Center for Biological Diversity

For Immediate Release, March 31, 2016

Contact: Mollie Matteson, (802) 318-1487 or

Deadly Bat Disease Reaches Washington State

White-nose Syndrome Has Killed More Than 6 Million Bats in North America

SEATTLE— A highly contagious disease that has killed more than 6 million bats in North America has been confirmed in Washington state, wildlife officials said today. The discovery of the infected little brown bat — found by hikers on a trail about 30 miles east of Seattle — marks the first time the disease has been documented in the western United States.

The last known location of the pathogenic fungus, likely introduced to North America from Europe and discovered in 2006, was in eastern Nebraska.

“It’s shocking and disturbing to see this disease reach Washington and indeed the western United States,” said Mollie Matteson, senior scientist with the Center for Biological Diversity. “It certainly opens a new chapter in the spread of a disease that has already killed millions of bats. This is a wake-up call for land managers in the West to do what’s needed to keep white-nose syndrome from spinning out of control before it’s too late.”

White-nose syndrome has resulted in dramatic declines among several bat species, including the northern long-eared bat, little brown bat, tricolored bat and Indiana bat. It has been called the worst wildlife health crisis in recent memory, and has caused mortality rates ranging up to 100 percent among bats in affected caves. There is no known cure for the disease, which has afflicted seven bat species so far and has pushed several of them to the brink of regional extinction.

The disease is passed from one bat to another, or from the cave environment to bats, but it also likely spreads when people inadvertently carry it from one cave to another on their shoes, clothes or equipment.

Many leading bat biologists have emphasized precautionary measures, such as closures and site-specific caving gear requirements, as the best management response. The Center for Biological Diversity filed a petition in 2010 to close all caves and abandoned mines on federally controlled lands in the lower 48 states, keeping all but essential human activity out of caves. Such closures also would reduce disturbance of vulnerable hibernating or roosting bats.

“This disease just made a jump of more than 1,000 miles, so it’s pretty reasonable to think this could be a human-caused transmission,” Matteson said. “What’s absolutely heartbreaking about this news is that there were obvious things wildlife and land managers could have done to stem the spread, including prohibiting nonessential cave access into public land caves. They could have passed rules requiring that no caving gear or clothing from WNS-positive states be allowed in caves in unaffected states.”

Scientists have estimated the economic value of insect-eating bats to American agriculture at $22 billion annually. Bats also eat tons of insects harmful to forests, and their guano is essential to the survival of extremely rare cave organisms like cave salamanders and fish.

Learn more in this FAQ about white-nose syndrome.

The Center for Biological Diversity is a national, nonprofit conservation organization with more than 990,000 members and online activists dedicated to the protection of endangered species and wild places.

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