Deadly white-nose syndrome still unchecked
By Summit Voice
Hoping to prevent the westward spread of a deadly bat disease, the U.S. Forest Service last week extended a general closure for caves on national forest lands in the Rocky Mountain region (Colorado, Wyoming, South Dakota, Nebraska and Kansas) for another year.
The agency tweaked the closure slightly to rovide exemptions to active members of the National Speleological Society and Cave Research Foundation for activities consistent with national agreements with both organizations.
“Our priority is to protect bat species and habitat from the westward spread of WNS, a deadly disease that has killed 5.5 million bats since 2006,” said Daniel Jirón, regional forester, U.S. Forest Service, Rocky Mountain Region. “The fungus has not yet been detected within the five-state Rocky Mountain Region and we are taking an aggressive approach to minimizing the risk of humans inadvertently introducing the fungus into our caves and abandoned mines,” Jiron said.
“The Forest Service values the expertise of the caving community and views them as stewards of important cave resources and habitat,” he added, explaining the exemptions. The agreement with caving organizations allow for education, inventory, research, monitoring, protection, restoration and other activities necessary to conserve cave resources. Access will not be granted to caves during the winter hibernation season, when bats are most susceptible to exposure.
There are about 30,000 abandoned mines and hundreds of caves on National Forest System lands throughout the Rocky Mountain Region. Caves on National Forest lands in the region support about 21 species of bats; 15 of which are hibernating bats. Once a colony is infected, it spreads rapidly and can kill over 90 percent of bats within the cave in just two years.
Scientists are certain transmission of WNS is occurring bat-to-bat and cave-to-bat. Scientists also suspect transmission of WNS may be facilitated by human activity in caves where bats hibernate, because of the geographically discontinuous spread of the fungus. People may be transporting fungal spores from cave to cave, as fungal spores have been detected on gear exposed to affected sites.
WNS is named for a white fungus that appears on the faces, ears, wings, and feet of hibernating bats. The disease causes bats to come out of hibernation severely underweight, often starving before the insects on which they feed emerge in the spring.
Conservation advocates said the Forest Service policy will help protect western bats.
“In just six short years, white-nose syndrome has spread across most of the eastern United States and wiped out as many as 7 million bats,” said Mollie Matteson, a bat advocate with the Center for Biological Diversity. “This cave closure is the minimum needed to try and prevent further spread of a horrible epidemic.”
The disease first appeared in upstate New York in a cave connected to a popular tourist cave. To date, white-nose syndrome has spread to 19 states and four Canadian provinces. The fungus that causes the disease has been detected on bats as far west as eastern Iowa and western Oklahoma.
Bats and people are capable of transporting the fungus, which is believed to have originated in Europe. But unlike bats, humans are able to transport the fungus long distances. Biologists fear the bat malady will leapfrog into the western United States, where many more new bat species may be susceptible to the disease.
“If cavers are following the strict decontamination procedures against the fungus, and they are doing specific work to assist in furthering understanding of bats, the policy could be helpful,” said Matteson. “But if there is poor enforcement of the closure and exemptions, it could lead to abuse and increase the risk that white-nose syndrome will make a disastrous leap into the West.”
In the western United States, an emergency cave closure has been put in place only in the Rocky Mountain Region of the Forest Service.
On other federal lands in the West, including virtually all lands under the jurisdiction of the Bureau of Land Management, as well as the other regions of the Forest Service, most caves and other bat roosts and hibernation sites remain open to unlimited human access. The U.S. Fish and Wildlife Service ended public access to all caves on its wildlife refuges in 2011, and the National Park Service has tightened public access to caves in parks.
”Cave closures are needed throughout the West,” said Matteson. “The loss of millions of bats is a terrible tragedy that has real consequences for people who depend on them to keep insect pests in check.”