A vast percentage of land in East Gwillimbury is low-lying terrain that creates perfect mosquito breeding sites each spring.  Therefore, during the month of April, a non-chemical substance is applied to the main breeding sites of the Spring Aedes species of mosquitoes across East Gwillimbury. The breeding sites are wet larval habitats where mosquito larvae develop prior to becoming flying, biting adult mosquitoes.

Product used

The substance used is natural bacteria known as Bti. Bti biodegrades in the breeding sites within 48 hours. Bti is harmless to humans, pets and the environment. Bti is also known by its brand name Vectobac. Helicopters distribute the Vectobac onto the main breeding sites of the spring Aedes mosquito in the month of April. It is this species that causes the excessive biting problem from May to mid-July.

The main breeding sites of the Spring Aedes mosquito are pools which form as the snow melts in February through April. These pools, which create the Spring Aedes larval habitat, are commonly found in hardwood bush areas and areas with a lot of wet, leafy litter. The treatment occurs throughout the town unless residents specifically request not to be a part of the program. Anyone wishing to object to the mosquito control program must complete the online submission form.

Take the time to view the educational YouTube video entitled "Biological Larvicides: The Natural Solution" for additional information. © 2011 Valent BioSciences Corporation, used with permission. For further information please visit or read Health Canada's Bti Fact sheet.

Your own backyard

One tire, thrown away in a backyard will hold enough warm water in its rim to breed 100,000 mosquitoes during April. To ensure a truly effective program, early spring clean-up is necessary. Residents must participate by eliminating potential breeding sites in their yards through sanitation and maintenance. Clean or remove poorly maintained pools, wading pools, old tires, rain barrels, troughs and other similar containers that collect rainwater and create perfect breeding sites for mosquitoes.

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Reports submitted annually prove in scientific terms what most East Gwillimbury resident know already! The mosquito control program is highly successful. Biting activity is reduced 75%. The larvae population in treated ponds is reduced 100%.

Don't expect 100% elimination of mosquitoes as a result of our control program. There are several species of mosquitoes found in East Gwillimbury. The goal of this program is to reduce the biting activity to a tolerable level. Besides, if all the mosquitoes were destroyed, what would the bats and purple martins eat?

You may also wish to view the mosquito control program potential treatment areas map.