Apparently this is old news, but it’s the first I’m hearing it, and, well, frogs are pretty cool.
But:
The scientists then infected frogs
What’s your fucking problem, scientists? Find some sick frogs to cure instead of infecting healthy ones you sick fucks.
^Inside\ a\ “sauna,”\ heat\ helps\ frogs\ rid\ themselves\ of\ a\ deadly\ fungal\ infection^
Australia’s green and golden bell frog has suffered greatly from Batrachochytrium dendrobatidis (Bd), a fungus that has spread around the world over the past 3 decades. With its range reduced by 90%, the amphibian is teetering on the edge of extinction. Now, scientists have shown that small plastic-covered shelters can help the frogs warm up enough to kill the fungus, potentially rescuing the species—and maybe others—before it disappears.
“It’s a superinnovative and impressive paper,” says Brian Gratwicke, a conservation biologist at the Smithsonian Institution’s National Zoo and Conservation Biology Institute who was not involved with the work. “The implications are very hopeful.”
The approach, reported today in Nature, might improve the outlook for other frogs as well if the shelters could be distributed widely or put out in targeted efforts to help the last remaining populations of rare and endangered frogs, says Benedikt Schmidt, a conservation biologist at the University of Zurich, also not involved.
Bd wiped out the iconic harlequin frogs of Central America in the 1990s, causing the cloud forests to fall silent. Around the world, 90 species of frog have gone extinct, and even more have been pushed to the brink of vanishing, earning Bd the dubious distinction of the most harmful infectious disease of wildlife. The fungus spreads easily, often through the pet trade, infecting the skin of susceptible species and eventually causing heart attacks.
In the lab, antifungal medications can cure the disease. Keeping heat-loving frogs at 30°C also kills the fungus and can even assist some species in building immunity. But scientists have struggled to come up with practical ways to help animals survive the fungus in the wild. In a few heroic cases, scientists even temporarily removed the animals from remote ponds and disinfected the habitat.
Looking for a simpler approach, researchers have proposed putting small, heated enclosures into the field to allow frogs to warm themselves enough to kill the fungus. But no one had tested the idea.
Anthony Waddle, a conservation biologist at Macquarie University, wondered whether the approach might work with bell frogs. The animals like to climb into the holes of bricks, so Waddle designed a cheap, small greenhouse shelter that could surround these bricks and bring them up to 30°C. “I started to think, ‘What if the frogs can help themselves?’” he says. “Maybe all we have to do is give them an opportunity.”
First, Waddle and colleagues studied the bell frogs in the lab. They showed that when they infected animals with Bd, they preferred to be at 30°C. These frogs had milder disease than those kept at 19°C, which is an ideal temperature for the fungus. And frogs that could choose the temperature—by going in and out of various compartments in the housing—did even better, suggesting that being able to raise and lower body temperature is a particularly effective way for frogs to fight the fungus. The experiments also showed that, like some other species, bell frogs that had cleared an infection were better able to resist reinfection.
^The\ green\ and\ gold\ bell\ frog\ of\ Australia\ is\ an\ endangered\ species^
Moving outside, Waddle and colleagues created habitats in a dozen 3.5-meter-wide tubs. They added gravel, water, some artificial plants, and flowerpots for the frogs to hide in. Every tub also housed a shelter for the frogs consisting of a stack of black bricks, each with 10 frog-size holes. This shelter was enclosed in a small greenhouse, about the size of a lawn chair, wrapped in translucent plastic. The greenhouses heated up in the Sun and created a sauna effect inside. In a variation on this setup, the scientists also covered some of these greenhouses with shade cloth, which kept the temperatures inside cooler.
The scientists then infected frogs and put them in the tubs, observing them for several months and recapturing them every week or so to check for the severity of infection.
The sick frogs seemed to prefer spending time in the greenhouses rather than outside of them; they were seen there four times more often than would be expected by chance. The higher temperatures in the unshaded greenhouses helped them fight the infection, whereas the frogs in the slightly cooler shaded shelters had infections twice as intense. “I’m glad that we have a proof-of-concept study that show that the method could work for some species,” Schmidt says.
Waddle says he hopes the findings will lead to ways to help wild frogs. “I am extremely anxious about the outlook for the species.” He has a small grant to install frog shelters in Sydney Olympic Park, which has one of the largest remaining populations of the green and golden bell frogs. So far, he's put up 50, and he will track how the frogs do over the next few years. He also hopes to look at five to six other frog species in Australia that may benefit from the shelters, because they can tolerate temperatures high enough to kill Bd.
The approach could work for the many other species of amphibians that like to bask in the Sun and heat themselves, notes Schmidt, who specializes in amphibians with info fauna, the national data and information center for Swiss fauna. He would like to see a study where the shelters are deployed and the populations recover.
But Schmidt says it may not be easy to manufacture and distribute a lot of shelters, get landowner permission, or reach the entire range of a species. “The challenges of the transition from ‘it works’ to ‘it is now widely used’ should not be underestimated.”
