Winnipeg to review mosquito control

Winnipeg's mosquito-control policy is going under a comprehensive review, after a city council approved a motion Wednesday to examine its methods of combating the bloodsucking insects.
Winnipeg's mosquito-control program, including the controversial no-spray buffer zones, could soon be under review. ((Associated Press))
Winnipeg's mosquito-control policy is going to get a comprehensive review.

City council approved a motion Wednesday by a vote of 13-1 to examine the methods Winnipeg uses to combat the bloodsucking insects.

The motion had earlier in the morning been discussed and recommended by the city's executive policy committee.

City administration has been directed to conduct the review immediately and report back at the next council meeting, in about a month.

Several councillors said they have besieged by calls from citizens complaining about the worst mosquito season in years.

"Winnipeggers look forward to enjoying our wonderful summers, and we need to do our part to ensure everyone can enjoy them," said Mayor Sam Katz.

"With the severe rainfalls combined with the heat we've experienced, we've seen a steady rise in mosquito populations that are directly affecting the quality of life and potentially, the health of our citizens.

"We need to take a comprehensive review of our policy to ensure we are taking a balanced yet effective and progressive approach to mosquito control."

Among the things the review will consider is reducing the size of the controversial no-spray buffer zones, or scrapping them altogether.

Mosquitoes caught in city traps are studied in a lab to determine the presence of Culex tarsalis, which is the type that can carry and transmit the West Nile virus. ((CBC))
It will also look into the possibility of not spraying the insecticide malathion, but finding a more environmentally friendly product.

Trucks equipped with fogging machines spray malathion as they drive through the streets and lanes throughout Winnipeg. The chemical has been approved for such use by Health Canada, but the practice has sparked controversy.

Malathion is an insecticide that has been registered for use in Canada since the 1950s.

Health Canada's Pest Management Regulatory Agency says the insecticide is toxic to all insects, including those, like honeybees, considered beneficial to humans. It is considered highly toxic to fish and other aquatic animals.

However, the agency says the insecticide "displays low toxicity" to birds, butterflies and mammals and has determined it is acceptable for use in controlling adult mosquitoes.

Opponents to malathion say the chemical can weaken the immune system and cause cancer, birth defects, intestinal disorders, kidney problems and other health problems.

Coun. Scott Fielding suggested that residents who don't want to experience the fogging should stay inside.

"Ensuring that people are staying inside when the malathion is being sprayed probably makes more sense as opposed to these buffer zones," he said.

No-spray zone

Winnipeg residents can ask to have their properties put on a no-spray list, meaning city crews will turn off the malathion fogging machine in a 100-metre zone around their land.

A City of Winnipeg truck fogs a street with malathion. ((CBC))
But in the context of an actual city block, a 100-metre buffer zone "can mean a non-application area of as many as 32 to 40 houses," Coun. Gord Steeves stated in a motion requesting the review of the city's control methods.

As part of the review, administrators will also look into what methods are used by other Canadian cities and whether any use buffer zones.

According to Todd Hanson, who is in charge of mosquito control just across the U.S. border in Grand Forks, N.D., that city uses permethrin — a biological adulticide that is safer for workers than the malathion Winnipeg uses.

"I guess what I shake my head at is that the synthetic pyrethroids aren't registered to be used in Winnipeg," he said.

Grand Forks residents can also apply for a buffer zone, but no one has yet this year, Hanson said.

"And once we start getting into the elevated risk of West Nile virus, when we start seeing the Culex tarsalis [the mosquito type that carries West Nile], that option no longer exists," he added.

Provincial approval required

When it comes to changing the buffer zones, the city must get provincial approval.

The permit to fog is issued by the province and one of the conditions is that the city obeys all buffer zones. The review by city administrators will tell councillors what the province has jurisdiction over and what the city controls.

Provincial Conservation Minister Bill Blaikie said he welcomes the city's review on the buffer zone policy.

"It is a policy that's been in place, I think, since 1982 and it's a policy that causes dissention within neighbourhoods and within the city every year. So, if there's a way to come up with a better policy, we're certainly open to being part of the solution on that," he said. 

Trap counts

The review will also look at whether the trap count required to begin fogging should be reduced.

Currently, in order for fogging to be started, two things must occur.

First, in at least one of the four quadrants of the city where traps are set, there must be at least 100 female adult mosquitoes caught (females are the ones that bite). And second, the average trap count throughout the city must be 25 female mosquitoes for three consecutive nights.

More than 1,000 mosquitoes have been recently found in some traps while the city-wide average is close to 400.

Fogging in Winnipeg began Saturday.