The Missouri Department of Conservation (MDC) recently received confirmation that a deadly disease in bats called “White-Nose Syndrome” (WNS) has been found in three bats from two caves in Lincoln County. The name describes a white fungus, Geomyces destructans, typically found on the faces and wings of infected bats. WNS spreads mainly through bat-to-bat contact and has not been found to infect humans or other animals.
WNS was confirmed in a little brown bat from one public cave and in two tri-colored bats from a second public cave north of St. Louis by the U. S. Geological Survey National Wildlife Health Center in Madison, Wis. The specific names and locations of the caves are not being disclosed to help prevent human disturbance of remaining bats in the caves. The two caves are closed to public access.
“Disturbing bats in caves while they roost or hibernate can increase their stress and further weaken their health,” said MDC Bat Biologist Tony Elliott.
Evidence of the fungus that causes WNS was first detected in Missouri in April 2010 on a little brown bat found in a privately owned cave in Pike County. In May 2010, evidence of the fungus was detected on five federally endangered gray bats and on a northern long-eared bat netted outside a public cave in Shannon County. The three bats with WNS in Lincoln County are the first confirmed cases in Missouri of the actual disease.
Elliot explained that the earlier detected cases of the fungus means the bats had contact with the fungus that causes WNS, but may or may not have been infected with the WNS disease. He added that these first confirmed cases of the disease mean the bats have WNS and the disease is present in Missouri and likely to spread.
“We have worked closely with the Missouri Department of Conservation to prepare for the arrival of White-Nose Syndrome in Missouri,” said U.S Fish and Wildlife Service Midwest Region Regional WNS Coordinator Rich Geboy. “Now that we have confirmed it is here, we will continue to work with MDC and our other partners in Missouri to research and manage the disease.”
MDC has been working with the Department of Natural Resources (DNR), Ozark National Scenic Riverways (ONSR), U.S. Forest Service (USFS) and USFWS, along with conservation groups and private cave owners to address the threat of WNS. Efforts include restricting access to most publicly-owned caves that contain bats and educating the public about the value of bats and the threat of WNS.
“While many caves on public lands that house bats have been closed to public access in response to the threat of White-Nose Syndrome, Missouri’s numerous show caves remain open as great places for people to discover nature by learning about the value of bats and the unique ecosystems of cave environments,” Elliott said.
Approximately 74 percent of the more than 6,300 caves in Missouri are privately owned. Visitors to private caves are asked to check with landowners before entering caves, and to use USFWS decontamination protocols before and after visits to reduce the risk for accidental spread of the fungus. Information on these protocols is available at fws.gov/whitenosesyndrome/pdf/WNSDecontaminationProtocol_v012511.pdf.
The WNS fungus thrives in cool, damp conditions found in many caves, which are also ideal hibernation and roosting sites for many bat species. Bats with WNS exhibit unusual behavior such as flying outside and clustering near entrances of caves and mines during the day in cold winter months when they should be hibernating. This activity uses up stored fat reserves needed to get them through the winter, and they may freeze or starve to death.
USFWS biologists and partners estimate that at least 5.5 million bats have now died from the disease, which continues to spread. WNS is decimating bat populations across eastern North America, with mortality reaching up to 100 percent at many sites. First documented in New York in 2007, the disease has spread quickly into 19 states and four Canadian provinces.
Bats provide tremendous value as natural pest control for farms and forests, and also play an essential role in helping to control insects that can spread disease to people.
“Missouri is home to at least 12 species of bats,” Elliott explained. “They are our front-line defense against many insect pests including some moths, certain beetles and mosquitoes. Missouri’s 775,000 gray bats alone eat more than 223 billion bugs a year, or about 540 tons.”
He added that bats are long-lived but slow-reproducing animals with most species having an average lifespan of about 15 years and giving birth usually to only one pup each year.
“Bats also play a vital role in cave ecosystems by providing nutrients for other cave life through their droppings, or guano,” Elliott said. “Bats are also food for other animals such as snakes and owls.”
Elliott cautioned that people should not handle any bats, and should contact their local MDC office or conservation agent if they find dead bats or see bats flying outside during the day during cold winter months when they typically would be roosting or hibernating.