With bats struggling to survive in Vermont, local action is being taken to limit pesticides that may harm wildlife, and experts on endangered species are urging the state government to act, too.
On Feb. 26, the Vermont Endangered Species Committee advised Julie Moore, secretary of the Agency of Natural Resources, to require permits for spraying pesticides that may harm bats. The advisory group — made up of experts on flora, fauna and agriculture — found that the pesticides in question could harm endangered bats in Vermont.
The pesticides are used to control mosquitos.
Moore has not issued a decision yet, but the Department of Fish and Wildlife has pushed against the recommendation and the report that informed it. The department’s commissioner, lawyers and staff biologists say there isn’t enough evidence to prove that the pesticides harm bats.
State officials expect a decision before pesticide spraying begins this spring.
Regardless of state policy, one town has already decided to opt out of spraying this spring.
On Town Meeting Day, Salisbury voted to defund the BLSG Insect Control District that sprays pesticides — specifically, malathion and permethrin — to kill mosquitos in member towns: Brandon, Leicester, Salisbury, Goshen and Pittsford. The abbreviation BLSG comes from the names of four of the towns.
Residents said their vote reflects growing concerns about the impact of pesticides on both human and environmental health, and dissatisfaction about how the insect control district has been spending the towns’ money.
No one is entirely sure what will happen now that Salisbury has decided not to pay for pesticides.
“Our thinking is if we don’t pay them any money, then we won’t get sprayed,” said Jim Andrews, a Salisbury resident. Andrews is a herpetologist and author of the Vermont Reptile and Amphibian Atlas. For Andrews and others in town who oppose the use of pesticides, that would be a good outcome.
“A big cheer went up from many of us,” he said. “A lot of people would rather not use these chemicals.”
Jeff Schumann, president of the Lake Dunmore Fern Lake Association and Salisbury’s representative to the BLSG, said what comes next is uncharted territory.
“The lake association is concerned with the mosquitos,” said Schumann, who voted to stay in the district for another year.
Disagreements over state policy
As bat populations plummeted during the white-nose syndrome die-off, a coalition of local and regional groups got involved — including Moosalamoo Woods and Waters, Vermont Natural Resources Council, the Center for Biological Diversity, Biodiversity Research Institute, the National Wildlife Federation, Colrain Center for Conservation and Wildlife, and Vermont Law School’s Environmental Advocacy Clinic.
In August 2019, they presented a detailed report to the state, prepared by the Arrowwood Environmental consulting firm.
The report found it was highly likely that the pesticides being sprayed by insect control districts were harming bats and resulting in a “take” — or the killing of a bat. That’s a violation of state law since the bats are endangered, according to Mason Overstreet, a staff attorney at Vermont Law School’s Environmental Advocacy Clinic.
The coalition’s board voted 6-0 in favor of the recommendation, with two members not voting and one abstention.
Vermont’s Endangered Species Committee agreed with the report’s findings that pesticides could pose a significant risk to bats. The committee advises the secretary of the Agency of Natural Resources on all matters relating to endangered and threatened species, including how to protect the species. The committee includes the secretary of Agriculture, Food and Markets; the commissioner of Fish and Wildlife; the commissioner of Forests, Parks and Recreation; and six members from the fields of forestry, agriculture, wildlife and botany.
But the Vermont Department of Fish and Wildlife disagrees with the recommendation that additional permits are needed to protect the bats, said Commissioner Louis Porter.
“In our view, in the view of our scientists and attorneys, we did not believe that there is a demonstrated likelihood of harm or death to bats,” Porter said.
Fish and Wildlife biologist Alyssa Bennett agreed: “I was not able to find enough information to say there is a likelihood that ‘take’ is occurring.”
Bennett said bats tend to avoid fog and mist because it prevents them from echolocating.
“We don’t have field observations to say whether bats are flying through this flume,” she said.
A law of prevention
But Mason Overstreet, the Vermont Law School attorney, said Vermont’s endangered species law is designed to prevent injury to bats, whether or not that injury has already occurred.
“Vermont’s endangered law is unique because of how broad it is,” Overstreet said. The law covers acts that create “a risk of injury to wildlife, whether or not the injury occurs,” Overstreet said.
“Here you have an expert report that now has been vetted by Vermont’s most acclaimed scientists that these pesticides do in fact create enough of a risk to meet that bar, and thus the state needs to require a permit,” Overstreet said.
