Feel free to copy/paste for your community newsletters!
Recently, city council passed several related motions to ensure our green spaces are healthy spaces for people and nature:
- easier process for creating community gardens
- permission to naturalize boulevards
- cosmetic pesticide ban beginning in 2023
- end to aerial spraying of wetlands with Bti
Here are some FAQs to help people understand this last motion.
Q: What does Bti stand for?
A: Bacillus thuringiensis israelensis. It is a biological control (a bacterium).
Q: Isn’t Bti safe for people?
A: There is no evidence to show that Bti poses a direct threat to human health, but evidence shows it does cause indirect harm by disrupting the ecosystem that we depend on, and ecosystem disruption and the climate crisis go hand-in-hand. As we are seeing with the floods, massive wildfires, and “heat domes” happening around the world, our health and safety are inextricably connected with environmental health. The World Health Organization and the United Nations now recognize that human and environmental health are one and the same and have undertaken a “One Health” approach to all their work.
Q: Doesn’t spraying mosquitos protect human health?
A: No. The best way to prevent against zoonotic diseases is to ensure a healthy ecosystem. Our current risk of West Nile Virus in Edmonton is low (we’ve had just one case, and that was in 2013); the mosquitoes sprayed here are simply “nuisance mosquitoes.” Even in Quebec, where the risk of West Nile Virus is higher, they stopped spraying Bti as no evidence exists to show that it worked to prevent infections. Edmonton’s own research has shown that an effective way to control mosquito populations is through naturalized wetlands that provide excellent habitat for dragonflies. Notably, the West Nile Virus “center” in Canada (Oakville, Ontario) does not have naturalized wetlands; instead, it is full of manicured lawns. The best way to protect against mosquito bites overall is through personal protective measures. Some countries are even implementing non-spray measures to deal with malaria.
Q: What are the main concerns with Bti?
A: Bti negatively affects ecosystems. By killing mosquito and other insect larvae (like chironomids), it basically destroys the base of the food chain – upon which all other species, including mosquito predators like dragonflies, frogs, birds, and bats, depend. Songbird populations have collapsed across North America (mostly as a result of spraying and habitat loss) and we need to be protecting them, not further stressing them. Research has also shown that Bti directly impacts frogs.
Beyond ecosystem impacts, Bti is very expensive. Edmonton has been spending over $1 million per year (and carbon emissions from helicopter spraying, when we are in a climate crisis) to spray Bti when dragonflies and songbirds do it for free.
Q: What are the best ways to protect my family and me from mosquito bites?
A:
- Reduce mosquito habitat: clean gutters, don’t leave out plastic toys, tires, garbage, etc. that can collect water, and keep ponds and water features healthy. Most mosquito bites come from insects that have hatched nearby.
- Protect and plant native trees and shrubs and fruit trees on your property to attract birds.
- Put out a bird bath to attract birds (make sure to change this water every day so that it does not become stagnant) and bird houses.
- Keep cats indoors so that they do not scare birds away.
- Plant natural mosquito repellent plants, such as organic citronella or lavender, in your yard and in pots on your deck. Do not use pesticides or foggers or any other products that will repel or harm birds or beneficial insects on your property.
- Switch to fragrance-free laundry and personal care products. Mosquitoes are attracted to perfume scents.
- Do not use bug zappers. They are counterproductive because mosquitoes are not attracted to light, but important pollinators such as moths are. Instead, set up a fan on your deck; mosquitoes do not like moving air.
- Keep screens in good condition.
- Drape fine mesh over attended cribs, playpens, and strollers.
- During periods when mosquitoes are a problem, wear light-coloured, loose-fitting clothes with long sleeves and long pants.
- Use any of the large selection of natural mosquito repellents on the market.
- Some additional good resources for reducing mosquito bites while supporting ecosystems:
- this resource from Quebec
- this article from David Suzuki’s Queen of Green
- tips on how to attract birds and bats into your green spaces
Links to further information:
This excellent Radio-Canada documentary on Bti. If you don’t speak French, turn on the English captioning.
Website for Pesticide Free Edmonton
A few links to scientific studies on Bti from scientists without ties to industry:
https://www.sciencedirect.com/science/article/abs/pii/S0147651318311862
https://www.sciencedirect.com/science/article/pii/S0048969720313127