[ccfic caption-text format="plaintext"]
By Douglas McCulloch
Hometown Weekly Staff
With spring underway, the Norfolk County Mosquito Control District is already busy preparing for the summer mosquito season.
From April 13 to April 15, the agency targeted over 8,400 acres of wetlands across Norfolk County with a granular larvicide applied by helicopter, with areas targeted in all of the towns in the agency’s coverage area.
Norfolk County Mosquito Control District Director Dave Lawson explained that a lot of planning and research goes into determining where to target the larvicide application. The agency utilizes computerized maps of wetland areas across the county and does water testing on areas that are thought to be prime locations for mosquito breeding.
“We have done surveillance on [the wetlands], we know they are mosquito habitats,” Lawson explained. “We go out in the wetlands and we sample the water to see if mosquito larvae are in the water.”
The larvicide used includes a key biological larvicide called bacillus thuringiensis israelensis (Bti). The larvicide is a naturally occurring organic microbe normally found in soil, and is used because it only targets mosquito larvae with very few non-target effects, according to the Norfolk County Mosquito Control District’s website.
Lawson said it is often difficult to predict how the mosquito season will be for a particular year, because it depends heavily on the weather leading up to summer.
“It’s always too early to say, how the mosquito season goes is dependent on how much rain you get on a week to week basis,” Lawson said.
He noted that if the region receives less rain than usual, mosquito season could be milder this year, but more rain means the mosquito season could be worse than usual.
The agency remains concerned about the threats of EEE and West Nile Virus.
