Early mosquito season expected
Use of controversial insecticide draws council questions
While city mosquito control experts warned Edmonton residents to expect the critters to arrive early this season, several council members have questions about the city’s treatment techniques.
City crews started spraying last week and are now using both the controversial insecticide Dursban 2.5 and the biological alternative VectoBac. They expect the first wave of adult mosquitoes at the end of April.
Edmonton is the last Canadian municipality to use Dursban, a neurotoxin and restricted insecticide, and a recent investigation by the volunteer group Pesticide Free Alberta revealed it’s being used within city limits, 30 metres from homes and in natural areas such as Terwilligar Park.
“My understanding was that it was only being used in non-populated areas on the edge of the city, well away from populations,” Mayor Don Iveson said Monday. “Recent reports that’s its been used closer to people does give me concern and I will have questions for administration ... My understanding is it shouldn’t be used near populations and I wouldn’t want it near my kids.”
Coun. Mike Nickel said Edmonton should drop Dursban. “This insecticide is the one that also kills bees,” he said. “It’s pretty hard for the Communities in Bloom and the beekeeping advocate to argue that we should be keeping this insecticide.”
Dow Agrosciences stopped making Dursban, but after buying Winnipeg’s remaining supply, Edmonton has enough to last into next spring, said city biologist Mike Jenkins. The city uses the chemical because spring here is usually too cold for VectoBac to be effective, he said. If city crews stops using it, he expects Edmontonians will see more mosquitoes.
By way of comparison, technicians currently catch a third as many mosquitoes in light traps inside the city compared to outside the mosquito control area, he said.
Warm temperatures gave the insects a head start, Jenkins said. The pest management team is already finding larvae growing in wet areas. Depending on weather, it should take two to three weeks for those early generations to emerge. Any large, slow mosquitoes already bothering Edmontonians overwintered here as adults under the snow. “The good news is there wasn’t a lot of snow on the ground,” he said. Much of that snow melt has been already absorbed into the ground, reducing the habitat for mosquitoes, he said.