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- A mosquito
Getting your summer cardio from swatting and scratching? You’re not alone. Vermont has twice as many mosquitoes this year as compared to the average during the past 13 years.
A hot, wet summer has created the perfect environment for everyone’s least-favorite pests, who are reveling in all this water, according to Patti Casey, environmental surveillance program manager for the Vermont Agency of Agriculture, Food and Markets.
Even before the historic flooding last month, Vermont already had more mosquitoes this season, which typically lasts from April to October. But the rainfall and flooding certainly didn’t help; water in standing pools on saturated ground is taking a long time to evaporate and meanwhile provides ideal breeding sites, Casey said. Trash piles have accumulated, and the water that collects in little crevices also provides havens for mosquitoes, which only need a small amount of water to lay their eggs.
State employees collect mosquitoes at least once weekly from June to October at 105 trapping sites. The specimens are brought to a lab at the Vermont State University Randolph Campus, where they are tested for mosquito-borne illnesses. So far this season, testing has not found West Nile virus or eastern equine encephalitis, both of which can be fatal.
A warming climate could mean Vermont is facing a mosquito-filled future. Not only does it increase the amount of mosquitoes but also the number of species. Five years ago, the state detected the Asian tiger mosquito, which is typically found in southern states, for the first time.
Vermont only engages in mosquito control when the health department determines that there is a significant risk to public health from mosquito-borne diseases such as eastern equine encephalitis. That last happened in 2013, Casey said.
Some towns have mosquito-control districts. The Otter Creek Watershed Insect Control District was created in 1978 and is made up of six towns in Addison and Rutland counties, while the Lemon Fair Insect Control District, three towns in Addison County, was founded in 2006. Both receive some funding from the state. The districts use a bacterium to kill larvae.
This year was the first that Otter Creek received a permit to use adulticide, which is a chemical applied by sprayers mounted on trucks. All of the chemicals are approved by the U.S. Environmental Protection Agency and vetted by the Vermont Pesticide Advisory Council, though they have proven controversial.
The agencies also advise residents to eliminate standing water on their own properties, including by unclogging gutters, according to Craig Zondag, a field biologist for Lemon Fair. Anything from a kiddie pool to a boot tray left in the rain can become a mosquito habitat.
Individuals do not need a license to treat their own property. They can buy Mosquito Dunks or Mosquito Bits at their local hardware store; the larvicides have the same active ingredient the mosquito control districts use. “If I had a pond, I would absolutely treat it for mosquito larvae,” Casey said.
While mosquitoes are reviled, they are a food source for bats and other small critters, such as dragonfly larvae and tadpoles. Male mosquitoes are also pollinators that feed on nectar instead of biting people and birds, Casey said.
Humans can protect themselves from the insects. Dawn and dusk tend to be the busiest mosquito times, though the flood created a big patch of “day biters,” Casey said.
She advised people to wear long sleeves and long pants and use whatever repellent they feel comfortable with. Casey uses DEET for a Vermont hike and treats her fieldwork clothes with permethrin, which can be effective against mosquitoes and ticks.
“Nothing is going to keep me from going outdoors and enjoying Vermont,” she said. “So it’s just a matter of doing what we have to do to protect ourselves to be able to be outdoors.”