Fungal diseases have hit species including frogs and bats, and now one is taking a toll on North American snake populations, National Geographic reports. Some 30 snake species in 15 US states and Canada have been hit hard by snake fungal disease, though rattlesnakes appear to be at particularly high risk, notably the endangered eastern massasauga. The disease causes lesions and blisters that when spread to a reptile's head can result in starvation. Since snakes hunt rodents, which spread ticks and parasites, their absence could lead to other problems. "This is especially important now, with talk of this being one of the worst Lyme disease years that we’ve had in a long time," biologist Jonathan Kolby tells National Geographic.
Fungal diseases that have also afflicted other animal populations remain mysterious. The disease is caused by O. ophiodiicola, a fungus identified in snakes as far back as 1880, though the fatal lesions began to appear only in 2000, per the BBC. How the pathogen spreads is unclear. "We don’t know where exactly they came from or why they suddenly appear to be more virulent," Kolby says. Another expert points to habitat destruction or cooler, wetter spring climates that drive snakes underground for longer periods where they are more vulnerable to infection. Kolby is concerned the US could be the source of the disease, which has also been spotted in captive snakes in England, Australia, and Germany. The pet trade may be spreading the pathogen unknowingly via clothing and boots, per Healthy Pets. (It turns out snakes are not "solitary and stupid.")