A deadly fungus is spreading through Europe, and , unless we act quickly, it could ultimately spread beyond Europe—putting Salamander species native to North America in grave danger. Perhaps the problem is already beyond control, but a new paper in Science offers a simple solution: stop importing foreign salamanders.
Unfortunately, the government has yet to react to prior concerns. So, scientists from San Francisco State University, the University of California, Berkeley and the University of California, Los Angeles are now requesting prompt action to save these elusive creatures, who nonetheless play a vital role in the food chain.
The team is urging the U.S. Fish and Wildlife Service to immediately ban the import of live salamanders, until officials create a plan to detect and prevent the spread of the deadly fungus. Furthermore, they suggest that an international organization—not unlike the World Health Organization (WHO)—is needed to track traded animals and identify infectious diseases among wildlife, so that effective preventative measures can be taken.
"This is an imminent threat, and a place where policy could have a very positive effect," reported Vance Vredenberg, a biologist at San Francisco State University. "We actually have a decent chance of preventing a major catastrophe."
The fungus, Batrachochytrium salamandrivorans (Bsal), is related to the deadly Bd fungus that devastated amphibian populations across the world, only it is specific to salamanders. Believed to have originated in Asia and spread to Europe via the international pet trade, it wreaked havoc on European fire salamanders, with an astonishing fatality rate of 96%.
According to a Bsal webpage created by two researchers, Tiffany Yap, a UCLA graduate student, and Michelle Koo of the Museum of Vertebrate Zoology, Bsal attacks the skin of the salamanders, leading to lesions, anorexia, apathy, ataxia and death.
In the current study, the researchers combined three sources of data. First, based on knowledge gleaned from Asian habitats, they defined locations where Bsal could thrive in North America. Next, they considered the diversity of salamanders, assuming that the risk of infection is higher in areas with greater species richness. And finally they identified the location of major ports of entry based on trends in the recent salamander pet trade.
By comparing these three datasets, the researchers identified several regions that are particularly susceptible to Bsal infection in the North America. These include the southeastern United States (the southern Appalachian Mountains and surrounding), the western United States (the Pacific Northwest and Sierra Nevada), and the highlands of central Mexico.
"They're incredibly diverse, they've been around for tens of millions of years, and the thought of losing them because of human error, humans moving pathogens around by accident, is just a terrible thought," Vredenburg said. "And it's preventable."
Unfortunately, over 90 percent of the salamanders imported to North America come from salamander groups known to be carriers of Bsal. In an email, Yap explained that the disease can spread through direct contact with an infected animal, as well as potentially, through contact with waste water from an infected animal. The disease can then spread to wild populations if an infected animal is released into the wild, either accidentally or intentionally.
"As a community we can do a lot to help prevent the spread of this deadly pathogen. People should avoid buying salamander species from Asia for the time being, and pet owners should never release captive salamanders (or any pets) into the wild. Any waste water that has been in contact with captive salamanders should be treated with a very weak bleach solution (3-5% bleach) prior to disposal. Also, anyone (i.e., pet owners, importers) can have their animals tested for Bsal. Some treatments have been shown to clear Bsal infections, and these should be used if any animals are found to be infected with Bsal."