Scientists Save Frogs From Deadly Fungus With DIY Saunas

Scientists are so good at thinking outside the box to help animals in need. When one conservation method doesn’t work, they’ll try again and again to uncover what might help. Take the green and golden bell frog, for example. This frog species was in danger of dying out due to a vicious fungus, but new research figured out that a self-care treatment could actually save the ill amphibians!

What Is Happening to Frogs?

According to The Conversation, as many as 90 frog species are presumed extinct, and at least 500 frog species have declined due to a devastating chytrid fungus. This massive threat left researchers with few options, as gathering all the frogs and caring for them in captivity to prevent the spread of the fungus was not a practical solution.

Thanks to Anthony Waddle, an Australian conservationist and Schmidt Science Fellow at Macquarie University, and his team of researchers, there is a new solution to this problem. In a 2024 article published in Nature, they found that tiny frog saunas are actually helping to reverse the chytrid threat and save these green and golden bell frogs.

“Our purpose-built ‘frog saunas’ allow affected amphibians to warm up and bake off their infections,” Waddle wrote for The Conversation. “They are so simple you can build a frog sauna using supplies from the hardware store.”

What Does Chytrid Do?

The chytrid fungus will deplete electrolytes in a frog’s skin, leading to heart problems and potentially fatal cardiac arrest. Once it spreads into an ecosystem, it tends to stay, and because it’s so prevalent, it’s impossible to eradicate. Conservationists’ best bet is to figure out a way to help the frogs who have been infected, which is why this new study is so valuable.

Chytrid outbreaks are more common in colder months, much like how the seasonal flu affects humans. Since the fungus cannot survive in heat, the warm saunas kill the fungus and allow the frogs to recover.

Waddle and his team tested the frog saunas both in the laboratory and in outdoor experiments, using endangered green and golden bell frogs. Some frogs were allowed to choose between a warm, sauna-like environment and a cool, shaded area, while others were placed exclusively in either an always-warm or always-cold environment.

“We found frogs flocked to the sunny saunas, heated up their little bodies, and quickly fought off infection,” Waddle said about the frogs with the choice. “Think of frog saunas as little factories that pump out healthy, chytrid-resistant frogs.”

Amazing, right? He noted that the frogs in the always-warm environment also cleared the infection, but it took longer, and the frogs in the always-cool environment did not clear the infection.

“The frog saunas could be used on a wider scale. We believe they would be best suited to supporting populations of Australian green and golden bell frogs, but they could be useful for other species too,” Waddle added in the article for The Conversation.

How Are the Saunas Making a Difference?

These frog saunas are clearly making a big difference. In fact, Waddle won the 2025 Future for Nature Award for the impact this discovery has had on amphibians, and he is planning to use the prize money to expand the frog sauna project and encourage the public to build frog saunas. He also wants to encourage people to use apps like Frog ID to record and identify local frogs in the area.

“I am so excited that our work is getting attention and that folks are passionate about helping our struggling frog populations,” he told KUST Review.

In an August 2025 article in Nature, Waddle shared that frogs sitting in the heat of 28 degrees Celsius (or 82.4 degrees Fahrenheit) for just a few hours a day for about a week is all that’s needed to stop the fungus growth. Saving even one female frog can significantly impact the population, as a single adult can produce thousands of offspring in one season.

How to Build a Frog Sauna

To build a frog sauna, you’ll need 10 perforated masonry bricks, black furniture paint, and a small greenhouse. You’ll paint the bricks black to increase the amount of heat they can absorb, then arrange them with cable ties and put the greenhouse on top. It should be placed somewhere that frogs gather, like near a stream, with the ground underneath moist. The full tutorial can be found HERE.

Future Plans

So far, Waddle and the team have placed 70 frog saunas in three sites in Greater Sydney and will place more in three additional sites in 2026.

In the future, Waddle hopes to get into biodiversity and genetic engineering to figure out a way to genetically fix a frog’s reaction to this fungus and build resistance. This is especially important because the frog sauna method may not work for all frog species or in all climates, so a more permanent solution is needed.

But for now, finding this relatively inexpensive way to help save frogs is incredible, and we are so thankful for it. Now, even amateur wildlife lovers can make a big difference in wildlife conservation in their own neighborhoods. Simply make a trip to the hardware store, spend a little time assembling, and watch the local frog population grow!