White-Nose Syndrome is here.
The disease has reached the Northern Rockies. How cavers act now matters more than ever.
White-nose syndrome (WNS) is a fungal disease that has killed millions of hibernating bats across North America. It is caused by Pseudogymnoascus destructans (Pd), a cold-loving fungus that grows on the muzzles, ears, and wings of bats during hibernation, rousing them from torpor until they burn through their fat reserves and die before spring.
The disease was first identified in Schoharie County, New York in February 2006. In fewer than twenty years it has spread to more than 40 U.S. states and 8 Canadian provinces, and has been confirmed in at least 12 North American bat species.
WNS in the Northern Rockies
For years, western cavers held out hope that WNS would stall before reaching the Rockies. It did not. Pd and confirmed WNS are now established across much of our region, and the Grotto’s monitoring partners are documenting impacts in real time.
Regional timeline
- 2016 WNS confirmed in Washington state — the first detection west of the Rockies.
- 2020 Pd first detected in Montana.
- 2024 Pd documented in five species across 23 Montana counties; WNS confirmed or suspected in 10 counties.
- 2025 Idaho confirms WNS in bats from Bonner County. Montana FWP confirms Pd at Libby Dam — the first detection west of the Continental Divide in Montana. Surveys at Mystery Cave in the Pryor Mountains document a significant multi-year decline in bat numbers with several positive WNS cases.
- 2026 Oregon reports its first WNS detections in Yuma myotis and little brown myotis. Additional Idaho detections in Kootenai County.
What the Grotto is doing
The Northern Rocky Mountain Grotto partners with the USDA Forest Service Northern Region, the Montana Natural Heritage Program, Montana Fish, Wildlife & Parks, and the U.S. Fish and Wildlife Service to study bat populations and habitat across the region. Our members have contributed thousands of volunteer hours identifying and surveying bats in caves, mines, bridges, and other roost sites. Dozens of dataloggers and ultrasonic detectors are deployed around the region. Together, this represents the most comprehensive bat study ever conducted in Montana — and that baseline is exactly what’s needed now that WNS has arrived.
To reduce the risk of transporting the fungus, the Grotto maintains a set of loaner caving gear for visiting out-of-state cavers. If you’d like to borrow gear, use the Contact Us form at the bottom of the page.
NRMG members agree to:
- Use safe caving practices.
- Follow the current national WNS decontamination protocol on every trip.
- Report bat observations — including the absence of bats — within 30 days.
Stay current
Decontamination protocols and national surveillance updates change as the science evolves. Always check the official sources before heading underground:
- whitenosesyndrome.org — national WNS response, current decontamination protocol, maps.
- Montana FWP — White Nose Syndrome — state-level surveillance and annual reports.
- USGS National Wildlife Health Center — diagnostics and research.
Decontamination: the quick reference
Proper gear decontamination is the single most important thing a caver can do to slow WNS. The steps below summarize the National WNS Decontamination Protocol (updated March 2024). When in doubt, the protocol document is the source of truth — this is a field-ready summary, not a replacement.
After every trip — every time
- Remove visible mud and debris on site if possible. Rinse boots, pads, pack, rope, and harness with water before leaving the cave area.
- Bag contaminated gear for transport. Don’t mix it with clean gear.
- Submerge washable gear in hot water: 131 °F (55 °C) for at least 20 minutes. A large tote, a thermometer, and a kettle or on-demand hot water heater does the job.
- Launder clothing on hot for at least 10 minutes, or include it in the hot-water soak.
- Follow manufacturer guidance for helmets, lights, electronics, and rope — heat or chemical tolerances vary. If a piece of gear can’t tolerate the protocol, it stays in the region where it was last used.
- Dedicate gear by region whenever practical. The simplest decon is gear that never crosses a regional boundary.
Decontamination in the field (BLM, 2024)
This short video from the Bureau of Land Management follows a 2024 bat survey and WNS monitoring effort in New Mexico. It’s a good look at what agency biologists are doing in the field, and why decon matters.
Caver FAQ
Can I bring my rope and vertical gear from an affected state to Montana?
Not without full decontamination per the national protocol — and some gear (treated ropes, certain rubber components) may not tolerate the hot-water or chemical procedures at all. If in doubt, borrow NRMG loaner gear for the trip and leave your home kit at home.
Do I need to decontaminate between Montana caves?
Yes. Pd distribution within Montana is patchy and still being mapped. Decon between every cave — including between trips on the same day — is the current best practice, and it keeps Pd from hitching a ride into a site that hasn’t been exposed.
I last caved in an affected state years ago — is my gear still a risk?
Pd spores can persist on gear and in substrate for a long time. Gear that hasn’t been properly decontaminated since its last trip in an affected region should be treated as contaminated. When in doubt, decon it or retire it.
What if I only caved in a tourist / show cave?
Show caves are covered by the protocol too. Even if they provide their own mats or footwear rinses, follow the full decon on your own gear afterward.
What about bats I see on the surface — in a bridge, barn, or outbuilding?
Still report them. Roost sites outside of caves are part of the surveillance picture, and Grotto members commit to reporting observations (including absence of bats) within 30 days.
Report a sick, dead, or unusual bat
Do not handle bats with bare hands. If you find a sick, dead, or clustered group of bats — or bats in an unusual place (awake in winter, on the ground, outside in daylight) — report it.
Montana FWP Wildlife Health Lab (Bozeman): 406-577-7882
Or contact your local FWP office biologist.
Montana FWP is especially interested in clusters of dead bats and any bats found dead in winter or early spring. For Idaho, contact Idaho Fish and Game; for Wyoming, Wyoming Game and Fish.
NRMG members: please also note observations in the member reporting system within 30 days, per your membership pledge.