esticides at all to just go right out there — just hand them a book to study without any interaction with anybody,” Alm said. “I don’t think that’s the way to go.”
Spraying for mosquitoes and ticks and dousing lands with pesticides and herbicides isn’t limited to private yards. From 2010 to 2016, the Rhode Island Department of Transportation applied at least 43,959 gallons of herbicide to public lands across the state.
Pesticides are also applied at state parks, to the Statehouse grounds, and on other state-managed lands. Each of Rhode Island’s 39 cities and towns also apply poisons to eliminate unwanted plants and insects from public property.
DEM does require that commercial applicators pass an examination, which is based on federal regulations regarding the types of pesticides they will be using.
Healey said the state agency does require testing to demonstrate practical knowledge in the specific areas as outlined in federal law. He noted that from Oct. 1, 2020 to Sept. 30 of this year DEM administered 465 exams, of which 50 were retakes. Of the 415 first-attempt exams, 294 passed and 121 failed, for a success rate of 71 percent.
To maintain state certification, DEM requires private applicators take six hours of recertification training every five years. Commercial applicators must take eight hours of recertification training every five years.
A “shortsighted fix”
Mosquito spraying usually takes place during business hours, in other words, in daylight, when pollinators are active and most mosquitoes are not flying, but resting.
Aimee Code, pesticide program director for the Portland, Ore.-based Xerces Society for Invertebrate Conservation, noted yard spraying often misses the intended targets and kills beneficial species.
“There are some mosquitoes that are out during the day, but definitely, the vast majority of the chemical that’s being sprayed in your yard is not touching the mosquito — it’s not doing what it was meant to do — it’s just contaminating your yard,” she said, “and it potentially could be killing any number of beneficial insects that are in your yard, including bees, butterflies, beneficial wasps, many insects that are actually eating and killing pests in your yard.”
The other shortcoming of the chemical approach is that mosquitoes are mobile, flying into yards that have been sprayed and replacing those insects that were killed.
“Just because you’re spraying your yard, mosquitoes can still move in after that chemical settles out and they’re going to still bother you,” Code said. “It’s a very short-term, shortsighted fix.”
The sales pitch for one of the more popular mosquito-spraying companies is “The only good mosquito is a dead one.” But what about the ecological roles mosquitoes play?
Raven Forrest Fruscalzo is a science communicator who earned a master’s of science degree with a focus on entomology from the University of Notre Dame. She also produces a podcast, Tiny Vampires, about blood-sucking invertebrates.
Fruscalzo said mosquitoes are valuable, filling more than one niche in the ecosystem.
“Because they’re so low on the food chain and they’re produced in such numbers, especially mosquito larvae, they’re one of the primary food sources of young dragon flies,” she said. “So, they’re an aquatic insect and a lot of other important aquatic insects are feeding on them. … They’re also pollinators, so they’re going after the nectar in plants, just like other pollinators.”
Fruscalzo also noted that not all mosquitoes feed on humans.
“There are a lot of different types of mosquitoes,” she said. “There are thousands of species and many of them, in fact, never bite humans. They’ll feed off of reptiles like snakes or amphibians, so they have different specializations. Lots of different things eat them. For example, if you put a hummingbird feeder out, you’ll reduce the number of mosquitoes in your yard because hummingbirds love eating mosquitoes.”
DEM recommends an integrated management approach to controlling mosquitoes. This approach includes eliminating standing water where they breed, repairing window scr