White-nose syndrome

White-nose syndrome (WNS) is an emerging disease in North American bats which by 2018 has killed millions of bats in the United States and Canada. 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 in Schoharie County, New York. It has rapidly spread: By early 2018 it was found in 33 U.S. states and seven Canadian provinces and the fungus without the syndrome had been found in three more states. Most cases are in the eastern half of the continent, but in March 2016 it was confirmed in a little brown bat in the state of Washington on the West Coast. In 2019, evidence of the fungus was detected in California for the first time, although no affected bats were found. White-nose syndrome (WNS) is an emerging disease in North American bats which by 2018 has killed millions of bats in the United States and Canada. 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 in Schoharie County, New York. It has rapidly spread: By early 2018 it was found in 33 U.S. states and seven Canadian provinces and the fungus without the syndrome had been found in three more states. Most cases are in the eastern half of the continent, but in March 2016 it was confirmed in a little brown bat in the state of Washington on the West Coast. In 2019, evidence of the fungus was detected in California for the first time, although no affected bats were found. 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, and some species have declined >90% within five years of the disease reaching a site. The US Fish and Wildlife Service (USFWS) has called for a moratorium on caving activities in affected areas 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. As of 2012 white-nose syndrome was estimated to have caused at least 5.7 million to 6.7 million bat deaths in North America. In 2008 bats declined in some caves by more than 90%, Alan Hicks with the New York State Department of Environmental Conservation described the impact in 2008 as 'unprecedented' and 'the gravest threat to bats...ever seen.' In 2016, it was reported that bat populations in the caves and mines of Georgia had been decimated in a similar fashion, after the fungus was first detected in there in 2013. As of 2017, fifteen bat species, including three endangered species and one threatened species have been affected by WNS or exposed to the causative fungus, Pseudogymnoascus destructans, with impacts varying widely. As of 2012 four species have suffered substantial declines and extinction of at least one species was predicted. Declines included species already listed as endangered in the US, such as the Indiana bat, whose hibernacula, in many states, have been affected. The once-common little brown bat has suffered a major population collapse in the northeastern US. In 2012 the northern long-eared myotis (Myotis septentrionalis) was reported to be extirpated from all sites where the disease has been present for >4 years. In 2009, the Virginia big-eared bat (Corynorhinus townsendii virginianus), the official state bat of Virginia, and the gray bat had yet to suffer measurable declines. Beyond the direct effect on bat populations, WNS has broader ecological implications. The Forest Service estimated in 2008 that the die-off from white-nose syndrome means that at least 2.4 million pounds of insects (1.1 million kg) will go uneaten and become a financial burden to farmers, possibly leading to crop damage or having other economic impact in New England. It is estimated that bats save farmers in the U.S. 3 billion dollars annually in pest control services. In addition, numerous bat species provide crucial pollination and seed dispersal services. In 2008, comparisons were raised to colony collapse disorder, another incompletely understood phenomenon resulting in the abrupt disappearance of Western honey bee colonies, and with chytridiomycosis, a fungal skin disease linked with worldwide declines in amphibian populations. Biologists of the US Fish and Wildlife Service have been collecting information at each site in regard to the number of bats affected, the geographic extent of the outbreaks and samples of affected bats. They developed a geographic database to track the location of sites, where WNS has been found.The Fish and Wildlife Service has been partnering with the Northeastern Cave Conservancy to track movements of cavers that have visited affected sites in New York. In 2009, the Service advised closing caves to explorers in 20 states, from the Midwest to New England. This directive was supposed to be extended to 13 southern states. One Virginia scientist stated, 'If it gets into caves more to our south, in places like Tennessee, Kentucky, Georgia and Alabama, we’re going to be talking deaths in the millions.' In March 2012, WNS was discovered on some tri-colored bats (Perimyotis subflavus) in Russell Cave in Jackson County, Alabama.