White-Nose Syndrome Kills ND Bats Near MT Border

So far, Montana Fish, Wildlife & Parks hasn’t found signs of the deadly white-nose syndrome (WNS) in the state’s bat populations, but biologists are closely monitoring the situation. Recent reports of bat deaths from WNS just over the border in North Dakota make monitoring efforts even more critical.

“Bats provide important services in protecting crops and timber from flying pests,” said Lauri Hanauska-Brown, Montana FWP nongame wildlife management bureau chief. “Bats also eat tons of mosquitoes each year, meaning they play a role in reducing the spread of some mosquito-borne diseases. Like we do for all wildlife, we are doing what we can to keep bat populations healthy.”

WNS has been in North America since at least 2006, killing an estimated 6.7 million bats. A powdery white fungus grows on the skin of hibernating bats, often on the face – hence the name “white nose.” The fungus causes a number of problems, one of which is that it irritates bats, causing them to arouse early from hibernation and search for water and food. Food is obviously scarce in winter, and this early arousal can exhaust fat stores that bats need to survive the winter.

WNS has been confirmed in 35 states and seven Canadian provinces. It can wipe out entire colonies of bats and has caused dramatic population declines in eastern states.

This month the North Dakota Game and Fish Department reported a cluster of little brown bat deaths from WNS just over the Montana border. The first week of May, the department learned of at least 20 dead bats found in Medora. Six were submitted to the USGS National Wildlife Health Center in Madison, WI. for analysis. The bats all tested positive for the fungus Pseudogymnoascus destructans, the culprit behind WNS.

“This is the second time that the fungus has been detected in the state, but these are the first documented deaths in bats attributed to WNS,” said NDGFD Conservation Biologist Patrick Isakson, while noting it was roughly a year ago that the fungus was found on a live bat within the boundary of the Knife River Indian Villages National Historic Site.

FWP has temporarily prohibited the capture of all live bats due to unknown risks of COVID-19-infected humans inadvertently transferring the virus to bats. To substitute for sampling of live bats, the collection of bat droppings at eastern Montana roosts has begun to look for signs of WNS. Biologists are visiting known roost areas, including the undersides of bridges, and collecting samples. WNS is not known to affect humans, pets, livestock or other wildlife.

“The discovery of white-nose syndrome in these bats signals the continued expansion of this invasive pathogen through North America,” said Jeremy Coleman U.S. Fish and Wildlife Service national white-nose syndrome coordinator, which leads the national response to WNS. “It also highlights the need for continued vigilance to track the spread of the disease and the impact it is having on native bat populations so we may better focus our conservation efforts.”

State and federal agencies are asking for help to monitor the spread of this disease. Anyone seeing a dead or sick bat, or group of bats, is asked not to handle them, but to notify health officials or state biologists, who can provide further guidance. Callers can reach Montana Fish, Wildlife & Parks at 406-228-3725 in FWP’s Region 6, or at 406-234-0948 in FWP’s Region 7.

“Like other wildlife, bats can be sick or die for a variety of reasons,” said Emily Almberg Montana FWP disease ecologist. “We are particularly interested in investigating clusters of dead bats or bats that are found dead during the winter or early spring.”

For more information, visit https://www.whitenosesyndrome.org/.