'Suicidal reproducer' marsupial survives Aussie fires

The male silver-headed antechinus dies before it is one year old from the effects of an intense two-week mating season. Females rarely survive to a third breeding season. PHOTO: AGENCE FRANCE-PRESSE
The male silver-headed antechinus dies before it is one year old from the effects of an intense two-week mating season. Females rarely survive to a third breeding season. PHOTO: AGENCE FRANCE-PRESSE

SYDNEY • A rare, shrew-like Australian marsupial, whose males die en masse from stress after a "frenetic" mating season, has survived devastating wildfires that scorched one of their few habitats, researchers said.

Scientists had feared for the future of a key population of silver-headed antechinus, formally identified eight years ago, when wildfires in 2019 swept through much of their habitat in the Bulburin National Park in Queensland.

It is one of only three known habitats in Australia for the species, which survives largely on insects and spiders.

"We found 21 individuals across burnt and unburnt habitat, which is great. It means they are persisting," said Dr Andrew Baker of the Queensland University of Technology who led the search with PhD candidate Stephane Batista.

With a third of their habitat razed, Dr Baker said he had feared finding none of the animals.

The male silver-headed antechinus already lives a precarious life, dying before one year of age from the effects of an intense two-week mating season. Females rarely survive to a third breeding season.

"With the males, high testosterone levels from super-sized testes cause a failure of the switch that turns off the stress hormone cortisol. So they get flooded with cortisol during the breeding season and ultimately it poisons them.

"The males suffer internal bleeding, their hair falls out, sometimes they go blind. Even then, they may stumble around looking for females to mate with until they die," Dr Baker said.

World Wide Fund for Nature-Australia's Mr Daniel Grover, who took part in the search for the marsupials, said it was important to conduct research into the species after the fires.

"The silver-headed antechinus was only described to science in 2013, immediately declared endangered, and then hammered by fire. We can't let its story be 'discovered today, gone tomorrow'," he said.

AGENCE FRANCE-PRESSE

A version of this article appeared in the print edition of The Straits Times on August 17, 2021, with the headline ''Suicidal reproducer' marsupial survives Aussie fires'. Subscribe