CONCORD, N.H. — White nose syndrome continues to devastate New Hampshire’s bat population, even as other states report signs of recovery.
Biologists surveying caves and mines where bats spend the winter found only 28 bats, dashing hopes that this year might mark a turning point after several years of serious decline caused by white nose syndrome. The disease has killed millions of bats across the Northeast, and several species in New Hampshire have declined by nearly 99 percent.
“From our standpoint, it looks terrible,” said state Fish and Game biologist Emily Preston. “I am pretty depressed about this, because bats are a really important part of our ecology. With them missing and no longer feeding throughout our woodlands and along our streams, we don’t actually know what the effect will be.”
White nose syndrome is caused by a fungus that prompts bats to wake from their winter hibernation and die when they fly into the frigid, insect-less winter landscape. It was detected in New York in 2006 and since then has been spreading across North America killing at least a million bats.
One New Hampshire location that had 982 bats in 2009 had 281 a year later. The latest survey, conducted last month, included a search of three locations: One mine was empty, and 27 of the 28 bats found were in the third spot, Preston said. All but five were big brown bats, while two formerly very common species — little brown bats and northern long-eared bats — were missing.
That doesn’t mean the bats are gone from the state, however, since New Hampshire’s summer bats often fly to Vermont and New York for the winter.
“We do have some summer colonies we monitor, and they are still reproducing,” Preston said. “What I’m hoping, and what everyone else I know is hoping, is that the individuals that are surviving to reproduce are passing on whatever it is that is allowing them to reproduce.”
A biologist with Vermont’s Department of Fish and Wildlife said last month that he believes the worst of the epidemic in his state has passed, and that at least one affected species is starting to recover. Scott Darling said thousands of little brown bats continue to pass the winter in a cave in Dorset, Vt., though it’s unclear whether they have survived exposure to white nose or whether they are uninfected bats that could still face exposure.
Jeremy Coleman, the white nose coordinator for the U.S. Fish and Wildlife Service, says biologists in New York have seen similar changes, but questions remain about the long-term recovery of the species.
Beyond their insect-eating value, Preston said she is concerned about the bats’ fate simply because “bats are so cool.”
“This little mammal, with these incredibly versatile and strong and acrobatic wings — they live for 20 years. They’re not little flying mice, they’re totally different,” she said. “They’re amazing animals, so it’s very sad.”