If you’ve seen a bite on your arm or heard an annoying buzz in your ear, prepare for the worst. Aside from flooding several streets and houses, the record rainfall seen by the city of Winnipeg last week has provided prime conditions for the blood-sucking, disease-carrying mosquitoes. According to authorities, the city received as much rain over the weekend as what it receive in normal conditions for the entire month of June, significantly increasing the amount of standing floodwater and, with it, the rejuvenated mosquito swarms.
In a recent interview for CBC News, Ken Nawolsky, superintendent of the Insect Control Branch in Winnipeg, explained that the recent surge in their population is accounted for by the fact that, “The eggs that have laid dormant for the last three to five years have hatched in the water because of the significant amount of rainfall.” Although pest control professionals are moving fast to remove colonies of mosquitoes from pools of standing water across the city, homeowners can help speed up the process by removing every body of pooling water on their property.
The pest control treatments used so far by city authorities include larvicides and residual treatments, but they may be forced to resort to fogging as more rain and probably some storms are expected to move into western Manitoba and northwestern Ontario over the next couple of days. The rain is expected to taper off starting Monday.
Surely you’ve wondered by now how do mosquitoes manage to survive in the rain, considering their puny, fragile bodies are 50 times smaller than a single raindrop? Since other winged critters must spend twice as much energy to navigate through falling rain, as in the case of bats, precipitation must cause a great deal of harm to insects no bigger than the raindrops themselves. Or is it that they can somehow sense rain coming and hide someplace safe, waiting for it to be over?
The answer comes from researchers at Georgia Tech and Harvard University, who found that the little insects are so light, that falling water drops simply brush them aside, without causing significant impact. In the lab, scientists were able to study their mechanism for survival: “A mosquito’s strong exoskeleton and low mass renders it impervious to falling drops. The mosquito’s low mass causes raindrops to lose little momentum upon impact and so impart correspondingly low forces to the mosquitoes. Our findings demonstrate that small fliers are robust to in-flight perturbations.”
Scientists have compared their mechanism with boxing with a balloon: since no resistance is opposed, it’s almost impossible to pop the balloon. In 1 in 4 times, a raindrop falls directly between a mosquito’s fragile wings, and for a brief period, the insect is absorbed into the water. However, it manages to pull away seconds before the drop hits the ground and save itself. So, they manage to survive falling rain by simply minding their own business and doing nothing about it.
If we know one thing about mosquitoes, is that everybody hates them with a passion. Not being able to stand outside the house for more than two minutes without having to swat away at the always-hungry tiny vampires sends Canadians on a desperate search for effective remedies. And it’s not just because of the itchy welts and discomfort, but also the many health risks they pose, from malaria and dengue (with more than 300 million victims worldwide) to the recently-discovered chikungunya virus, which causes fever, headaches, rashes, and joint pain and doesn’t have a cure yet.
Since humidity enables mosquitoes to breed, the first line of defense should be removing all pooling and standing water from your property – pools of water are the number breeding one site where disease-carrying mosquitoes prefer to breed and live. If you have a lake or pond on your property, consider introducing minnows to feed on the mosquito larvae or apply larvicide to the water body to kill the eggs. For those with pools, consider covering them when not in use or treating the water with chlorine and other such chemical additives. Other places that might hold water for mosquitoes to breed in include discarded tires, gutters, buckets, ditches, storm drains, birdbaths, plant saucers, etc.
Using mosquito repellent is, perhaps, the solution at hand for most Canadians who plan on going camping or spending more time in the outdoors this summer. They can choose between DEET repellents (N,N-diethyl-m-toluamide), whose effectiveness lasts for several hours, but which are somewhat controversial because they’re said to cause skin reactions and even cancer, and picardin-based repellents, which must be applied regularly to keep critters at bay. DEET-free repellents have also started to emerge as an effective defense against insects.
But there’s also a completely natural – and quite effective – way to repel mosquitoes from your home and garden during the warm season: growing plants. Citronella, horsemint, basil, marigolds, ageratum, lavender, or catnip are some of the most effective mosquito-repelling plants (most of them are also used in repellent formulas) you can grow by yourself with little effort. Not only will their natural-occurring fragrances annoy and discourage mosquitoes from trespassing on your property, but they will also introduce wonderful scents throughout your home and yard this summer. Make sure to place pots in areas where you spend most time, such as near entryways or by seating areas.
If all the above fails and you are still under the attack of hungry mosquitoes, it’s time to let the pros step in. Using safe, non-toxic methods designed to reduce mosquito populations throughout your property and prevent future infestations, pest control professionals may be your best bet to get away unbitten this summer.
Daniel Mackie, co-owner of Greenleaf Pest Control, is a Toronto pest control expert well-known as an industry go-to guy, an innovator of safe, effective pest control solutions, and is a regular guest on HGTV. Mackie, along with business partner Sandy Costa, were the first pest control professionals in Canada to use detection dogs and thermal remediation for the successful eradication of bed bugs. In his free time, he is an avid gardener.