Will Trade Bans Stop a Deadly Salamander Plague from Invading the US? by Jeremy Hance 30 October 2018 Mongabay Series: Salamanders
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Will trade bans stop a deadly salamander plague from invading the US? By Jeremy Hance 30 October 2018 Mongabay Series: Salamanders · In 2008, scientists started noticing that populations of fire salamanders were disap- pearing in Western Europe. A few years later, nearly all had vanished from large portions of Germany, Belgium and the Netherlands. The culprit turned out to be a fungus called Batrachochytrium salamandrivorans, or Bsal, which infects the skin of salamanders and of- A wild rough-skinned newt (Taricha granu- ten kills them. Research indicates Bsal came losa) is swabbed for Bsal in Oregon. Photo from Asia and was spread to Europe via the courtesy of the U.S. Geological Survey importation of Asian salamanders. •The U.S. is home to the world’s highest di- versity of salamander species, many of which If it happens, it’ll likely go something like are thought to be susceptible to Bsal infec- this: American parents decide to buy some- tion. So far, scientists haven’t detected the thing special for their child’s birthday – a pet pathogen in North America, but many believe salamander. Although immediately excited, it’s just a matter of time until it gets here un- the child quickly loses interest and the sala- less drastic action is taken. mander languishes. The parents tire just as •In response, the U.S. Fish and Wildlife Ser- rapidly. One night, they let it loose outside, vice imposed a ban on the trade of 201 spe- telling their child it escaped. The salamander, cies of salamander species in 2016. However, little-prepared for the world beyond the ter- the recent discovery that frogs can also carry rarium, quickly perishes. But it leaves some- Bsal led to an outcry from scientists urging thing behind: spores of the deadly Batra- government to ban the import of all salaman- chochytrium salamandrivorans (Bsal) fungus. der and frog species. A decade later, salamander species in the U.S. •However, many hobbyists think a total ban are in crisis; populations are plummeting as is overkill. They instead favor a “clean trade” the fungus spreads, some species are believed in which some imported animals would tested totally gone. Extinction is marching across for Bsal. the land. Physical signs and symptoms from Batrachochytrium salamandrivorans (Bsal) infection: a) A naturally infected fire salamander (Salamandra salamandra) found during a Bsal outbreak in Belgium showing several ulcers (white arrows) and excessive skin shedding; b) extensive ulcer- ation (white arrows) on the belly of an infected fire salamander; c) skin section through an ulcer shows abundant fungal colonies inside the cells; d) further magnification of infected skin cells. Image from Pascale van Rooij et al., 2015, via Wikimedia Commons (CC BY 4.0). In an effort to stem this eco-tragedy, the U.S. At stake Fish and Wildlife Service (FWS) published a rule in January 2016 that banned 201 spe- In 2008, scientists started noticing popula- cies of salamander from being imported into tions of fire salamanders (Salamandra sala- the U.S. under the Lacey Act. But now some mandra) were vanishing from the wild in scientists — given new information about Western Europe. Five years later they were the spread of Bsal and its potential carriers able to officially describe the culprit, until — say this ban doesn’t go nearly far enough. then unknown to science: Bsal — a fungal disease that literally eats the skin off sala- “This deadly disease has the potential to manders. Closely related to Batrachochy- wipe out entire species. More needs to be trium dendrobatidis(Bd), which scientists done to protect salamanders and other wild- have implicated in hundreds of declines and life from international trade,” says Tiffany at least a few extinctions in frog species Yap, a staff scientist at the Center for Bio- worldwide, Bsal appears to only affect sala- logical Diversity (CBD) who specializes in manders. amphibian disease. Where it has hit — in parts of the Nether- She calls the USFWS listing “momentous” lands, Belgium, Germany — the fungus has but no longer up to speed with current scien- wiped out up to 99.9 percent of fire salaman- tific findings. ders. Others, including some herp (reptile and Researchers believe the European outbreak amphibian) hobbyists believe the USFWS is directly connected to the international pet rule may go too far and a different approach trade. is necessary. Scientists point to an animal that was im- It’s a debate about the legalities around pet ported in 2010 that three years later tested ownership and the strength and effectiveness positive for Bsal as at least indirect evidence of various regulations. that the