The number of mosquitoes in Edmonton has dropped significantly so far this summer while the aphid populations are thriving, says the city's biological expert.
Mike Jenkins, a biological sciences technician for the City of Edmonton, says the overall population levels of mosquitoes in the city have dropped due to mostly hot and dry weather this summer.
The city monitors mosquito population levels every year. Jenkins says this time last year there was an average of 800 mosquitoes found per trap. This year, that figure is down to 75.
“It’s about less than a 10th of the mosquitoes we had last year,” Jenkins said. “That’s a pretty big drop.”
Jenkins says mosquitoes lay eggs on the edge of moist areas such as ponds and hatch after the water levels rise up and cover the eggs.
However, the heavy rain in recent days could see a return of mosquitoes in the city. Jenkins says mosquito eggs can sit by bodies of water waiting for levels to rise for as long as 10 years.
“With everything in Alberta, it depends entirely on the weather,” Jenkins said. “If we get lots of rainfall coming in and recharging those environments and causing hatching, we could definitely get lots of mosquitoes coming later in the seasons.”
Aphids thriving in Edmonton
Unlike mosquitoes, which thrive in cool and wet conditions, aphids can survive in hot and dry weather.
Jenkins says aphids, the tiny little garden pests, have had a successful year thanks to accommodating conditions and rapid reproduction process called parthenogenesis.
“The female is actually giving live birth to a clone of herself and those clone nymphs are actually already pregnant with their own grandchildren when she gives birth to them,” he said. "They can build up huge populations incredibly quickly.”
Once aphids get into an area, if there are no predators to keep them in check, they can reproduce very quickly.
Ants also help protect the tiny pests.
“Ants will actually ranch aphids and actually collect their honeydew, which is essentially aphid pee,” Jenkins said. "They use it as a food source."