Prolonged drought and other effects of climate change are pushing the duck-billed platypus, one of Australia's most unique species, towards extinction, scientists warned in a study published Monday.

The furry river-dwelling mammal has already disappeared from as much as 40 percent of its historical range on the east coast of Australia due to drought, land clearing, pollution and the construction of dams, the researchers said.

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Scientists from the University of New South Wales' Centre for Ecosystem Science say if the current threats persist, platypus numbers will fall a further 47-66 percent over the next 50 years.

If projections about worsening climate change are taken into account, the numbers of the egg-laying mammal could plummet up to 73 percent by 2070, they wrote.

"These dangers further expose the platypus to even worse local extinctions, with no capacity to repopulate areas," said Gilad Bino, lead author of the study.

Experts say as many as one billion animals may have died in the massive bushfires that took hold of Australia's tinder-dry bush in September, tearing through vast swaths of the country's more-populated southeast and destroying crucial animal habitats.

In work published towards the end of last year, Australian scientists found that 100 of Australia's endemic species had gone extinct since Europeans arrived on the continent.

Extinctions to accelerate

The first extinction likely took place within 10 years of colonisation, they said in their findings which were published in the scientific journal Biological Conservation. At least three extinctions took place in the last decade.

A pig-footed bandicoot, one of 100 species that are known to have become extinct since Europeans landed in Australia [Supplied/Al Jazeera]

They found that the introduction of predators like foxes and cats, as well as environmentally significant events like drought and fire, had harmed indigenous species, with climate change emerging as a factor more recently.

John Woinarski of the Threatened Species Recovery Hub at Charles Darwin University's Research Institute for the Environment and Livelihoods and the report's lead author, told Al Jazeera the rate of extinction in Australia was the highest of any continent in the world and "highly likely" to accelerate.

Recalling a species of skink he had once held in his hands and was now extinct, Woinarski said the loss of any species was devastating.

"To have held an animal or plant that has gone extinct in your lifetime, it affects your soul," he told Al Jazeera. "Extinctions are part of us. They aren't remote entities. They are real things that had life and vitality and that has been extinguished."

The platypus is listed as "near threatened" by the International Union for Conservation of Nature and the UNSW scientists said the damage caused by years of minimal rainfall and high temperatures had worsened its prospects.

'Urgent need'

The scientists said there was an "urgent need" for a national risk assessment to determine if the platypus should be recognised as "vulnerable" and to lay out conservation steps "to minimise any risk of extinction".

'It affects your soul' says scientist John Woinarski of species extinctions, recalling the time he held the Christmas Island forest skink (above), which became extinct in the last decade [Hal Cogger/Al Jazeera]

The study is the first across all platypus habitat zones to establish a so-called "metapopulation" model while also projecting the impacts of climate change on the species going forward.

The survey estimated the total platypus population had fallen by 50 percent since European settlement in 1788.

An earlier study published in November 2018 estimated the population had fallen by 30 percent over that period, to around 200,000.

"Under predicted climate change, the losses forecast were far greater because of increases in extreme drought frequencies and duration, such as the current dry spell," Bino said of the latest report.

The platypus, which along with four species of echidna are the only mammals that lay eggs, has a tail like a beaver, otter-like feet and a venomous spur on its hind leg.