|Biologist Susi von Oettingen photographed these bats in a Berkshire County mine. (US Fish and Wildlife Service)|
A mysterious and deadly sickness that has killed off thousands of bats in New York has now been discovered in two Western Massachusetts mines.
Researchers say they expect to find more affected wintering bat populations as they lead expeditions into dark caves and mines in the Northeast over coming weeks. They predict that hundreds of thousands of the furry creatures will be wiped out before the end of winter.
The illness - known as white nose syndrome, because some afflicted bats have a white fungus on their noses - does not appear to pose any risk to people, but the US Fish and Wildlife Service is asking the public to stay out of caves and mines in the Northeast because humans may be inadvertently transmitting the sickness to bats.
"No one has a clue what is going on," said Tom French, assistant director of the natural heritage and endangered species program of the Massachusetts Division of Fish and Wildlife, who helped find sick bats in Massachusetts.
As French and other researchers parked their cars near the Chester mines last Friday, they saw several bats, which normally hibernate all winter, flying outside in daylight. Others were found dead nearby, frozen onto houses, in tree branches, and in the snow. Far larger numbers were behaving strangely inside the mines, clustering near the entrance, instead of hibernating deeper in it.
Bats fill an extraordinarily important ecological niche. In New England, they eat insects that can infest crops and pester people. There are nine bat species in New England, and researchers say populations probably number in the hundreds of thousands.
Bats can live 25 years or more and generally give birth to one offspring a year, raising scientists' concerns that the illness could devastate the region's bat populations. Mortality has reached as high as 97 percent in some caves. In one New York cave last year, bat populations crashed from 1,300 animals to 38.
Scientists say they believe that most bat species are vulnerable, but only four species have been found with the syndrome: little brown bats, Northern long-eared, Eastern pipistrelle, and the federally endangered Indiana bat.
The disease was first discovered in a cave near Albany in January 2007 and was soon found in three more caves within seven miles. By last March, New York officials determined that as many as 11,000 bats had died.
This year, scientists found the disease in the original four caves, as well as in many more caves and mines within about a 150-mile radius, housing roughly 500,000 bats. Bats in Aeolus Cave in Dorset, Vt., were discovered with white nose syndrome last week. Two days ago, officials from The Nature Conservancy found bats with the syndrome in a Hague, N.Y., mine where about 185,000 bats are believed to hibernate.
Researchers have not found enormous numbers of dead bats yet, but say that, based on a smaller outbreak of the disease in New York last year, the animals will probably start dying by the thousands next month. "We just don't know how this is going to play out elsewhere" in the country, said Alan Hicks, a bat specialist with the New York Department of Environmental Conservation.
Researchers from Virginia to New Hampshire are examining mines and caves for evidence of the syndrome. Meanwhile, about 15 university, government, and private labs are attempting to diagnose the sickness.
Researchers know that the animals get the white fungus, but are unsure if it is a cause or a result of the disease. They also know that the animals are starving; the dead ones have no fat on them. Pathology labs have said that some of the animals also seem to have pneumonia-like symptoms.
"Were they fighting off a flu or a cold or some unknown illness that weakened them before they went into hibernation?," said Susi von Oettingen, an endangered species biologist with the US Fish and Wildlife Service. "Is it a disease? Something else? We don't know how it's transmitted."
Scientists say they are particularly concerned that bats may be transmitting the sickness to each other, because bats of many species hibernate in the same place before dispersing to their maternity roosts in the spring. From there, they could travel 200 or more miles for the summer, potentially spreading the disease further.
Massachusetts doesn't have large numbers of wintering bats, but the majority of them live in the Chester mines. One mine has more than 7,000 bats, and the other about 900.
Last week, homeowners near the mines contacted the US Fish and Wildlife Service to tell them of strange bat behavior. The service and French's office dispatched the team and found afflicted bats in two mines. Bats in a third mine nearby will probably be hit with the syndrome soon, Oettingen said, because bats travel between the mines.
MassWildlife officials visited two other mines in Rowe this week that do not appear to be affected.
Caving groups have pitched in to help scientists, agreeing to avoid caving until scientists figure out what is going on. Some are also entering caves with scientists to identify afflicted bats. When they enter the mines, scientists use respirators and dress in plastic suits that are decontaminated afterward to ensure they are not carrying white nose syndrome with them.
Scientists are asking the public to contact state environmental officials if they see bats behaving strangely, such as flying in the daytime.
"We are not getting close to an answer," said von Oettingen. "We just have more questions."
Beth Daley can be reached by email at email@example.com.