White-nose syndrome (WNS) has been confirmed in a little brown bat (Myotis lucifugus) found near North Bend in April – 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.
“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.
Transmission and precautions
Washington Department of Fish and Wildlife (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 to WDFW online or call the WDFW Wildlife Health Hotline at 800-606-8768.
The Washington Department of Fish and Wildlife (WDFW) is responsible for bat management and conservation in Washington and will coordinate surveillance and response efforts.
To learn more about WNS and access the most updated decontamination protocols and cave access advisories, visit www.whitenosesyndrome.org.