Later recovering populations probably began to collapse again in inland Queensland and NSW in the 1990s, says Dr Philips, though historical koala data is patchy and contested.

The rapid decline was caused by land-clearing and exacerbated by climate change and disease. It’s well known that koalas cannot live without specific eucalyptus trees, but less well known that, when temperatures exceed 35 degrees, they can no longer cool themselves by embracing their trees.

In this heat, they flee to the ground where they are hit by cars, taken by dogs or simply expire as they begin to metabolise their own muscle for lack of fluids.

Stressed populations succumb faster to diseases such as chlamydia.

“In the past decade there’s been a 90 per cent decline in the Gunnedah koala population, which was once the gold standard,” says Dr Phillips, who believes that population now to number in the hundreds.

In 2017, he visited 150 sites in the Pilliga, another region once host to a healthy population, and found scat at none of them.

“They are pretty well gone now,” he says.

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Research by the Australian Conservation Foundation released on Tuesday found that the federal government had approved 63 projects that would result in the clearing of more than 25,000 hectares of koala habitat since the species was declared vulnerable to extinction 10 years ago

In southern Queensland and NSW, the survivors now cling to the cooler coast on fertile land coveted by farmers, tree-changers and developers. In Victoria, many of the larger populations, free of the diseases more prevalent to the north are descended from captive breeding programs. While healthier in number, these populations are poor in the genetic diversity needed to ensure the species’ survival.

Confronted with this rapid collapse, many observers and campaigners have welcomed Ley’s announcement. Some have noted that she could easily have sat on the decision until after the election rather than act, and that the money she has dedicated to the koala is significant and well targeted.

But listing the animal will not save it. As Dr Philips puts it, unless the few remaining koalas and their fragile remnant habitats are “wrapped in cotton wool”, they will soon become regionally extinct in NSW and Queensland and could be lost entirely.

Greens Senator Sarah Hanson has come to the same conclusion, calling on Friday morning for the federal government to introduce laws for an immediate moratorium on koala habitat destruction.

“That means no more land clearing in koala habitat. No more mines and quarries in koala habitat. That means no more approvals and licences for big property developers to clear and bulldoze in the homes of koalas,” she said.

The cost of such a moratorium would be significant.

But Deborah Tabart, chief executive of the Australian Koala Foundation, who has lobbied for such a law for years, notes there is international precedent.

As its entry to World War II approached, the United States Congress sought to stave off the extinction of its national symbol and passed the Bald Eagle Protection Act, prohibiting the killing of the birds or the destruction their nesting grounds.

The laws, along with other conservation efforts, led to the numbers bouncing back and then climbing before, in 2007, the birds were removed from the endangered list.

Surely, says Ms Tabart, Australia’s concern for the koala matches America’s for the eagle.

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