CONCORD, N.H. — Are you planning to remove bats from your property? Be aware that a new rule designed to protect bats prohibits the exclusion of bats from unoccupied structures by licensed Wildlife Control Operators from May 15 through August 15, unless the N.H. Department of Health and Human Services has documented a rabid bat on the property. The rule was established this year in response to growing concern for the status of many of New Hampshire's bat populations, which have been decimated by white-nose syndrome (WNS) in recent years.
Bats in New Hampshire have suffered greatly as a result of white-nose syndrome. Populations of five of the state’s eight species of bats have plummeted, with hibernating numbers of the once-common little brown bat plunging over 99%, according to Emily Brunkhurst, a biologist with the New Hampshire Fish and Game Department's Nongame and Endangered Wildlife Program.
"This rule helps protect our remaining bat populations during the time when they are raising young," said Brunkhurst. "While this measure is certainly helpful, we strongly urge people to avoid evicting bats from any structure, occupied or otherwise, during the summer months. Our bats are in big trouble, and, this is something concrete you can do to help them survive."
WNS was recently found for the first time in Rockingham County, bringing the total number of New Hampshire counties where the deadly bat disease has been found to four.
"It was very sad to see bats with white muzzles this winter in a new county. So far we only know the fungus is on the bats, but not if they are severely infected. We had no dead bats to test, which is good. We will continue to monitor these hibernating bat colonies to see how they do," said Brunkhurst.
There are indications that some bats are surviving several years of exposure to WNS. Bats in a maternity colony in Fort Drum, N.Y., have returned to breed for at least three years in a row. There are also a small number of bats still hibernating in three of the New York caves where WNS was first found. A new banding effort this year may provide some insight into whether the returning bats are the same individuals.
In New Hampshire, biologists are continuing to investigate some World War II bunkers where bats hibernate, to see if these may be serving as refuges from the fungus. In March 2011, biologists banded several bats there and tested them for the fungus. Unfortunately, five bats did test positive for the fungus, and yet they looked healthy. This year, nine banded bats returned to the bunkers, including three northern long-eared bats, one of the species hardest hit by WNS.
"Two of the returning bats had previously tested positive for the fungus, so it was encouraging to know they had survived," said Brunkhurst. "In March, we again tested big brown and long-eared bats for the fungus, and banded those we could reach. Sadly, three new bats showed visible fungus, and we will not be able to track them over time, as they were up on a high ceiling and could not be captured for banding. Perhaps this year's early spring helped them survive, as they could get food earlier than usual."
So far, there has been no success with finding a treatment for WNS, and the disease continues to appear in new bat colonies across the country every winter; it has spread from the Northeast through the Midwest and arrived in states in the Deep South and west of the Mississippi River this year.
"Summer surveys are echoing what winter ones have shown us, that there are few bats left in the skies over New York, Vermont, Massachusetts and New Hampshire," said Brunkhurst. "But there are ways that you can help. If you have a bat colony, please allow it to remain. If you need to remove it, please do not do so until after the bat pups are ready to fly off. They need the roost for a week or so after they learn to fly, for protection during the day. By mid-August, they will have left with their mothers to fatten up and seek winter shelter. Then you can plug up those access holes."
To learn more about New Hampshire's bats, white-nose syndrome, and how you can help, visit http://www.wildnh.com/Wildlife/Nongame/bats.html.