According to Bill Kilpatrick, there is consensus among scientists that the pesticides could harm bats. Kilpatrick, a biologist, chairs a scientific advisory group that reports to the Vermont Endangered Species Committee.
The disagreement is about how likely it is that harm is actually occurring.
Kilpatrick said the pesticides could be absorbed through the bats’ wings. The bats could get coated with the insecticide before flying back to their roost, where the chemicals could be ingested during communal grooming.
“A big area is being covered with this mist of adulticides that potentially are impacting these bat species,” Kilpatrick said. The area in question is about 4,000 acres, according to Kilpatrick.
Jim Andrews, the Salisbury resident and herpetologist, said the Agency of Natural Resources secretary usually follows recommendations made by the Endangered Species Committee. Andrews also chairs the reptile and amphibian special advisory group to the Endangered Species Committee.
He said the Fish and Wildlife Department’s opposition to the recommendation is noteworthy.
“We rarely see them put on such a dog-and-pony show to resist the recommendation,” Andrews said. He said the department “lined up their employees to argue against this.”
The incidental “take” permit would not prevent BLSG from spraying pesticides, but it would require it to gather additional information.
Whether the Agency of Natural Resources decides to require permits is up to Secretary Moore. According to Porter, he and Moore will meet to discuss the Endangered Species Committee recommendation before a decision is made.
Beleaguered populations
The BLSG is one of only two insect control districts in a part of the state that is infamous for its mosquitos. Former governor Madeleine Kunin’s run-in with those mosquitos has become lore among locals. As Chris Fastie tells it, the mosquitos were so bad when Gov. Kunin came to visit in 1989 that they sent her running for cover in her helicopter.
“It became national news,” he said. Fastie is president of Moosalamoo Woods and Waters, an environmental organization that joined the coalition to push for tighter state control around pesticide use to protect endangered bats.
Residents agree that recent years haven’t been so bad for bugs. And locals are also aware that they share the area with bats, especially when bats started dying off because of white-nose syndrome.
“We’re concerned about this beleaguered population,” Fastie said. “It was just several years ago that we started to put two and two together and realize that what BLSG is doing is obviously a risk to these bats.”
The insect control district sprays pesticide at night during the summer — a time when bats are active, flying around and foraging for food. BLSG operators drive along the roads in central Vermont, releasing a mist of pesticides that hang in the air for as long as an hour or two.
“These roads that BLSG is driving down are rural roads, some incredibly rural roads going through what is arguably the best bat-feeding habitat of Vermont,” Fastie said.
All five of Vermont’s endangered and threatened bat species are known to live in this part of the state, including the little brown bat, whose Vermont population has dropped by 90% as a result of white-nose syndrome.
While the little brown bat’s population is now stable, other populations are still declining, such as the tricolored and Indiana bat. Their numbers are now so low that it’s hard to even detect the rate of decline, according to Alyssa Bennett the Fish and Wildlife biologist.
The northern long-eared bat is another species that seems to be on the edge. “We rarely find them underground anymore,” Bennett said.
Effective alternatives are available
The Lemon Fair Insect Control District, adjacent to BLSG, covers the neighboring towns of Bridport, Cornwall and Weybridge. But Lemon Fair has taken a different approach to mosquito control — one that scientists think might be more friendly to bats.
Lemon Fair uses larvicide to target mosquito larva instead of adulticide that kills adult mosquitoes; the larvicide does not affect bats. Larvicide doesn’t affect bats, but the plumes of adulticide sprayed in the air at night when bats are flying and foraging could harm a species that is already struggling.
Some environmentalists argue that larvicide is a better, more modern approach to mosquito control.
“It is clear that the (BLSG) district is still utilizing the crude, blunt, 1950s technology of adulticide spraying, instead of the more modern, 21st-century technology emphasizing the targeted application of larvicide,” wrote endangered species legal scholars Patrick Parenteau and Zygmunt Plater in a letter to Allan Strong, chair of the Endangered Species Committee.
Still, even larvicide may not be a perfect solution. Herpetologist Jim Andrews said he has some concerns about how larvicide impacts aquatic creatures and questions if the spraying program is the right thing to do.
“It’s been in place for a long time without adequate review, in my opinion,” he said.
