Cranbrook mosquito control on the larvae attack

City encouraging home and property owners curb mosquito development by removing sources of standing water from around the home.

Mosquito season is upon us in many places and right around the corner in others, so it’s a good time to find out what Cranbrook is doing in preparation.

The municipality contracts out the job to Morrow BioScience Ltd, a company out of North Vancouver that specializes in mosquito control. Locally, Kendra Lewis is area co-ordinator and technician of the Cranbrook leg of the program.

Lewis said around this time, the biggest thing residents can do to reduce mosquito activity, is clean up yards and gutters. The downpours of late provide the perfect breeding grounds for mosquitos.

Lewis said things like wheelbarrows, water barrels, water dishes that pets aren’t using and ponds that don’t have fish in them are prime places for mosquitos to proliferate.

“Anything that holds water, that’s what people should be looking at in their own yards,” Lewis said, adding that all of the big sites around Cranbrook have been treated a few times now.

“Our sites are clear, it’s just stuff within the city that we need people to work on right now,” she said. “It’s definitely been a bad mosquito year, but we’ve kept on top of it, that’s for sure.”

Lewis said she has killed a lot of larvae already this season, and attributes the high numbers to last year’s high water as well. She noted a lot of egg-laying went on and all of her permanent sites, sometimes seeing 200 larvae per sample dip.

She said they do a lot of work around the community forest, Idle Wild, Echo Fields and at the breakaways around Elizabeth Lake, though not the lake itself.

“We don’t treat Elizabeth Lake, because we don’t have a problem with it,” she said.

“Everywhere that I treated this year has lots (of larvae),” she said.

Mosquito eggs can lay dormant for up to seven years, she said, so with the water fluctuating like it has been, they have done multiple treatments.

Mosquitoes go through four stages of development: egg, larvae, pupa and adult. When eggs come into contact with water during the spring and summer months, they hatch into larvae. The larvae feed on plant material and develop into pupae, which later become adult mosquitoes. After mating, female mosquitoes search for blood to complete the egg development stage. Morrow BioScience Ltd. directs efforts at the larvae stage.

To kill they use a product called Aquabac 200G, a granular mosquito larvicide. It contains a naturally occurring bacterium Bacillus thuringiensis israelensis (Bti) which targets the larvae, but doesn’t harm birds, mammals, amphibians or other insects. The larvicide can be applied by hand, blower or helicopter.

The city also encouraged home and property owners curb mosquito development by removing sources of standing water from around the home. Some suggestions:

• Clogged gutters;

• Flower pot trays;

• Outside pet dishes;

• Kids’ pools, toys;

• Bird baths, feeders;

• Canoes/boats, tires