Invasive Diseases

Bat White-Nose Syndrome

Help Us Prevent White-Nose Syndrome from Killing our Bats in the Pacific Northwest

Adapted from the Western Bat Working Group website:

Bat with White NoseSomething is killing whole wintering populations of bats in eastern North America as they hibernate in caves and mines. Bats are losing their fat reserves long before the winter is over and are dying of starvation. This affliction has been given the name white-nose syndrome (WNS) due to the telltale white fungus growing on the noses of some infected bats. Only recently described as a new fungal species, Geomyces destructans may also appear on the wings, ears, and/or tail membranes, but may also be absent.

White-nose syndrome (WNS) is not well understood and scientists are investigating all potential aspects of this mysterious disease. Geomyces destructans appears to infect hibernating bats as their bodies are cold and amenable to its growth. Infected bats may arouse from hibernation to attempt to deal with the fungal infection and in doing so prematurely burn up their fat stores and starve to death in midwinter. Affected bats have been observed flying outside during the day in winter, found dead or dying on the ground, or on buildings, trees or other structures during winter, or not arousing at all after being disturbed.

Bats Matter

Bats are an essential and beneficial part of the ecosystem. They play critical roles in insect control, plant pollination, seed dissemination, cave ecosystems, and provide food for other animals. There are 16 species of bats found in Oregon and Washington, most of which hibernate in caves. Hundreds and hundreds of caves exist on national forest land as well as other private and federal lands in Oregon and Washington.

How WNS Is Spread

Bat to Bat – Bat to bat transmission of Geomyces destructans has been documented in lab conditions and the geographic pattern of spread appears to support lab findings. It is also possible that other unknown agents associated with WNS are spread bat to bat.

Cave to Humans to Bats – Aspects of the geographic spread suggest that humans may transmit WNS from infected sites to clean sites. This kind of spread is most likely occurring from clothing and equipment that are not properly cleaned/decontaminated between sites. Formal testing of human spread WNS is ongoing. It is critical that people assume responsibility for the potential spread of WNS.

What Can I Do to Help?

  • DO NOT use gear (equipment, helmets, ropes, clothes, lights, boots, packs, etc.) in caves or mines that have been used in states with documented WNS or the Geomyces destructans fungus.
  • Decontaminate (clean) all gear if caving.
  • Observe cave closure periods on public lands.

Learn More about WNS and Decontamination of Gear, Boots, and Clothing on these websites: