White-nose syndrome
White-nose syndrome (WNS) is a fungal disease in North American bats which has resulted in the dramatic decrease of the bat population in the United States and Canada, reportedly killing millions as of 2018.[1] The condition is named for a distinctive fungal growth around the muzzles and on the wings of hibernating bats. It was first identified from a February 2006 photo taken in a cave located in Schoharie County, New York.[2] The syndrome has rapidly spread since then. In early 2018, it was identified in 33 U.S. states and seven Canadian provinces; plus the fungus, albeit sans syndrome, had been found in three additional states.[3] Most cases are in the eastern half of both countries, but in March 2016, it was confirmed in a little brown bat in Washington state.[4] In 2019, evidence of the fungus was detected in California for the first time, although no affected bats were found.[5]
The disease is caused by the fungus Pseudogymnoascus destructans, which colonizes the bat's skin. No obvious treatment or means of preventing transmission is known,[6][7] and some species have declined >90% within five years of the disease reaching a site.[8]
The US Fish and Wildlife Service (USFWS) has called for a moratorium on caving activities in affected areas[9] and strongly recommends to decontaminate clothing or equipment in such areas after each use. The National Speleological Society maintains an up-to-date page to keep cavers apprised of current events and advisories.[10]