SYDNEY, Aug 16, 2021 (BSS/AFP) - 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 Monday.
Scientists had feared for the future of a key population of silver-headed
antechinus, only formally identified eight years ago, when wildfires in 2019
swept through much of their habitat in the Bulburin National Park in
Queensland, eastern Australia.
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 Andrew Baker of the Queensland University
of Technology who led the search with PhD candidate Stephane Batista.
With a third of their habitat burned, 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 causes 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," Baker said.
- Threatened by cats, climate change -
Scientists trapped the surviving marsupials from late May to early June
this year, using detection dogs to sniff out the best areas to place traps or
sensor cameras in an operation funded by World Wide Fund for Nature-
Australia.
Baker said the outlook for the silver-headed antechinus was clouded by the
impact of climate change creating more frequent droughts and fires.
In addition, they were threatened by non-native predators such as cats and
the destruction of the undergrowth they live in by animals including cows,
horses and feral pigs.
WWW-Australia's Daniel Grover, who took part in the search, said it was
important to conduct research into the species after the fires.
"The silver-headed antechinus was only described to science in 2013, was
immediately declared endangered, and then hammered by fire. We can't let its
story be 'discovered today, gone tomorrow'," he said.