Battle to save frogs from global deadly disease | Environment

Frogs, salamanders and toads all over the world are now being attacked by a growing number of interacting pathogens that threaten to devastate the global populations of amphibians.

This is the shouting warning from zoology experts that will gather this week in London in order to establish an emergency plan to save these endangered creatures. "Amphibians around the world are facing a new crisis, caused by attacks from multiple pathogens," said Professor Trent Garner of the Zoological Society of London, which hosts the conference. "We desperately need to devise strategies that can protect them."

Thirty years ago, experts noticed that amphibians were diving into different parts of the world. A new fungal disease, called chytridiomycosis, or simply chytrid, was beginning to wreak havoc among frogs and toads. At least 100 species have since been stricken from the surface of the planet. Among them, the golden toad of Costa Rica (Incilius periglenes) the southern gastric brood frog from Australia (Rheobatrachus silus) and Arthur's toad (Atelopus arthuri) in Ecuador. Hundreds of other species of amphibians have also experienced a severe decline – as a result of infections by the chytrid.

But scientists also know that the chytrid is not the only cause of amphibian deaths that are currently occurring in the world. Another pathogen known as ranavirus, which exists in at least four varieties, has been observed in amphibians. In addition, they discovered that there were at least two species of chytrid and many different genetic types.

"The bottom line is that these different pathogens do not act alone," added Garner. "They interact and, together, kill more and more amphibians. These interactions are often much worse than the effects of individual pathogens. "

In addition to the direct loss of species, reducing the number of amphibians is detrimental to the environment as frogs, newts and toads play an important role in maintaining healthy ecosystems. . For example, frogs eat mosquitoes that spread diseases. They also provide food for birds and other animals. In addition, tadpoles chew algae and thus help prevent the growth of algae. "To date, Britain has been very lucky," said Garner. "There has been no massive mortality recorded as in other countries – at least as far as chytrid infections are concerned."

However, ranaviruses are a different problem, he added. They caused declines in the common frog (Rana temporaria) in the United Kingdom, but also infect the common toad (Bufo bufo), often with fatal results. As a result, zoologists have asked the public to report sightings of sick or dead amphibians via websites such as Garden Wildlife Health and have also urged people not to move their eggs, tadpoles or frogs from a pool. to the other.

"So you avoid spreading infections," Garner said. "All you can do to reduce the pressure on these creatures is important."

In addition, this week's conference – Mitigating Isolated Pathogens and Coincidences Threatening Amphibian Biodiversity – will attempt to present ideas to try to save amphibians from the multipathogen-related threats they are now facing. "We will hold a one-day workshop where we will bring together the best people on the ground – environmental advocates, zoologists and co-infection experts – and inspire them to develop the best strategy." to deal with it. Unless you have one, the situation will worsen.