Treleven Farm has a Forest Management Plan which places the conservation of habitat for endangered bats as a top priority. In practice, this usually means opening the forest canopy in the vicinity of potential roost trees—primarily shagbark hickories—in ways that wildlife biologists believe will make them more attractive to the Indiana bat as well as other threatened bat species.
During the summer months, bats often roost in shagbark hickories during the daylight hours; females gather in colonies and raise their pups in these trees, too. At night, the bats leave their roosts to go foraging for insects. A mature bat can eat half its body weight every night—including untold numbers of mosquitoes as well as other insects whose populations, if left unchecked, would have deleterious effects upon ourselves and on the ecosystem.
Since the advent, during the winter of 2006-2007, of White-Nose Syndrome—a fungus that infests the skin of many bat species as they spend the winter hibernating—an estimated seven million bats in nineteen states and four Canadian provinces have died. The suddenness and severity with which this calamity has taken place makes it one of the worst wildlife health crises in recorded history. If bats are to turn the corner and start to rebuild their numbers, they will need plenty of high-quality habitat—and that is a resource that Treleven Farm can help with.
Because of the way in which this particular hickory tree’s bark exfoliates, creating dark and protected crevices, they offer prime daytime roosting for bats. Shagbark hickories grow very slowly, but they can live—and provide ideal bat habitat—for over two hundred years. At Treleven Farm there are approximately one hundred mature shagbark hickories, and about half of them have thus far been enhanced for the bats’ use by carefully directed thinning of the forest surrounding them. This work has taken place in four distinct “roost zones” covering about four acres of the woods on the farm. There are also two half-acre “foraging zones” where the forest has been altered so as to make it easier for bats to fly around in the dark and fill their stomachs.
On the night of June 14, 2012, biologists from Vermont’s Department of Fish and Wildlife were able to catch half a dozen bats in mist nets that were set up in the woods here. Vital information on each bat was recorded, and then they were released to go on about their business. One of these bats was of the species Myotis sodalis—the Indiana bat, which has been officially Endangered by the U.S. Fish and Wildlife Service since 1967. And she was a pregnant female! Subsequently, four more Indiana bats were found to be roosting in the same tree with her. And in all likelihood there are many more.
All of the bat zones at Treleven Farm are connected by well-marked footpaths that are easy to hike. Don Mitchell, who did most of this forestry work over the period 2010-2012, loves to show visitors where and how to examine the bat zones. Beginning in August of 2013, he’ll be conducting weekly tours of the habitat-enhanced forests every Saturday morning at 10 o’clock from August 3, 2013 through November 2, 2013. Just come to Don and Cheryl Mitchell’s house, dressed for an hour-long walk in the woods. Don’t expect to see bats, though—because if they’re here, they’ll be sleeping at that time of day. But do come prepared to consider our responsibilities, as humans, toward endangered species. And to think about how all of us are all in this together.
Don has written a book about the habitat-enhancement project, titled FLYING BLIND: One Man’s Adventures Battling Buckthorn, Making Peace with Authority, and Creating a Home for Endangered Bats. The book’s release by Chelsea Green Publishing is scheduled for September of this year.
Ethan Mitchell drew the attached map of Treleven Farm, showing the various bat zones in heavy dark lines as well as the trails that connect them.