Wildlife conservation advocates call for more stringent measures
By Bob Berwyn
The fungal infection has wiped out millions of bats in the Northeast, spreading southward, and west as far as Oklahoma, but hasn’t yet reached the Rocky Mountains, but the Forest Service recognizes the threat:
“If (the disease) is introduced to cave or (abondoned mine) habitats anywhere in the five states in Region 2, it will likely spread rapidly via bat-to-bat transmission and could quickly contaminate cave and (abandoned mine) habitats,” the agency concluded in the study.
Bats play a huge role in suppressing insect populations and pollination plants. By some estimates, the value of bug-eating bats to U.S. farmers ranges from $3 billion to $53 billion per year. Bats eat enormous quantities of moths, beetles, mosquitoes and other insects, and their absence could make farmers and others decide to use greater quantities of expensive, and potentially harmful, pesticides.
The Forest Service hopes to prevent the disease from spreading into the Rocky Mountain Region by closing seasonally caves where bats hibernate and by banning clothing and gear used in areas where white-nose syndrome is confirmed or suspected. The agency will also use a registration system to track cave visits and require year-round decontamination procedures for caves that are known hibernacula.
If the fungal pathogen moves closer, caves would generally be closed. The Forest Service set a threshold distance of 250 miles based on input from biologists with other federal agencies. There would be some exceptions to the Tier 2 closures, but decontamination would be required of all cave visitors.
The proposed management plan, outlined in an Environmental Assessment, doesn’t go far enough for some conservation advocacy groups, who see it as a weakening of existing protections for bats.
“This decision is a terrible blow to efforts to forestall the spread of this wildlife epidemic to the West,” said Mollie Matteson, a bat specialist at the Center for Biological Diversity. “It’s extremely short-sighted, giving priority to the recreational interests of a small group of people over the survival of western bats,” Matteson said, referring to cavers, a small but vocal minority of national forest users who have been intensively lobbying the Forest Service to maintain access.
Under the precautionary principle, Matteson has advocated for strict cave closures at least until more is known about how White-Nose Syndrome spreads.
Cavers say the only proven method of WNS transmission is by physical bat to bat contact, according to U.S. Geological Survey research.
“Unfortunately, to date … hard science is telling us we may not be able to do anything about this disease, except to help affected colonies recover,” the National Speleological Society‘s Peter Youngbaer wrote in a comment on a previous Summit Voice story.
“It’s time we stopped listening to the fear-mongering being spread by the Center for Biological Diversity, calling for over-reaction by federal and state land management agencies, and allowed our responses to be driven by hard science,” Youngbaer wrote, calling for a nuanced, science-based approach to management.
“Scientists are working frantically to find a cure for this unprecedented wildlife die-off,” said Matteson. “It’s a race against time, because once the disease spreads into the vast reaches of the West, it may well be too late. Federal land managers need to do everything they can to reduce the risk of humans spreading this disease to western caves.”
Biologists say bat-to-bat infection is the most likely path for the disease, but they also believe the humans could spread the fungal spores, enabling the disease to make bigger geographical jumps.
The Forest Service study acknowledged the potential for the spores to be spread by humans, said Trey Schillie, who coordinated the agency’s study:
“While the risk and probability of human-caused spread of (the fungal pathogen) is debated by some, the fungus can be transmitted on clothing and equipment and can be cultured from very little soil. This means humans can move (White-Nose Syndrome) from cave to cave on their gear,” the agency concluded.
Schillie said the Forest Service will ban the use of caving gear from any state where white-nose syndrome has been spotted. Forest supervisors also have the option of requiring full decontamination procedures for cave visitors, he added.
According to Schillie, the real key to preventing the spread of white-nose syndrome will be education and partnership with cave visitors. The plan outlines a registration system enabling the Forest Service to learn more about how and when people visit the caves.
About a dozen bat species in the Rocky Mountain region use caves and abandoned mines as hibernation roost sites. The Forest Service focused in part several regional bat species classified as sensitive, including Townsend’s big-eared bat, fringed myotis, spotted bat, and hoary bat.
The Rocky Mountain region is also home to four bat species known to be affected by the disease: Little brown myotis; big brown bat; northern long-eared bat; and tri-colored bat. Other bat species in the region (primarily those of the genus Myotis) also hibernate in caves and could be susceptible to the disease.
Several national forests in the region have already formally adopted rules based on the regional study. More details are available at this Forest Service website.