With last weekend’s historic rainfall now more than a week into the rearview mirror and Assiniboine River levels continuing to slowly recede, the clock may now be ticking on what could potentially be a significant uptick in the population of the region’s most notorious summer pest in the not-too-distant future.
Such is the life cycle of the mosquito, which thrives in available stagnant water as part of the process of laying eggs that ultimately lead to higher numbers.
According to Dave Lane, Branch Manager of Brandon’s Poulin’s Pest Control, one could expect to see a significant rise in mosquitos in a region about 14 days after a major rain event, accounting for initial days of faster water run-off before excess water rests as the kind of standing water that the pests thrive in.
As if the effects of an historic rainfall on regular in-season breeding aren’t enough, there’s potential for the problem to be compounded this year given that mosquito eggs can last for years in the soil, that they tend to lay eggs in flood-prone zones and the area saw a minimal amount of spring runoff in 2020 that would have otherwise led to Spring mosquitos. With those eggs now potentially covered in water, conditions would be favourable for their development to progress as well.
Areas of standing water like these can currently be found throughout the city following last week’s rains
The City of Brandon maintains weekly trap counts based on traps throughout the city as a way of assessing the presence of mosquitos, ultimately arriving at a value known as the Adulticiding Factor Analysis (AFA) value in rating severity. Thus far in 2020, weekly trap counts have resulted in an AFA value of ‘Low’ since weekly counts began in late May.
The City is expected to release its weekly trap counts on Tuesday with data based on Saturday and Sunday. It’s likely that counts will not yet be into meaningful territory at that time. Under Lane’s scenario one could surmise it’s more likely that trap counts would register notably higher on the AFA scale the following week.
The City has what could be described as a policy that uses fogging for nuisance mosquitos as a last resort, leaning heavily on larviciding of standing pools of water in Brandon and area in attempt to proactively stay ahead increases in population of the pest. June 28’s record-breaking 155mm of rain and subsequent storms during the week have made the city and area a sort of “land of 10,000 lakes” that is likely to prove challenging to larviciding efforts.
Decisions on fogging are made based on any given week’s AFA value, with action only taken if consecutive weeks register in the “high” category, if the average of any daily mosquito trap count is more than 1,000 mosquitoes or if any individual trap count reaches the high bar of more than 2,000 mosquitoes.
Winnipeg began its fogging program last week with efforts focused on parks and open spaces in response to rise in mosquito numbers in the provincial capital.
If it fogs, Brandon like Winnipeg uses a product called DeltaGard 20EW and not malathion.
Brandon residents are able to annually register for buffer zones, which exclude an area of 90m surrounding their property from being part of any seasonal fogging.
For those looking to be proactive, Lane recommends addressing areas of standing water on one’s property including in eaves troughs and other common collection points. For those wishing to address mosquito population on their own property, providers such as Poulin’s offer control services as well as selling an assortment of recommended DIY product.
More on the City of Brandon’s Mosquito Abatement Program can be learned at: