This summer, some prairie cities in Manitoba, Saskatchewan, and Alberta faced a surge in mosquito populations, leading to a shortage of bug spray in stores due to high demand. Data from the City of Edmonton revealed a significant increase in mosquito numbers in July compared to the previous year. Although not record-breaking, the spike was notable, according to Peter Daly, a biological sciences technologist in Edmonton.
Similarly, Saskatoon and Winnipeg also reported higher mosquito numbers in July compared to the previous year. Experts attribute the mosquito boom in southern Ontario to the record rainfall experienced this summer, particularly favoring the Ochlerotatus trivittatus species. Fiona Hunter, a professor at Brock University, highlighted that the species thrives in flooded areas, which the excessive rain in southern Ontario provided this year.
The persistent biting nature of the Ochlerotatus trivittatus species has increased human-mosquito encounters, contributing to the perception of a worse mosquito season. Moreover, the heavy rainfall in the Greater Toronto Area and other parts of southern Ontario likely triggered the hatching of dormant mosquito eggs, further exacerbating the situation.
As temperatures drop, mosquito populations are expected to decrease. The cold weather negatively impacts mosquitoes, leading to their disappearance. Recent cold snaps in Alberta resulted in a decline in mosquito populations. However, a potential resurgence may occur if temperatures rise again. Despite this, the mosquito populations in central Canada are not anticipated to reach the levels seen in other regions.