Indiana bats have found a home in a cave about 3,000 feet from one of five wind turbines proposed for Mount Equinox, and that’s close enough to cause concern, said Scott Darling, a biologist with the state Agency of Natural Resources.
Obtaining a federal Fish and Wildlife permit for construction deemed likely to interfere with their habitat is no simple thing, and could take as long as two or three years, he said.
The problem is compounded because there is extremely little reliable scientific data on how wind farms affect bat behavior, he said Tuesday.
"We’re very early in understanding the conflicts between bats and wind farms," he said. "The U.S. Fish and Wildlife permit is not easily achieved — we’ll have to provide enough information on the level of threat to the Indiana bat."
The Equinox project is unique among wind farms in Vermont because it is the only one proposed to be sited that close to a bat habitat, a problem compounded by the bats’ endangered species status, he said.
But Harley Lee, president of Endless Energy Corp. of Yarmouth, Maine, the developer of the proposed five-turbine Equinox wind farm, said the situation should not be a showstopper.
Endless Energy does not need that permit in hand before anticipated construction next summer, Lee said. By that time, he hopes to obtain approval from the state Public Service Board for the project, he said.
However, Lee’s firm intended to develop a habitat conservation plan to mitigate harmful effects on the bat population that could be linked to the wind farm, he said.
"We’ll work with the regulators to monitor the impacts and make adjustments," he said. "It’s an unpredictable process, and it’s dealing with the federal bureaucracy, so it may take time."
The issue of the endangered bats dominated a meeting of the Manchester Planning Commission Monday night, which held the second in a series of four public forums on the proposed wind project.
Research on the effect wind turbine blades have on bats is still preliminary, but enough results are in to raise red flags, according to information presented by Darling and Forrest Hammond, a district wildlife biologist with the Agency of Natural Resources.
"Wind farms are fairly new to us," Hammond said. "We have to look at the rest of the country to see what has happened and the conflicts with wildlife."
At wind farms in Pennsylvania and West Virginia, studies conducted during 2004 showed an unusually high level of bat fatalities — more than 700 bats from seven different species were killed during a six-week period that summer, the biologists said.
But results varied at different wind farms and no conclusive findings have yet been drawn by the scientific community, Darling said.
Wind farms will kill bats, although scientists did not know why. Most of the deaths seemed to occur during periods when the winds were not blowing strongly, he said.
The question is what is an acceptable number of deaths that can be tied to a wind farm, he said.
Scott Reynolds, a bat consultant hired by Endless Energy to analyze the effect of the wind farm on the local population, estimated that 200 bats might be killed annually by the turbines. But the region around Equinox is a rich bat habitat, and that was not a large enough number to threaten the survival of bats in general, he said.
A related question is whether a disproportionately high number may be the nearby and endangered Indiana bat, he said.
Other experts presented data at the meeting on the dangers posed to migratory birds and rare and unusual plants and vegetation, but those threats were deemed relatively minor.
With so little firm data to go on, at some point the state will need to make its best determination on the basis of the information available, said Lee Krohn, Manchester’s planning director.
While the issue with the bats is significant, it also needed to be looked at from a big-picture standpoint, he said.
"We need to consider how many bats will be killed by the turbines, but we also need to consider how many are being killed by other environmental impacts," he said. "We’re killing trees all over Vermont because of fossil fuel consumption in the Midwest."
Contact Andrew McKeever at firstname.lastname@example.org
This article is the work of the source indicated. Any opinions expressed in it are not necessarily those of National Wind Watch.