DORSET - The Mount Aeolus Cave is quite the hang out, for bats that is. The largest hibernaculum in New England, this is not just where many bats hibernate over the winter, but also one of the locations where white nose syndrome has devastated the bat population.

To try and understand this fungal infection killing off scores of bats, Alyssa Bennett with the department of Fish and Wildlife is using technology to help track these bats.

"We've never used this sort of technology before in Vermont," she said. "White nose syndrome most likely spread from a hibernaculum, a cave, in eastern New York," she said.

First discovered in 2008 in this cave, white nose syndrome killed off about 90 percent of the wintering bats that year. Bennett said while the data is still in the early stages and has not yet been completely analyzed, there are not as many bats dying.

"I think it's hopeful," she said. "Compared to the 90 percent decline, the good news is we aren't seeing that."

Bennett and others caught about 400 bats and glued small microchips to their backs. These chips, similar to the ones embedded in dogs or cats, don't have a power source but turn on when the bats fly through a series of loops, placed near the exit of the cave, she said. This tells the biologists when the bats woke up, letting them know if they're infected with white nose syndrome or not. The data from this experiment was collected last week. The cave is located on land owned by the Vermont chapter of The Nature Conservancy.


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Rose Paul, director of critical lands and conservation science, said they are not sure how white nose syndrome reached this particular cave, but that it was most likely spread from bat to bat.

Paul said that bats can live to be 30 years old and only have one or two pups a year. They are not a species that reproduces quickly and can replenish a population after a disease like white nose syndrome.

The research and data that is currently being reviewed was not just looking at when the bats woke up and if they were infected with white nose syndrome. There were two questions the biologists are trying to answer, Bennett said.

"What (percentage of the) population of the bats that stays to mate there in the winter, and two, we're trying to understand and get a handle on what the winter mortality rate is," she said.

From there, Bennett said they are trying to see if the bats are male or female and if they are reproductive. This will help them find out if the disease is having any larger effect, she said.

While bats or one cave may not seem important in the grand scheme of things, Paul said they are a crucial part of the ecosystem. About 10 years ago, there were issues with people entering the cave in winter, so a gate was put in place by the Nature Conservancy and the Vermont Department of Fish and Wildlife.

"Every time someone walks in the temperature rises and the noise...it can raise the bats out of hibernation," she said. "Each time they get roused out of hibernation, they have to bring their body temperature and metabolism back to normal and they deplete their fat resources. They may not have enough to make it through the winter."

The cave is surrounded by 200 acres, also owned and protected by the Nature Conservancy. Paul said this area is important because this is where the bats will eat during the summer months, as well as where they will mate before they hibernate in the cave during the winter.

Bennett said that bats are the primary forager of nighttime insects.

"Bats eat pests to people and to agriculture," she said. "Bats are also responsible for eating forests pests that munch on trees."

Some of the head waters of Otter Creek and wetlands along Route 7A offer an area the bats enjoy feeding, Paul said. The woodlands on private property, as well as the protected land, offer safe haven for the healthy bats. Before they hibernate, the bats come to this area to mate and will roost during the day in the cave, as well as trees in the area.

"All landowners are playing a role in providing a good bat habitat," she said. "I'm grateful to all those landowners whose land is contributing to the health of our bats."