The platypus, liberated from the pillowcase in which it had been traveling, headed straight for water.

The glossy platypus, along with two others, arrived at Tidbinbilla Nature Reserve, a 45-minute drive from the Australian capital of Canberra, on April 30. They had been sheltering at a zoo in Sydney. The cold, wet and windy day of their release could not have been more different from the day in late December when they had left the reserve.

Back then, Tidbinbilla was parched from extreme heat and drought and menaced by an approaching bush fire. Sarah May, the wildlife team leader for the reserve, and her crew were working long hours in thick smoke, trying to protect their lungs with face masks, their eyes red and burning. It was a grim and apocalyptic-feeling time, she said: “Fires had taken over everybody’s psyche.”

But the team worried most about their animal charges, the rare, endangered and iconic wildlife that make the reserve their home.

Tidbinbilla encompasses a eucalyptus forest, a broad valley full of emus and kangaroos, and a large wetland of ponds protected by a predator-proof fence. But in December the wetland, known as the Sanctuary, no longer resembled its name. Animals came to drink and forage from shrinking, muddy ponds, which were surrounded by large areas of dried, cracked earth.

The reserve contacted Taronga Zoo, in Sydney, asking if it had space to shelter its platypus population, aware that the animals would be unable to survive without their ponds. Taronga, which lists theplatypus as one of the “legacy species” it considers crucial to protect, was fielding similar requests from other conservation agencies, as well as farmers and landowners who saw platypuses struggling in drying creeks and ponds. “We were inundated,” Phoebe Meagher, the zoo’s wildlife conservation officer, said — but unfortunately, there was only so much space to house them.

The zoo agreed to send a rescue mission to Tidbinbilla. Because platypuses are active at dusk and at night, the team worked in darkness amid smoke was so thick that it was hard to breathe. After hours of trapping, they had caught seven platypuses. “The rest would have to take their chances,” May said.

In the following weeks, as the fires moved toward Tidbinbilla, the reserve looked for other temporary refuges to which it could evacuate its animals. Eventually, it moved six koalas; nearly 1,000 endangered northern corroboree frogs; 22 especially precious brush-tailed rock wallabies, whose genetics are key to a breeding program meant to re-establish a population that is nearing extinction in the wild, and 26 endangered eastern bettongs, which already went extinct on the mainland but are being reintroduced.

At Taronga Zoo, keepers were careful to keep the relocated platypuses wild: limiting their interactions with people, making sure they still had to burrow and catch their own food. The zoo also began to make plans for housing larger numbers of platypuses, should the need for evacuation arise again soon — something that climate projections suggest is likely.

And then, at last, rains returned, although they came so heavily that flash floods tore through fencing at the top of the Sanctuary. The ponds of Tidbinbilla refilled. The reserve tested the quality of the water to make sure it was not contaminated with fire retardants, and did surveys to make sure the ponds still held enough food. Finally, it was time to release the first round of platypuses and watch how they fared.

The returned platypuses were plumper, and different in another way as well: They had been implanted with tracking devices as part of a study to better understand how platypuses behave, how they respond to changes in their habitats, and how they are faring in Australia — which is still a very open question, said Gilad Bino, a researcher at the University of New South Wales who will be monitoring the Tidbinbilla platypuses.

His research suggests that platypuses, thanks to unsustainable water use and climate-driven drought, are actually in considerable trouble: extinct in 40% of their historical range, with bigger losses coming as climate change intensifies.

He warned that the story of happy news about the returned platypuses disguises a more alarming larger picture. “Rescuing platypuses from drying ponds is not really a viable strategy” for the species’ survival, he said. But the way things are going, he is sure that more rescues will be necessary.