Thu. Oct 6th, 2022

Nearly 100 species of amphibians were wiped out by the fungal disease

A fungal disease caused by two species of fungi has already affected more than 500 amphibian species worldwide and is responsible for the extinction of 90 of them, according to a new study. The epidemic has been raging since the 1980s. last century and was probably caused by humans.

Chytridiomycosis attacks skóhand of frogs, toads, salamanders and other amphibiansóin the tailed. It is caused by two species of the fungus: Batrachochytrium dendrobatidis i Batrachochytrium salamandrivorans. These fungi usually live in soil and water, where they decompose dead organic material. Fungus-infested animals have trouble regulating electrolyte levels properlyóin the epidermisórku. There is a significant reduction in the blood serum concentration of ionóin potassium and sodium, leading to cardiac arrest and death.

Chytridiomycosis is present in 60 countries around the world. It has caused the most damage in Australia and Central and South American countries. The findings of an international team of scientistsów have been published in the pages of the journal „Science”.

– The global impact of the fungus is striking. It’s almost like Hollywood. We love these videos about pathogens, whichóre appear suddenly and devastate humanity. This is exactly what we are seeing with regard to amphibiansóIn the real world – said Stephen Price of University College London.

Chytridiomycosis has already affected more than 500 species worldwideóin amphibianów causing a significant decline in their population. Researchers argue that it is responsible for the extinction of 90 species ofóin the amphibianów. Other well-known pathogens, such as white nose disease affecting bats or West Nile virus, whichóry kills birds, affected only a fraction of the number of species ofów. The impact of these twoóch speciesóin the fungus on bioróThe diversity is cfócomparable to the impact of the most destructive species of theóInvasive species, such as cats and rats.

– Disease is caused by a fungus thatóry probably originated in Asia, where local amphibians appear to have immunity to the disease, said Dr. Ben Scheele of the Australian National University, head of theówny author of the study. – Highly virulent wildlife diseases, including chytridiomycosis, contribute to shóstego mass extinction. The disease we studied caused the mass extinction of amphibiansóIn all over the world. We have lost some truly amazing speciesów – added Dr. Scheele.

Researchers believe the disease was spread around the world by wildlife traffickers. Its epidemic was noted in the 1980s. last century, but until now no one has taken próto take stock of the destructive activities of the fungus. Scheele has assembled a compositeół 41 expertów from around the world to assess the scope of the problem.

Each of the researchers involved has collected evidence of które amphibian speciesóin have been affected by fungi in their region, searching the scientific literature and unpublished data, as well as interviewing other experts. Losses ranged from about 20 percent. of a given population until the extinction of the entire species.

In Europe, the disease has affected only a few speciesóin the amphibianów. Perhaps, the fungi responsible for the epidemic got here earlier. Massive declines in amphibian numbers have been reported on the Old Continentóin the 50s. i 60. In the 1970s. These have been attributed to agricultural intensification, but it is possible that the mushroom was in this róalso involved.

– Globalization and wildlife trade are the mainóin the root causes of this global pandemic and enable the further spread of similar diseasesób. Humans are moving plants and animals around the world at an ever-increasing rate, introducing pathogens to new areas – explained Scheele. The researcher acknowledged the urgent need to improve the recipeóin biosecurity and wildlife trade to prevent further species extinctionsów. – We must do all we can to stop future pandemics through better control of wildlife trade around the world – added the scientist.

Studies have shown that many species are still endangeredów. We will continue to see declines in amphibian populations over the next 10-20 years due to chytridiomycosisów. Unfortunately, the fungus, whichóry once it has entered the ecosystem it will already remain there, and this is because not all species are killed by the disease. – On the one hand, it is fortunate that someóre species are resistant to the fungi, but on the other hand, this means that these species carry the fungi and are a reservoir for them, so there is a constant source of the disease in the environmentódło diseases – explained Scheele.

Sourceóbackground: Nature, Australian National University, photo. CC BY 2.5/ Wikimedia Comons/ Forrest Brem