Salamanders and newts across Europe are threatened by a skin eating fungus that probably arrived on pet amphibians imported from Asia as said by zoologists.
In 2013 the fungus was discovered in the Netherlands and wiped out all but only 10 of the country’s fire salamanders. The fungus causes deadly skin diseases in many related species but not those from Asia as shown in the tests.
Batrachochytrium dendrobatidis is a type of fungus related to the parasite fungus called Batrachochytrium salamandrivorans which causes a similar disease in frogs and other smphibians, mostly in the tropic.
The recently discovered ‘B.sal’ does not affect frogs or toads but kills a wide variety of salamanders according to the new study. Though it helps to breath, it rapidly invades and eats an animal’s skin which is crucial to its survival.
“Most of the salamander species that come into contact with this fungus die within weeks,” said lead author Prof An Martel from Ghent University, Belgium.
“There appear to be no real barriers that prevent the spread of the fungus throughout Europe.”
More than 5,000 amphibians from 35 different species across four continents were screened by Prof Martel and her team. The outcome pointed the finger squarely at Asia as the most likely source.
“It’s extremely lethal to most of the European salamanders that we tested, but it doesn’t seem to cause serious disease in any of the Asian species,” said Dr Trent Garner from ZSL’s Institute of Zoology.
“The best explanation we have right now is this fungus originally arose in Asia.”
The team estimated that this branch of the family has lived with the fungus since the Palaeogene period, 30 million years ago though it was revealed that it can carry the fungus but survives based on the evolutionary history of the group of Asian salamanders.
Since several species of Asian newts and salamanders are popular pets in Europe and the US, the animal trade seemed a likely explanation for the fungus turning up in Belgium
The animal trade seemed a likely explanation for the fungus turning up in Belgium since several species of Asian newts and salamanders are popular pets in Europe and the US.
The researchers also examined more than 2,000 skin samples from animals in museums and in pet shops around Europe, including Heathrow Airport and at an export business in Hong Kong with the view to test this idea.
The pet shop samples were found to be clean, but three specimens kept in European museums were found infected – and had been imported from Asia in 2010.
The Chinese fire-bellied newt, Cynops orientalis, which is such a common pet worldwide that 2.3 million of themarrived in the US between 2001 and 2009, is believed to be the likely culprit.
Dr Garner was keen to defend the newts themselves.
“Let’s not call it a villain,” he told the BBC. “They’re not jumping onto aeroplanes of their own volition. Let’s call it the poor, trafficked amphibian.”
He also explained that the invasion could be controlled by careful management.
“We’ve got to work towards controlling pathogens in the wildlife pet trade,” Dr Garner said.
“Moving animals around moves their pathogens with them. Quite often in new situations, these pathogens have the weapons to overwhelm local hosts that haven’t been exposed.”
He also claimed that efforts should be made to tackle the fungus in the wild.
“It’s no longer a matter of populations just going down – we’re actually seeing species being eliminated by new infectious diseases.
“I personally think that we can develop these mitigation techniques – we do it for livestock and we do it for humans.”