the species regenerate to a level where it can be removed from the endangered species list.

Dr Baker said it would not be easy.

"We're lucky that a couple of places where they occur are actually already national parks," he said.

"If we all work hard over the next few years we can save these species, because as we know, the human threats [like] climate change and so on are predicted to get worse."