OLYMPIA – White-nose syndrome (WNS) has been confirmed in a little brown bat (Myotis lucifugus) found near North Bend – the first recorded occurrence of this devastating bat disease in western North America. The presence of this disease was verified by the U.S. Geological Survey’s National Wildlife Health Center.
WNS has spread quickly among bats in other affected areas, killing more than six million beneficial insect-eating bats in North America since it was first documented nearly a decade ago.
WNS is not known to pose a threat to humans, pets, livestock or other wildlife.
On March 11, hikers found the sick bat about 30 miles east of Seattle near North Bend, and took it to Progressive Animal Welfare Society (PAWS) for care. The bat died two days later, and had visible symptoms of a skin infection common in bats with WNS.
PAWS then submitted the bat for testing to the USGS National Wildlife Health Center, which confirmed through fungal culture, molecular and pathology analyses that it had WNS.
“We are extremely concerned about the confirmation of WNS in Washington state, about 1,300 miles from the previous westernmost detection of the fungus that causes the disease,” said U.S. Fish and Wildlife Service Director Dan Ashe. “Bats are a crucial part of our ecology and provide essential pest control for our farmers, foresters and city residents, so it is important that we stay focused on stopping the spread of this fungus. People can help by following decontamination guidance to reduce the risk of accidentally transporting the fungus.”
First seen in North America in the winter of 2006/2007 in eastern New York, WNS has now spread to 28 states and five Canadian provinces. USGS microbiologist David Blehert first identified the unknown fungus, Pseudogymnoascus destructans, which causes the disease. WNS is named for the fuzzy white fungal growth that is sometimes observed on the muzzles of infected bats. The fungus invades hibernating bats’ skin and causes damage, especially to delicate wing tissue, and physiologic imbalances that can lead to disturbed hibernation, depleted fat reserves, dehydration and death.
“This finding in a far-western location is unfortunately indicative of the challenges we face with the unpredictability of WNS,” said Suzette Kimball, director of the USGS. "This underscores the critical importance of our work to develop tools for early detection and rapid response to potentially devastating wildlife diseases."
The U.S. Fish and Wildlife Service leads the national WNS response effort, working with state and federal partners to respond to the disease. The Service’s National White-nose Syndrome Coordinator Jeremy Coleman said the first step will be to conduct surveillance near where the bat was found to determine the extent of WNS in the area. The Washington Department of Fish and Wildlife (WDFW) is responsible for bat management and conservation in Washington and will coordinate surveillance and response efforts.
WDFW veterinarian Katie Haman said the disease is transmitted primarily from bat to bat, although people can carry fungal spores on their clothing, shoes or caving gear.
“The bat found near North Bend most likely had been roused from hibernation and was attempting to feed at a time of very low insect availability,” Haman said. “At this point we don’t know where the infected bat may have spent the winter, but it seems likely that it was somewhere in the central Cascades.”
Haman said Washington state has 15 species of bats that benefit humans by consuming large quantities of insects that can impact forest health and commercial crops.
WDFW advises against handling animals that appear sick or are found dead. If you find dead bats or notice bats exhibiting unusual behavior such as flying outside during the day or during freezing weather, please report your observation online at http://wdfw.wa.gov/conservation/health/wns or contact the WDFW Wildlife Health Hotline at (800) 606-8768.
To learn more about WNS and access the most updated decontamination protocols and cave access advisories, visit www.whitenosesyndrome.org.