MADISON – Winter surveillance in 2014-15 for white-nose syndrome in bats has been completed, with 75 bat hibernacula visited for disease surveillance throughout Wisconsin.
In total, 14 sites in eight counties have been confirmed with either the disease-causing fungus or white-nose syndrome. Bats at sites in Grant, Crawford, Richland, Door and Dane county have tested positive for white-nose syndrome, while the fungus known to cause the disease has been confirmed at sites in Iowa, Dodge and Lafayette counties.
White-nose syndrome has spread to four additional counties from 2014 to 2015.
The original point of infection in Grant County has experienced an overall population reduction of 70 percent from pre-WNS estimates. At this time, this is the only affected location with a noticeable difference in population resulting from white-nose syndrome.
Although winter hibernation is over, the Wisconsin Department of Natural Resources will continue to review public reports and respond to wildlife mortality events in order to monitor the health of Wisconsin’s bat population.
White-nose syndrome is a deadly bat disease that, among other things, can cause bats to frequently wake from hibernation – this can deplete energy reserves and lead to starvation and dehydration, or death due to exposure before the end of winter. The syndrome was first detected in Wisconsin in Grant County in March 2014, and does not affect people or other animal groups.
Next steps in ongoing efforts to save bats
Efforts to control the human-assisted transmission of the fungus remain in place, including strict decontamination requirements for researchers and cavers, and efforts to educate commercial cave and mine visitors to help ensure they do not transport the fungus to other caves or mines. Every hibernaculum owner who allows visitors to their site has a white-nose syndrome plan in place.
The department has been actively exploring effective management strategies and continues to monitor bat populations and conduct research to fill information gaps. Through two Wisconsin Bat Program citizen-based monitoring projects (exit DNR), volunteers are helping to gather crucial data on bat population trends.
How citizens can help, including reporting sick or dead bats
Wisconsin citizens can help by continuing to avoid disturbing bats, especially during hibernation. It is important to remember that visitors to caves and mines could potentially transfer the fungus between sites, regardless of whether bats use the site for hibernation. If you are planning to visit a cave or mine, be sure to check with cave owners and follow white-nose syndrome procedures in place at any specific site.
People who observe sick or dead bats, especially between October and March, are encouraged to report them to DNR. A reporting form and instructions for how to safely collect carcasses of dead bats can be found on the department’s Wisconsin Bat Program (exit DNR) website.