first Bsal in Europe likely arrived via the pet trade. Research indicates Bsal How far do we go? stems from Asia, and salamander species there have evolved resistance to the disease When the USFWS banned 201 salamander after millions of years of co-evolution. Eu- species – about a third of all species – from ropean species have not — and lab studies being imported into the U.S., it was largely have shown that many U.S. species are also seen by scientists as a much-needed measure vulnerable. to do our utmost to prevent Bsal from getting onto North American shores. They did this by Scientists now fear the same fungal outbreak listing these species as “injurious wildlife” could wipe out salamanders across the U.S. under the Lacey Act, a conservation law that — if it arrives and gains a foothold. A recent regulates the trade in animals or plants. effort, testing 10,000 salamanders across the U.S., fortunately found no evidence of Bsal, Salamanders are strange. They’re strange not but it would only take one animal under a just because they can breathe through their worst-case-scenario to change that. skin, or because they can regenerate long limbs, or because they have a super long The debate over Bsal isn’t a debate over the genome. Salamanders are biological oddities science; it’s not a debate over how threaten- because they are found in their greatest diver- ing the fungal disease might be for North sity not in the rainforests of the Amazon or America’s salamander species — everyone the tropics of Southeast Asia, but in the decid- agrees that it could have a very destructive uous, temperate, and subtropical forests of the impact. eastern U.S. Unlike trees, beetles, birds, frogs or most terrestrial family you can think of, the “We take the threat very seriously,” said salamander doesn’t really prefer the tropics. Robert Likins, vice president of government affairs at the Pet Industry Joint Advisory Indeed, of the 600-700 species found world- Council (PIJAC). “If Bsal were to become wide, around 25 percent of them are found established in North America the results in the U.S. The U.S. includes representatives could be devastating.” from all families of salamanders with the exception of one – Hynobiidae, or primitive PIJAC is the world’s largest pet trade as- Asian salamanders. The U.S. hosts a particu- sociation, lobbying for pet-favorable laws larly large number of species that belong to across the U.S. Plethodontidae, a family that scientists think is one of the most susceptible to Bsal. The debate is really to what extent we should go to prevent it from happening and what’s the best strategy. Comprising nearly 400 species, Plethodon- Scientists have since discovered that a new tidae is by far the largest family of salaman- Bsal fungal spore can survive for up to 30 ders. Plethodontids, also called lungless days in the water or air and may even survive salamanders, breathe through their skin, on the feet of water birds, potentially travel- tend to be on the smaller side, and are found ing from waterway to waterway with ease. in a wide variety of habitats. Most species, like this tree-climbing arboreal salamander “These discoveries help to explain how Bsal (Aneides lugubris), are found in North Amer- can spread across landscapes and suggest that ica; scientists believe the first plethodontids it will be extremely difficult to eradicate it evolved in the eastern U.S. since non-susceptible species act as reservoir species,” reads a letter to the USFWS from a However, PIJAC felt the USFWS was tak- dozen experts about expanding the ban to all ing the wrong strategy in banning so many salamanders and frogs. salamanders. In 2015, PIJAC recommended an immediate and voluntary ban on the Chi- One of these experts was Reid Harris, the nese firebelly newt (Cynops orientalis) and Director of International Disease Mitiga- the paddletail newt (Pachytriton labiatus), tion at Amphibian Survival Alliance. Calling both from China, in a bid to keep Bsal out. Bsal, an “existential” threat to North Ameri- But Likins says PIJAC does not support the can salamanders, he agrees with Yap that all current ban because it “does not provide a salamanders need to be added to the banned mechanism for being lifted if an effective de- list. He says he doesn’t know of a “mecha- tection and treatment regimen is developed.” nism” to add new species to the list when new information comes out, but “there are a He added that “we do not believe that the lot more data now.” USFWS has the authority under [the Lacey Act] to ban vectors, making this an issue bet- Not just salamanders ter handled by USDA.” Last year, news hit that changed the debate But a year before the ruling, two conser- even further. Researchers discovered Bsal in vation groups, the CBD and SAVE THE a frog species in the pet trade in Germany.