Officials begin testing samples from bat caves
By Daniel Patrick Sheehan
ALLENTOWN, Pa. — Has a sinister, bat-killing disease made its way to Pennsylvania?
Officials aren’t sure, but last week they began collecting and testing samples from bat caves and mines in Fayette, Blair and Luzerne counties, seeking signs of the illness that has caused massive bat die-offs in New York, Vermont, Massachusetts and Connecticut.
The disease, called white-nose syndrome, is named for the ring of white fungus typically found around the noses of affected bats, which unaccountably lose the body fat needed to survive hibernation and can starve to death in their winter homes.
The U.S. Fish and Wildlife Service has called it an ecological disaster in the making, because bats — voracious insect-eaters that keep mosquitoes and other flying pests in check — produce only one offspring a year, meaning they can’t compensate for the die-offs.
Like the "colony collapse disorder" that has afflicted honeybee populations in recent years, the syndrome has confounded scientists. It is unclear whether the fungus is the cause of the bat mortality or a symptom of it, because not all affected bats have the telltale nose ring. It is also unclear whether the fungus poses a health threat to people.
"Anytime you have a disruption in the system with one species dying, you don’t always know the ramifications of that death," said Diana Weaver, a spokeswoman with the Fish and Wildlife Service. "We don’t know how this spreads — if bats are spreading it, if other creatures can carry it — and we’re very uncertain right now about what’s going on."
Pennsylvania has about 1,000 caves and mines that harbor bats. One of the largest is the Durham Mine in upper Bucks County’s Durham Township. It is home to 5,000 to 10,000 bats from a half-dozen species. No signs of the illness have been detected there since the Heritage Conservancy, which owns the property, began monitoring over the winter.
Elsewhere in the state, "We have taken samples of bats at three locations and have not yet received the results from those samples," said Jerry Feaser, press secretary for the Pennsylvania Game Commission. "We do not have white nose confirmed in Pennsylvania at this time."
He urged restraint in reporting on the matter because there have been no die-offs and Pennsylvania bats have not exhibited other signs of the illness, such as flying outside during the day in winter or clustering near the entrances to hibernation areas. The syndrome is also not the only cause of white fungus on hibernating bats.
"For all we know the bat may have flown into a powdered doughnut," Feaser said. "Not to make light of it, but it has not been confirmed in Pennsylvania."
A conservation official in New York — where the syndrome was first identified in 2006 and where an estimated 11,000 bats succumbed last year in four Albany-area caves — called it the gravest threat to bats researchers have ever seen. Mortality in some New York caves was 80 percent to 100 percent.
Little brown bats are sustaining the largest number of deaths, the service said. Also dying are northern long-eared and small-footed bats, eastern pipistrelle and the federally protected Indiana bat.
Fearful that human activity could spread the disease, officials in affected states — and some unaffected ones, including New Jersey — have asked people not to enter caves or mines known to harbor bats. Feaser said Pennsylvania officials are debating whether to close caves beyond the ones routinely closed t