Imagine someone in your neighborhood buying a salamander for a pet – an entirely unlikely scenario in a country that imports over 3.5 million amphibians each year. Salamanders are cute, small, and interesting pets, although they do require specialized care. They are suitable for small living situations and a world reduced by Covid.
Occasionally, however, one of these salamanders has a fungal pathogen. An owner may not know the animal is infected if it is asymptomatic or pre-symptomatic. But as everyone on Earth knows by now, asymptomatic and pre-symptomatic carriers can spread many diseases. Your neighborhood salamander owner might unwittingly release a sick pet, or even just dump infected pet water in the yard. Something like that, scientists say, is exactly what happened recently in California.
Batrachochytrium dendrobatidis, Where Comics, is a fungal pathogen chytrid – a dangerous skin fungus that spreads easily. It has now been found in two native California salamander species, a team of scientists wrote in late November in a journal article. Frontiers in veterinary medicine. The pathogen, which causes lesions, disruption of skin functions, lethargy, loss of appetite and ultimately death, is as deadly as it is resilient.
And its victims, the amphibians, are not as hardy as needed to succeed in a changing world. Twenty-five percent of the world’s species reside in the United States, more than 40 percent of which are already threatened with extinction. Amphibians absorb water through their skin, which makes them very sensitive to environmental changes in temperature or water chemistry. Strangely, Comics has the potential to infect not just one species, but most species of salamanders, and at least some frogs.
“We have only one species [of fungus] which is capable of infecting over 1,000 host species,” said Vance Vredenburg, a professor at San Francisco State University and one of the authors of the new paper. “It’s quite unusual, and it probably led to the extinction of several hundred host species.”
The researchers reported finding Comics in the tree salamander and the slender Santa Lucia mountain salamander. Because the fungus has such a wide range of potential hosts, it has the potential to affect all Bay Area salamander species, including the endangered California tiger salamander and long-toed salamander. from Santa Cruz.
The problem with salamanders is that they are much harder to study because they are more hidden, they don’t make noise so they are hard to find, but they are everywhere.
The question of the potential spread of a fungus through the pet trade is not new. In 2015, the Center for Biological Diversity called for a moratorium on the import of salamanders to protect native species from a related fungus called Basal. Fish and Wildlife then listed 201 species as “potentially harmful” in 2016, reducing imports by 98.4%. The Joint Pet Industry Advisory Council backed the ban. A 2017 study found no Basal in salamanders tested in the United States.
When it comes to comparable Comics, it is difficult to know which other species are affected and how much, since many hide beyond the perception of herpetologists.
“The problem with salamanders is that they’re much harder to study because they’re more hidden, they don’t make noise so they’re hard to find, but they’re everywhere,” Vrendenberg said. “They live these more burrowing lives, they don’t go out as much as frogs.”
While the current moratorium prohibits the import of 201 species of Asian salamanders due to the potential for spreading Basal, the risk of the disease spreading is so pressing that Center for Biological Diversity senior scientist Tiffany Yap said she believes all amphibian species should be carefully documented and proven pathogen-free before to enter the country, or prohibited.
“Ideally, wildlife trade is prohibited because we don’t have animals taken from their native habitat and introducing disease,” Yap said. “But a ‘clean trade program’ would put some limits on that trade. If amphibians are introduced into the United States, they must be tested for disease and proven free from Comics and Basal.”
Yap said some salamanders would enter the country without specific labelling: the packaging simply says “amphibian.”
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In an email, a spokesperson for the Pet Industry Joint Advisory Council said the trade organization also supports “wildlife trade moratoriums in situations such as the recently discovered fungus in two salamander species native to California, but only until a proper trade can be established.” The responsible pet care community is continuously committed to research to prevent and treat health problems in animals that pass through the trade and bans that provide for the permanent elimination of solutions in development are counterproductive and discourage this type of proactive investment.
The USGS calls salamanders “vital to ecosystem health,” for their role in controlling insect populations and for being meals for other animals higher up the food chain. A USGS map of risks to native salamanders of Basal shows that the risk to salamanders in the United States is particularly severe in parts of the Southeast, New York and coastal California, including the Bay Area.
Yap and Vredenburg note that the destruction of amphibians is both ecologically devastating and tragic. Entire ponds have had their populations wiped out, only to be filled with frog carcasses.
“The added stressor of this disease really gives them a number,” Yap said. “It would be really great if we could get increased biosecurity to help the native species that are still around.”