THUNDER BAY — Mosquitoes are tormenting campers and anyone working or hiking in the bush these days.
It happens every year, but some years are worse than others, and this happens to be one of them.
The Thunder Bay District Health Unit sets traps for mosquitoes as part of its annual surveillance program for the West Nile virus.
Last week, 3,000 of the insects were caught in traps, double the number that were trapped a year ago at the same time.
Entomologist Ken Deacon coordinates TBDHU's vector-borne disease program.
He says weather conditions can cause mosquito populations to fluctuate widely from year to year.
"The mosquitoes do better, overall, when there's a cool, wet spring," Deacon said, "primarily if it's wet."
"They lay their eggs the previous summer in a depression. When the eggs get flooded, they hatch. The mosquitoes are in a safe habitat, they develop quickly, and they come out."
Deacon explained that there was lots of snow this winter, so any depression that wasn't filled in previous years would have been filled in the spring melt, allowing more eggs to hatch.
What's bad news for humans is good news for numerous predators that feast on the insects.
These include dragonflies, damsel flies, birds, bats and painted turtles, among others.
"The dragonflies really love mosquitoes, including during the larval stage which is aquatic. They eat mosquitoes by the bucketload. And the adults are great....they'll go into swarms and take out the mosquitoes," Deacon said.
He added that minnows also enjoy feasting on mosquitoes, and advised that anyone who has a pond in their yard would benefit by stocking it with minnows.
For personal protection against the insects, Deacon wears a bug shirt, available at outdoor stores.
The shirts are woven tightly and have components that make them mosquito-proof, he said, while still allowing for good air flow.
